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Weather History

October 24 to October 30: This week in Denver weather history

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This Week in Denver Weather History

This year Denver is still waiting for its first snow and we have already passed the average date we see it (October 19).  That however isn’t always the case and October can bring monster snowstorms as we see in our look back at this week in Denver weather history.

From the National Weather Service:

23-24

In 1887…the first measurable snowfall of the season totaled 3.1 inches.  North winds to 20 mph were recorded on the 23rd.  This was the only measurable snow of the month.

In 1932…post-frontal snowfall from the late evening of the 23rd continued through the late afternoon of the 24th and totaled 6.2 inches.  Southeast winds were sustained to 25 mph with gusts to 26 mph on the 23rd.  Temperatures cooled from a high of 68 degrees on the 23rd to a low of 25 degrees on the 24th…the coldest reading of the month that year.  Many trees that had not shed their leaves became heavily laden by the wet snow.  Many branches were broken… And a few trees toppled under the weight of the snow.  The landscape became one of rare beauty.

24

In 1956…southwest winds gusted to 56 mph and produced some blowing dust at Stapleton Airport.  A cold front produced a thunderstorm with 1/8 inch hail.  Rain later changed to snow.  Precipitation totaled only 0.11 inch and snowfall only 0.3 inch.

In 1973…strong winds raked the eastern foothills…causing damage in Boulder and Jefferson counties.  The heaviest damage occurred in the Boulder area where 20 to 25 mobile homes were hit…some power and telephone lines were blown down…and a store was damaged.  A wind gust to 76 mph was recorded in Boulder at the National Bureau of Standards. Northwest winds gusted to 46 mph at Stapleton International Airport.

24-25

In 1921…rainfall totaled 0.35 inch overnight behind an apparent cold front.  North winds were sustained to 40 mph with gusts to 46 mph on the 25th.  Temperatures plunged from a high of 73 degrees on the 24th to a low of 39 degrees on the 25th.

In 1923…rain overnight changed to snow during the morning. The heavy snowfall accumulated to 12.0 inches before ending on the morning of the 25th.  Post-frontal north winds were sustained to 22 mph with gusts to 23 mph on the 24th.

In 1997…one of the worst and deadliest blizzards of the decade developed over eastern Colorado as deep east to northeast flow associated with a vigorous upper level low pressure system over the Four Corners…combined with a strong arctic air mass over the central Great Plains. Snowfall totals across metro Denver ranged from 14 to 31 inches.  The heaviest snowfall occurred in the foothills west and southwest of Denver where 2 to 4 feet of snow were measured.  Sustained winds to 40 mph with gusts as high as 60 mph produced zero visibilities and extremely cold wind chill temperatures from 25 below to 40 below zero.  Winds whipped the snow into drifts 4 to 10 feet deep.  Several major and interstate highways were closed as travel became impossible.  Red Cross shelters were set up for hundreds of travelers who became stranded when they had to abandon their vehicles.  Four people died in northeastern Colorado as a result of the blizzard.  None of the deaths were in metro Denver.  At Denver International Airport…4 thousand travelers were stranded when the airport was forced to shut down.  At least 120 cars were abandoned along Pena Blvd….the only arterial leading into and out of DIA.  The blizzard cost air carriers at least 20 million dollars.  Thousands of cattle died in the storm over northeastern Colorado…resulting in losses totaling 1.5 million dollars.  Some of the more impressive snowfall totals included:  51 inches at Coal Creek Canyon; 48 inches at Silver Spruce Ranch…near Ward; 42 inches at Intercanyon…in the foothills southwest of Denver; 37 inches at Sedalia; 35 inches at Aspen Springs and Conifer in the foothills west of Denver; 31 inches at Eldorado Springs… Southeast Aurora…and Englewood; and 30 inches on Table Mesa in Boulder.  Snowfall totaled 21.9 inches at the site of the former Stapleton International Airport…setting a new 24-hour snowfall record of 19.1 inches for the month. Snowfall totaled only 14 inches at Denver International Airport where north winds gusted to 39 mph on the 24th. High temperature of only 21 degrees on the 25th equaled the record low maximum for the date first set in 1873. Low temperature of only 3 degrees on the 26th set a new record minimum for the date.

25

In 1925…a vigorous cold front produced north winds sustained to 42 mph with gusts to 52 mph.  Post-frontal snowfall was only 0.4 inch during the late afternoon and early evening.

In 1959…northwest winds gusted to 55 mph at Stapleton Airport.

In 1997…the high temperature warmed to only 21 degrees…the record low maximum for the month.  The same temperature also occurred on October 30…1991.

25-26

In 1996…4 to 6 inches of snow fell in the foothills west of Denver.  Only 1.5 inches of snowfall were measured at the site of the former Stapleton International Airport on the 26th.  This was the only measurable snow of the month at the site.  The snowfall produced icy and snowpacked highways…which resulted in a 50-to 60-car pileup on I-25 south of metro Denver.  West winds gusted to 33 mph at Denver International Airport.

In 2006…a winter storm brought heavy snowfall to metro Denver and the eastern foothills.  Total snowfall ranged from 12 to 22 inches over the higher terrain and 6 to 12 inches across metro Denver.  Northerly winds at sustained speeds of 20 to 30 mph with gusts as high as 47 mph at Denver International Airport whipped the snow into drifts 3 to 4 feet deep.  Many tree limbs snapped under the weight of the heavy…wet snow which also downed power lines… Leaving thousands of residents without power.  Storm total snowfall included:  25 inches near Aspen Springs…conifer… And Evergreen; 23.5 inches near Rollinsville; 23 inches in Idaho Springs; 22.5 inches near Blackhawk; 21.5 inches near Bailey; 19 inches near Bergen Park; 18 inches near Aspen Springs…Genesee…and Jamestown; 17 inches southwest of Boulder; 16 inches in Evergreen; and 15 inches near Georgetown and Perry Park.  Snowfall totaled 5.3 inches in the Denver Stapleton area.  At Denver International Airport…rain…including a thunderstorm…changed to snow on the evening of the 25th after a high temperature of 70 degrees.

In 2010…a storm system brought heavy snow to the mountains west of Denver. Storm totals included: 24 inches at the Eisenhower Tunnel…18 inches at Loveland Ski Area; with 16 inches at Arapahoe Basin.

25-27

In 1897…a major storm dumped 13.5 inches of snowfall over downtown Denver.  Rain changed to snow during the evening of the 25th and continued through mid-morning of the 27th. Most of the snow…12.0 inches…fell on the 26th when north winds were sustained to 36 mph and gusts were as high as 46 mph.  Temperatures during the storm were in the 20’s and lower 30’s.  Precipitation (rain and melted snow) totaled 1.21 inches.

26

In 1995…winds gusting from 100 to near 110 mph pounded the foothills northwest of Denver.  At Nederland winds gusted to 100 mph and to 70 mph in Coal Creek Canyon.  Atop Squaw Mountain west of Denver wind gusts to 108 mph were recorded.  The strong winds downed some trees and caused power outages.  West-northwest winds gusted to 47 mph at Denver International Airport.

In 2010…very strong winds during the day knocked down power lines in parts of Boulder. The downed electrical lines sparked a small brush fire near Columbine Elementary School. Strong wind gusts also damaged the tennis bubble at the Millennium Harvest House. In Northglenn. a tree was knocked down and caused minor damage to a mini-van parked nearby. Peak wind gusts included: 70 mph at Berthoud…67 mph at Rocky Mountain Metropolitan Airport in Broomfield… 63 mph at the Rocky Flats National Wind Technology Center and 59 mph at the NCAR Mesa Laboratory…3 miles southwest of Boulder. West winds gusted to 43 mph at Denver International Airport.

In 2011…a powerful early season storm brought heavy snow to the Front Range and adjacent plains. The heavy…wet snow caused extensive downed large branches and in some cases…entire trees. Massive power outages occurred from Fort Collins and Greeley south to Denver and the surrounding metro area. Most of the trees still had their leaves…which helped to catch snow and down trees under the weight of the moisture laden snow. Nearly two hundred thousand utility customers along the Front Range were without heat and electricity for several hours. The Red Cross opened four temporary shelters overnight until the power could be restored. The outages also forced the closure of the Boulder Criminal Justice Center the following day. The fallen trees and branches also caused extensive property damage to roofs and automobiles. In the Front Range mountains and foothills…storm totals included 19.8 inches…3 miles west of Jamestown; 18 inches…5 miles west of Copper; 13 inches…3 miles north of Blackhawk and 3 miles south of Evergreen…4 miles east-northeast of Nederland and Lake Eldora; 12 inches at Berthoud SNOTEL. Across the Urban Corridor storm totals included: 11.5 inches in Boulder; 9.5 inches at the National Weather Service in Boulder; 9 inches…1 mile southwest of Westminster; 8.5 inches in Broomfield… Denver International Airport…Frederick and Louisville; 8 inches in Aurora…7 inches in Watkins; with 6 inches in Arvada.

Continue reading October 24 to October 30: This week in Denver weather history →

Weather History

October 17 to October 23: This week in Denver weather history

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This Week in Denver Weather History

This year Denver is still waiting for its first snowfall but that certainly has not been the case throughout history.  Many times in our past we have seen not only snow around this time of October but heavy snow as well, oftentimes damaging in nature.

15-17

In 1989…an autumn snowstorm hit metro Denver with 2 to 6 inches of snow.  Snowfall totaled 4.4 inches at Stapleton International Airport where the maximum snow depth on the ground was only 3 inches due to melting and north winds gusted to 25 mph on the 15th.  The heavy wet snow caused leafy branches to sag onto power lines…resulting in a number of power outages.  Five thousand homes were blacked out in Boulder on the 16th.  Up to a foot of snow fell in the higher foothills with 19 inches recorded at Echo Lake.

16-17

In 1990…strong downslope winds raked the eastern foothills. Wind gusts from 60 to 75 mph were common.  Strong winds in metro Denver resulted in wave damage to a dock used to moor several private sail boats at Cheery Creek Reservoir. Damage was confined to the dock and two anchor cables. A northwest wind gust to 43 mph was recorded at Stapleton International Airport.

17

In 1878…strong winds reached sustained speeds of 48 mph.

In 1988…a wind gust to 62 mph was recorded in central Boulder.  The strong winds caused a few brief power outages.  An old smoldering brush fire in the foothills west of Boulder was re-ignited by the wind gusts.

In 1994…winds gusted to 85 mph atop Squaw Mountain…5 miles south of Idaho Springs.

In 2006…a potent storm system brought heavy snowfall to the mountains and eastern foothills.  Snowfall totals in the foothills included:  14 inches at Blackhawk…13.5 inches near Idaho Springs…13 inches at cabin creek…12.5 inches at Aspen Springs and Echo Lake…11.5 inches at Georgetown and Rollinsville…10.5 inches near Jamestown…and 10 inches at grant and Lake Eldora.  Lesser snow amounts…from 4 to 9 inches…were recorded elsewhere in the foothills.  Snowfall totaled only 3.5 inches in the Denver Stapleton area.  At Denver International Airport…north winds gusted to 31 mph.

In 2012…A brief but powerful windstorm associated with a fast moving cold front across the Urban Corridor and adjacent plains during in the evening. Peak wind gusts ranging from 58 to 71 mph downed trees and power lines which damaged homes and vehicles. Several temporary structures were also damaged. Approximately fifty thousand were left without power in the Denver…Fort Collins and Greeley areas. Some schools were closed the following day until power could be restored. Around the Denver area…peak wind gusts included: 69 mph in Golden…64 mph at Littleton… 62 mph at Buckley AFB and in Denver…near the intersection of Walnut St. and Interstate 25…and Longmont; 59 mph at Centennial Airport…58 mph at Denver City Park…Highlands Ranch. At Denver International Airport…a peak wind gust to 35 mph was observed from the northwest.

17-19

In 1908…a moist…heavy…wet snowfall totaled 13.0 inches in downtown Denver over the 3 days.  Rain from early morning on the 17th changed to snow by late afternoon and continued through the late morning of the 19th.  Due to temperatures in the 30’s and melting…the most snow on the ground was only 5.0 inches at 6:00 pm on the 18th.  Northwest to northeast winds were sustained between 12 and 20 mph during the storm.  Precipitation totaled 1.82 inches.

Continue reading October 17 to October 23: This week in Denver weather history →

Weather History

October 10 to October 16: This week in Denver weather history

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This Week in Denver Weather History

The farther we get into fall the more we start seeing significant snow events in our look back at the week in history.  None of these is more famous than the “Bronco Blizzard” of 1984 that saw the Mile High City buried under nearly a foot of snow – on live television.

From the National Weather Service:

9-10

In 2005…a major winter storm brought heavy…wet snowfall to the Front Range mountains…eastern foothills…portions of metro Denver…and the Palmer Divide.  Snow accumulations ranged from 8 to 26 inches with drifts from 3 to 4 feet in places.  The heaviest snow occurred to the east and southeast of the city…closing most major highways in that area…including I-70 from Denver to Limon.  The Red Cross opened four shelters for people who were stranded along I-70 in eastern Colorado.  Since many trees had not yet shed their leaves…the storm caused significant tree damage.  One woman in Denver was killed when a tree branch… 8 to 10 inches in diameter…snapped under the weight of the heavy…wet snow and struck her as she was shoveling her driveway.  Xcel Energy reported power outages to about 35 thousand customers.  Several incoming flights were delayed at Denver International Airport.  Snow totals included:  16 inches in the foothills near Boulder…12 inches at Genesee and near Golden…22 inches near Watkins…19 inches near Bennett…17 inches southeast of Aurora…14 inches near Parker…13 inches near Castle Rock…12 inches in centennial… 11 inches in Parker…and 10 inches at Denver International Airport and in Littleton.  While many areas of metro Denver received heavy snow…others experienced almost entirely rain. This included west and northwest metro Denver…Boulder…and Longmont.  Rainfall amounts were significant as storm totals ranged between 1.50 and 2.50 inches.  The steady rainfall triggered 3 rockslides in foothills canyons.  Two of the slides occurred on State Highway 119 in Boulder canyon and the longest slide…7 feet in length…on State Highway 74 in Bear Creek Canyon at Idledale.  North winds were sustained to around 23 mph with gusts to 31 mph at Denver International Airport on the 9th.  The high temperature of only 34 degrees on the 10th was a record low maximum for the date.  The low temperature on both days was 32 degrees.

10

In 1901…an evening thunderstorm produced east winds to 43 mph with gusts to 48 mph.

In 1949…strong winds believed to be the worst in Boulder’s history at the time caused over 100 thousand dollars damage in the city.  Peak winds were estimated to 85 mph at Valmont…just east of Boulder.  High winds also occurred over most of metro Denver and caused damage to trees…window glass…and utility lines.  The damage was most pronounced over the northwest metro area…including north Denver and Lakewood.  Falling tree branches caused damage to parked autos and houses.  Wind gusts to 70 mph were recorded at Stapleton Airport.

In 1964…lightning struck and killed a 13-year-old boy…while he was riding his bicycle along a tree-lined residential street in south Denver.  Apparent microburst winds gusted to 54 mph at Stapleton International Airport.

10-11

in 1986…the first significant snowstorm of the season produced 2 to 5 inches of snow over metro Denver with 5 to 10 inches in the foothills west of Denver.  Wondervu recorded the most snow from the storm…13 inches.  The heavy wet snow caused numerous power outages.  The storm was accompanied by strong north winds with gusts to 41 mph recorded on the 10th.  The first snowfall of the season totaled 3.1 inches at Stapleton International Airport with only one inch on the ground due to melting.  The strong cold front accompanying the storm cooled the temperature from a high of 73 degrees on the 10th to a high of only 33 degrees on the 11th…which was a record low maximum for the date.

10-12

In 1969…the second heavy snowstorm in less than a week dumped nearly a foot of snow across metro Denver and plunged the area into extremely cold temperatures for so early in the season.  Snowfall totaled 11.0 inches at Stapleton International Airport.  North winds gusting to 26 mph produced drifts up to 2 feet deep.  Temperatures dipped from a high of 52 degrees on the 10th to a record low for the date of 10 degrees on the 12th.  There was additional damage to trees and power and telephone lines from heavy snow accumulations and icing.  Travel was restricted or blocked by drifting snow in both the mountains and on the plains east of Denver.

11

In 1997…damaging winds ahead of an approaching storm system developed in the foothills and spread across metro Denver. Winds gusted to 88 mph at conifer…71 mph at the National Center for Atmospheric Research on the mesa in Boulder… And 53 mph at Denver International Airport.  Several trees and street signs were blown down with scattered power outages reported throughout metro Denver. In Arvada…a car window was blown out by a strong wind gust.

In 2013…high winds occurred in and near the Front Range Foothills. Peak gusts included: 85 mph at Rooney Road… 84 mph…2 miles south of Marshall; 82 mph at Rocky Flats National Wind Technology Center and Wondervu; 79 mph at the Mesa Lab at NCAR and 75 mph…3 miles south-southwest of Boulder; 73 mph in Superior and 68 mph in Golden. The wind downed trees and power lines. As a result…scattered electrical outages affected 20000 Xcel Energy customers through the morning hours. The main outages affected the cities of Boulder…Golden and Lakewood. Smaller outages were reported in areas of Gold Hill…Ward…Westminster and Wheat Ridge.

11-12

In 1901…an apparent cold front produced northeast winds sustained to 42 mph with gusts to 48 mph on the 11th. General rain changed to snow overnight and totaled 2.0 inches.  This was the first snowfall of the season. Total precipitation was 0.32 inch.

11-13

In 1892…apparent post-frontal rainfall totaled 3.33 inches in downtown Denver over the 3 days.  A trace of snow on the 12th melted as it fell.  Rainfall of 2.58 inches on the 12th into the 13th was the greatest 24-hour precipitation ever recorded during the month of October.  Northwest winds were sustained to 48 mph with gusts as high as 55 mph on the 12th.

12

In 1873…smoke from several very large forest fires was sighted along the mountains.

In 1923…post-frontal rain changed to snow and totaled 4.0 inches.  North winds were sustained to 14 mph.

In 1978…northeast winds gusting to 35 mph with a strong cold front briefly reduced visibility to 2 miles in blowing dust at Stapleton International Airport.

12-13

In 2001…overnight peak wind gusts to 82 mph and 70 mph were measured atop Niwot Ridge and Squaw Mountain… Respectively.

12-14

In 1969…record breaking extremely cold temperatures for so early in the season occurred.  The high temperature of 26 degrees on the 13th was two degrees lower than the previous record minimum temperature of 28 degrees for the date set in 1885.  The high temperature of 24 degrees on the 12th exceeded the record low temperature (22 degrees set in 1885) for the date by only 2 degrees.

In addition… 3 new record low temperatures for the dates were set.  The low temperature dipped to 10 degrees on the 12th breaking the old record (22 degrees in 1885) by 12 degrees.  On the 13th the mercury plunged to a low of 3 degrees breaking the old record (28 degrees in 1885) by 25 degrees.  On the 14th the temperature reached a minimum of 4 degrees breaking the old record (25 degrees in 1966) by 21 degrees.

13

In 1990…strong downslope winds stirred up clouds of dust and gravel…rattled windows…and stripped autumn-colored leaves from trees in Boulder.  A wind gust to 78 mph was clocked in southwest Boulder…while a 96 mph gust was recorded in northwest Boulder.  West winds gusted to only 36 mph at Stapleton International Airport.

13-14

In 1910…light smoke from nearby forest fires drifted over the city.

In 1966…the first measurable snow of the season caused widespread damage to trees and shrubs.  The heavy wet snow totaled 6.9 inches at Stapleton International Airport where north-northwest winds sustained at 20 to 25 mph and gusting to 45 mph caused much blowing and drifting snow. South and east of Denver…up to a foot of snow fell.  Heavy wet snow accumulations followed by freezing temperatures and strong winds resulted in extensive damage to trees…cars… And utility lines by falling limbs.  A woman was killed by a falling snow laden tree limb in Denver.  Several other people received minor injuries from falling tree limbs.

In 1987…rain drenched metro Denver.  The South Platte canyon area southwest of Denver received the most with 1.11 inches at Kassler and 1.49 inches upstream at Strontia Springs.  At Stapleton International Airport…0.62 inch of rain was measured…northwest winds gusted to 29 mph…and thunder was heard.

In 2007…a new 24-hour record of 2.65 inches of precipitation was set at Denver International Airport for the month of October; breaking the previous record of 2.58 inches set in 1892.

13-16

In 1873…smoke from several large forest fires in the mountains made the air very hazy in the city.

14

In 1952…the first measurable snowfall of the season left 1.2 inches of snow at Stapleton Airport.  North winds gusted to 38 mph.

In 1974…rain changed to snow early in the day…but snowfall totaled only 1.0 inch at Stapleton International Airport where northeast winds gusted to 20 mph.

15

In 1871…a terrible wind occurred during a snow storm in the foothills above Boulder.  Damage was minor.

In 1878…high winds reached sustained speeds of 60 mph at times.

In 1911…post-frontal northwest winds were sustained to 41 mph with gusts to 43 mph.

In 1948…strong winds struck the Boulder area.  Winds averaged 50 mph at Valmont just east of Boulder.  Wind gusts in excess of 60 mph were recorded at the Boulder airport.  Wind gusts to 40 mph briefly reduced the visibility to 1 1/2 miles in blowing dust at Stapleton Airport.

In 1980…a rare October tornado touched down in Boulder… Damaging a vocational training building and throwing three nearby cars together damaging them extensively.  A mile and half away several camper vehicles were thrown 200 feet. The storm also produced 1 inch diameter hail in the Boulder area.

15-16

In 1928…a thunderstorm produced hail shortly after midnight on the 15th.  Rain changed to snow by evening.  Through the afternoon of the 16th…the heavy snowfall totaled 7.3 inches in the city.  North winds were sustained to 23 mph on the 15th.

In 1984…the heaviest October snowstorm in several years hit eastern Colorado with a vengeance.  The storm was known as the “bronco blizzard” since it occurred during a nationally televised Monday Night Football game in Denver.  One to two feet of snow fell near the foothills in west metro Denver with 2 to 3 feet in the foothills.  Wind gusts up to 55 mph whipped the snow into drifts as high as 4 feet. The storm closed schools…roads…and airports.  I-70 was closed both east and west of Denver.  I-25 was closed south to Colorado Springs.  Flights were delayed for several hours at Stapleton International Airport.  Power outages were widespread.  Snowfall totaled 9.2 inches at Stapleton International Airport where north winds gusting as high as 40 mph caused frequent surface visibilities of 1/4 to 1/2 mile in moderate to heavy snow and blowing snow overnight.  The high temperature of only 35 degrees on the 15th was a record low maximum for the date.

15-17

In 1989…an autumn snowstorm hit metro Denver with 2 to 6 inches of snow.  Snowfall totaled 4.4 inches at Stapleton International Airport where the maximum snow depth on the ground was only 3 inches due to melting and north winds gusted to 25 mph on the 15th.  The heavy wet snow caused leafy branches to sag onto power lines…resulting in a number of power outages.  Five thousand homes were blacked out in Boulder on the 16th.  Up to a foot of snow fell in the higher foothills with 19 inches recorded at Echo Lake.

Continue reading October 10 to October 16: This week in Denver weather history →

Weather History

October 3 to October 9: This week in Denver weather history

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This Week in Denver Weather History

The first half of October historically is quiet for the most part but there have been years with plenty of excitement.  We have seen damaging tornadoes and winds and of course significant snowstorms.

From the National Weather Service:

3

In 1875…very dense haze hid the mountains from view as observed from the city.

In 1933…rainfall of just 0.01 inch was the only precipitation of the month.  This was the second driest October on record.

In 1954…the low temperature cooled to only 60 degrees…the all-time record high minimum for the month October.

3-4

In 1969…the first snowfall of the season totaled 16.0 inches at Stapleton International Airport.  There was a thunder snow shower on the evening of the 3rd…but otherwise little wind with the storm.  The greatest snow depth on the ground was 8 inches due to melting.  Heavy wet snow accumulated on trees…which were still in full leaf…and caused widespread damage from broken limbs and downed utility lines.

3-5

In 1984…the remnants of Pacific Hurricane Polo produced heavy rain over northeastern Colorado.  Most locations received between 1.00 to 2.50 inches of rain…but 3.45 inches fell in Littleton.  Rainfall totaled 1.73 inches at Stapleton International Airport…where north winds gusted to 24 mph.

4

In 1912…sustained south winds to 55 mph with gusts to 60 mph raised the temperature to a high of 83 degrees… The warmest temperature of the month that year.

In 1924…west winds were sustained to 46 mph with gusts to 50 mph in the city.  The apparent Bora winds cooled the temperature to a high of 57 degrees from a high of 70 degrees on the 3rd.

In 2004…several small tornadoes touched down near Brighton… Barr Lake…and Hudson in Adams and southern Weld counties. Most of these caused no damage.  However…a small tornado 5 miles southeast of Brighton caused extensive damage to a recreational vehicle and severely damaged a barn.  The barn was torn from its foundation…and the roof was thrown 100 feet.  Four llamas in the barn were injured when it collapsed.

4-5

In 1997…unusually warm weather resulted in two temperature records.  High temperature of 87 degrees on the 4th exceeded the old record set in 1922 by one degree.  High temperature of 86 degrees on the 5th equaled the record set in 1990 and previous years.

5

In 1962…unusually severe thunderstorms for this late in the season affected areas from Boulder northward.  Hail up to golf ball size and strong gusty winds did much damage to roofs…windows…and signs in Boulder.  Heavy rainfall caused local flooding.

In 1994…lightning caused a power outage to over 2400 homes for a few hours in and around Nederland in the foothills southwest of Boulder.  Very strong winds accompanied the thunderstorm.  Thunderstorm winds gusted to 60 mph and hail to 1/2 inch diameter fell in Lafayette.  Strong microburst winds gusting to 69 mph near Strasburg caused an oil rig to topple onto two vehicles…injuring one person.  The strong winds in the area also downed a few power poles… But caused power outages to only a few homes.

In 1995…strong winds spread from the foothills onto the plains.  Wind gusts to 77 mph were reported atop Squaw Mountain west of Denver.  On the plains…winds gusted to 60 mph at Kennesburg and to 62 mph near Strasburg. North winds gusted to 41 mph at Denver International Airport.

Continue reading October 3 to October 9: This week in Denver weather history →

Weather History

September 26 to October 2: This week in Denver weather history

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This Week in Denver Weather History

Denver has been graced with an unusually mild September this year.  That however is not always the case and in fact the weather can be downright winterish as we see in our look back at this week in Denver weather history.

25-26

In 1908…apparent post-frontal rain changed to snow overnight and totaled 6.5 inches in downtown Denver.  This was the first snow of the season.  Precipitation totaled 0.76 inch. North winds were sustained to 39 mph on the 25th.

25-27

In 1996…an early season snowstorm brought heavy snow to the Front Range eastern foothills.  Snowfall totals included:  8 to 12 inches around conifer…7 inches on Floyd Hill…and 6 inches at both Bailey and Chief Hosa. Snowfall totaled only 4.7 inches at the site of the former Stapleton International Airport.  This was the first measurable snow of the season.  After the passage of a strong cold front…north winds gusted to 38 mph at Denver International Airport on the 25th.

26

In 1907…a late afternoon thunderstorm produced hail…0.23 inch of precipitation…and north winds sustained to 24 mph.

In 1927…snowfall of 1.7 inches…mixed at times with sleet… Was the first measurable snowfall of the season.

In 2012…a man was seriously injured when he was struck by lightning outside the Hebrew Educational Alliance as he and his family were getting in their car. The victim stopped breathing but was saved when his wife performed cardiopulmonary resuscitation on him immediately following the lightning strike. He suffered burns to 15 percent of his body which included his legs…chest… abdomen and neck. Lightning also caused 48 outages in Denver which affected 6582 Xcel Energy customers.

26-28

In 1936…the heaviest snowfall ever recorded in September and the heaviest snowfall ever recorded so early in the season dumped a total of 16.5 inches of snow on downtown Denver and 21.3 inches at Denver municipal airport.  The 15.0 inches of snow measured from 6:00 pm on the 27th to 6:00 pm on the 28th is the greatest 24 hour snowfall ever recorded in September.  This was the first snow of the season.  The snow was intermittent through the 26th…but continuous from early afternoon on the 27th to around midnight on the 28th…except for a period of rain during the afternoon of the 28th which contributed to a loss of depth on the ground.  The greatest snow depth on the ground downtown was 13 inches with 8 inches at Denver municipal airport.  There were no high winds with the storm and traffic was interrupted for only a short period.  The storm produced property damage estimated at 7 million dollars.  With trees and shrubs in full foliage…the leaves caught and held the heavy water-laden snow…until the branches snapped from the weight.  More than 3000 workmen were called to remove the debris and snow from the city.  The city firemen who were off duty…as well as all the reserves… Were asked to report to their stations.  All schools in the city remained open…but attendance was only 50 percent of normal.  Grade school students were sent home at noon on the 28th.  The early storm caught stockmen with many cattle still in higher ranges.  Warm weather followed the snow…which had all melted by the end of the month…except for a few inches in sheltered places.

27

In 1877…smoke from heavy forest fires in the mountains spread over the city on upper wind currents.

In 1935…the first snow of the season was 2.8 inches in downtown Denver.  The low temperature dipped to 31 degrees for the first freeze of the season.

27-28

In 1984…heavy snow fell over the plains and foothills. Snowfall amounts ranged from 2 to 5 inches on the plains with up to a foot at higher elevations in the foothills. The main problem caused by the storm was thousands of power outages caused by snow-laden tree limbs snapping and falling onto power lines.  Over 15 thousand homes lost power in metro Denver.  Some cars were damaged by falling trees and limbs.  The snow also caused some flight delays at Stapleton International Airport where 5.1 inches of snow fell and northeast winds gusted to 29 mph.  Maximum snow depth on the ground was 3 inches due to melting.  The high temperature of only 34 degrees on the 28th was a record low maximum for the date and equaled the all-time record for the month at that time.

28

In 1877…heavy dense smoke from mountain forest fires spread over the city.  The smoke was so dense that it obscured the sun at times.

In 1921…post-frontal northeast winds were sustained to 44 mph.

In 1953…a pacific cold front produced a west wind gust to 59 mph at Stapleton Airport where the visibility was briefly reduced to 3/4 miles in blowing dust.  Strong winds were also widespread over Boulder during the afternoon.

In 1960…strong…gusty winds tore the roof from 6 units of a motel on west Colfax Avenue in Denver.  The roofing sailed over the building and crashed down on a truck…wrecking it. The strong winds were the result of an apparent microburst.

In 1999…snow fell in the foothills west of metro Denver and over the plains.  Snowfall totals included 7 inches at conifer.  At the site of the former Stapleton International Airport…3.1 inches of snow were measured.  This was the first snow of the season.  The heavy wet snow snapped branches from fully leafed trees…downing power lines and causing scattered outages.

In 2004…severe thunderstorms produced hail to 3/4 inch in diameter in Littleton and in Douglas County 14 miles northwest of Castle Rock.

In 2012…a weak tornado (EF-0) tornado touched down near Strasburg. No damage was reported.

Continue reading September 26 to October 2: This week in Denver weather history →

Weather History

September 19 to September 25: This week in Denver weather history

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This Week in Denver Weather History

This time of year many folks would consider “snow” a bad four-letter word but living in the Mile High City we can’t rule it out even with it technically still being summer.  In fact, it was only 15 short years ago that we received a significant snowstorm that brought up to 8 inches of snow in the metro area and caused millions of dollars in damage.

From the National Weather Service:

15-19

In 1906…rain on 5 consecutive days totaled 1.61 inches. A thunderstorm occurred on the 17th.  High temperatures ranged from 48 degrees on the 16th to 65 degrees on the 15th.  Low temperatures were in the lower to mid 40’s.

16-19

In 1971…a record breaking early fall snow storm caused extensive damage to trees and utility lines.  The heavy wet snow occurred with little wind…but caused record breaking cold temperatures for so early in the season.  Snowfall totaled 15.6 inches at Stapleton International Airport with most of the snowfall…12.0 inches…occurring on the 17th.  This was the heaviest first snow of the season. The maximum snow depth on the ground was 13 inches. Record low temperatures were set on three consecutive days: 31 degrees on the 17th…23 degrees on the 18th…and 20 degrees on the 19th…which was also a new all-time record minimum for the month at that time.  Record low maximum temperatures were set on 4 consecutive days:  48 degrees on the 16th…35 degrees on the 17th…40 degrees on the 18th… And 42 degrees on the 19th.

18-19

In 1955…heavy rains caused flash flooding across portions of metro Denver.  Rainfall totaled 1.71 inches at Stapleton Airport.

19

In 1955…hail stones to 2 1/2 inches in diameter were reported north of Denver.  The large stones broke many automobile windshields.

In 1963…hail to 3/4 inch in diameter fell in Westminster.

In 1983…an unusually strong cold front roared through metro Denver during the afternoon hours.  At Stapleton International Airport…the temperature dropped 51 degrees… From a sunny 86 degrees to a snowy 35 degrees…in just 7 hours.  Strong winds and a wall of blowing dust followed the front.  Northeast winds gusting to 36 mph briefly reduced the surface visibility to 1 mile in blowing dust at Stapleton International Airport where only a trace of snow fell later.

In 1996…high winds gusting to 84 mph were measured at Golden Gate Canyon in the foothills west of Denver. West winds gusted to only 25 mph at Denver International Airport.

20

In 1921…an apparent Bora produced northwest winds sustained to 44 mph with gusts to 64 mph.

In 1955…hail stones 1/2 to 3/4 inch in diameter were reported across parts of the city of Denver.

In 1992…weather observers at Buckley Air National Guard base sighted two tornados southeast of the base.  The tornados were short-lived and caused no injuries or damage.

20-21 in 1963…heavy rain and hail caused local flooding in southeast Denver.  Thunderstorm rainfall was only 0.60 inch at Stapleton Airport on the 20th.

In 1983…the cold front on the 19th brought an unusually cold air mass into metro Denver for so early in the season.  The temperature dipped to a daily record minimum of 28 degrees on both days.

In 1995…a vigorous late summer storm brought the season’s first heavy snow to portions of metro Denver.  Millions of trees were damaged and power lines downed as 4 to 8 inches of heavy wet snow settled on fully leafed trees in the Boulder and Denver areas.  Branches snapped and trees split under the weight of heavy snow…downing power lines. Firefighters responded to numerous transformer fires. Around 100 thousand people were left without electricity in Boulder and Denver areas alone.  It took over a week to fully restore power to some areas.  Insurance claims were estimated to be around 6 million dollars to homes in metro Denver and about 500 thousand dollars in damage to automobiles.  It was estimated that about 80 percent of 125 million dollars worth of city owned trees in Denver were damaged.  Snowfall totaled 7.4 inches at the site of the former Stapleton International Airport where the greatest depth of snow on the ground was only 4 inches due to melting.  Temperature records were set on the 21st when the thermometer dipped to a record low reading of 27 degrees and climbed to a high of only 36 degrees… Setting a record low maximum for the date.  North winds gusted to 29 mph at Denver International Airport on the 20th.

Continue reading September 19 to September 25: This week in Denver weather history →

Weather History

September 12 to September 18: This week in Denver weather history

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This Week in Denver Weather History

Normally one doesn’t associate tornadoes with September weather in Denver but they can and do happen as we see in our look back in Denver weather history for the week.  We have a couple of occasions of twisters and of a funnel cloud.  Other severe weather like hail, damaging wind and flooding rains have also occurred.   Oh, and should we mention the dreaded “S” word – snow?

5-13

In 2010…the Fourmile Canyon Wildfire…northwest of Boulder… broke out on the morning of the 5th. It originated from an unattended fire pit at a local residence. The wildfire quickly consumed 5 1/2 square miles or 3500 acres the first day…and forced the evacuation of over three thousand residents. Erratic 45-mph gusts sent the fire in two directions at times. Very dry weather conditions preceded the fire. The combination of strong winds…low relative humidities and dry fuels allowed the wildfire spread rapidly through the steep…heavily forested terrain. The flames were reportedly 20 to 50 feet in length. Towns within the burn area included Salina…Wallstreet and Gold Hill. The dry conditions coupled with gusty winds ranging from 45 to 64 mph persisted for several more days. Fire managers used as many as 700 firefighters and support personnel from 35 agencies and seven air tankers to battle the wildfire. A total of 6181 square acres or approximately 10 square miles were burned. The Fourmile Canyon Wildfire was the most destructive fire in Colorado history in terms of the damage to personal property. It destroyed 171 homes with an estimated cost of 217 million dollars.

11-16

In 2013…a deep southerly flow over Colorado… Ahead of a nearly stationary low pressure system over the great basin… Pumped copious amounts of monsoonal moisture into the area. In addition…a weak stationary front stretched along the Front Range foothills and Palmer Divide.  This resulted in a prolonged period of moderate to heavy rain across the Front Range foothills…Palmer Divide…urban corridor. By the 14th…storm totals ranged from 6 to 18 inches… Highest in the foothills of Boulder County. The headwaters then moved down the South Platte River and caused widespread flooding with record flood stages at several locations as it made its way downstream.  The record high flood stages resulted in widespread flooding along the South Platte River basin. The flood damage encompassed 4500 square miles of the Front Range…left 7 dead… Forced thousands to evacuate…and destroyed thousands of homes and farms. Record amounts of rainfall generated flash floods that tore up roads and lines of communication… Leaving many stranded. Nearly 19000 homes were damaged… And over 1500 destroyed. Colorado department of transportation estimated at least 30 state highway bridges were destroyed and an additional 20 seriously damaged. Preliminary assessments of the state`s infrastructure showed damage of $40 million to roads and $112 million to bridges. Repair costs for state and county roads ran into the hundreds of millions of dollars. Miles of freight and passenger rail lines were washed out or submerged… Including a section servicing Amtrak`s iconic California Zephyr. The town of Lyons was isolated by the flooding of St. Vrain creek…and several earth dams along the Front Range burst or were over-topped. Floodwaters swept through Estes Park; damaged hundreds of buildings and destroyed large sections of U.S. 34 from Loveland and U.S. 36 from Lyons to Boulder. U.S. 34 suffered the most damage… With 85 percent of its roadway and bridges destroyed. In Weld County…about nearly two thousand gas wells were damaged and had to be closed off as the floodwaters inundated entire communities. Sewage treatment plants and other utilities were knocked out in a number of towns. Governor Hickenlooper declared a disaster emergency on September 13th…in 11 counties across northeast Colorado including:  Adams…Arapahoe…Broomfield…Boulder…Denver…  Jefferson…Larimer…Logan…Morgan… Washington and Weld. By the 15th…federal emergency declarations covered those counties as well as Clear Creek County. Projected losses from the flooding statewide was nearly two billion dollars in property damage…according to Eqecat… A catastrophe modeling firm.  The damage was most severe in and around Lyons and Boulder.  More than 11 thousand people were evacuated…reportedly the largest since Hurricane Katrina. President Obama declared a state of emergency for Boulder and Larimer counties.  An additional 10 counties were added on the 16th and included: Adams… Arapahoe…Broomfield…Clear Creek…Denver…Jefferson…  Morgan…Logan… Washington and Weld counties. The president also declared a major disaster specifically for Boulder County.  There were six fatalities directly attributed to flash flooding. Two 19-yr old teenagers died on the 11th…after they were swept away by floodwaters after abandoning their car on Lindon Drive in Boulder. In Jamestown…a 72-yr old man was killed when the building he was in collapsed. An 80-yr old Lyons resident died in the early morning hours of the 12th…when his truck was swept into the St. Vrain River near his home. Later on the 12th…a 79-yr old Larimer County resident was killed when she was swept away while trying to climb to safety from her home in Cedar Point. A 61-yr old cedar point resident died when her home was swept down the Big Thompson River by the floodwaters. An 80-yr old Idaho Springs resident drowned in Clear Creek when the embankment he was standing on collapsed. In Boulder…some of the monthly records broken included: one-day all-time record: 9.08 inches which shattered the previous wettest day of 4.8 inches set on July 31… 1919; one-month record of 18.16 inches…which broke the previous all-time monthly record of 9.59 inches set in May of 1995; wettest September on record which broke the previous record of 5.5 inches set in September of 1940; one-year record of 34.15 inches broke the previous wettest year of 29.93 inches set in 1995. At Denver International Airport…the total precipitation for the month of September was 5.61 inches…which was 4.65 inches above the normal of 0.96 inches. This is the most precipitation ever recorded in Denver for the month of September. Daily precipitation records included 1.11 inches on the 12th and 2.01 inches on the 14th.

11-12

In 1974…post-frontal rain changed to snow overnight for the first snow of the season.  Snowfall totaled only 1.8 inches at Stapleton International Airport where north winds gusted to 40 mph on the 11th.  High temperature of only 46 degrees on the 12th set a new record low maximum for the date.

12

In 1887…west winds to 42 mph were recorded in the city.

In 1952…a thunderstorm outflow produced strong southeast winds gusting to 52 mph.  Surface visibility at Stapleton Airport was briefly reduced to 2 miles in blowing dust.

In 1963…a nearly stationary…white tornado near Bennett was sighted from Denver.  No damage was reported.

In 1989…an early snowfall and the first of the season brought 2 to 3 inches of slush to metro Denver.  More snow whitened the foothills west of Denver where 6 inches were measured at Evergreen.  The snow fell on leaf laden trees… And sagging branches onto power lines caused outages.  Much of Denver’s snow fell during the evening rush hour…creating traffic chaos.  Snowfall totaled 2.3 inches at Stapleton International Airport where the maximum snow depth on the ground was only 1 inch due to melting.

In 1994…thunderstorm microburst winds gusted to 67 mph in Boulder.  No damage was reported.

In 2002…a severe thunderstorm produced hail as large as 1 inch in diameter near Castle Rock.

13

In 1899…west winds were sustained to 43 mph with gusts to 46 mph.

In 1928…northwest winds were sustained to 41 mph with gusts to 45 mph.

In 1937…an apparent dry microburst produced brief north winds sustained to 31 mph with gusts to 41 mph.  There was a trace of rain.

In 1982…torrential rains drenched both the foothills and plains from Denver north.  While the heaviest rain occurred north of Denver…just east of Denver 2 1/3 inches of rain fell in 5 hours along with hail that caused minor damage to a few airplanes.  Thunderstorm rainfall totaled 0.83 inch at Stapleton International Airport.

In 1993…an upper level system combined with a cold and moist upslope flow to bring the heaviest snowfall to metro Denver for so early in the season.  Snowfall from the storm totaled 5.4 inches at Stapleton International Airport; however…most of the snow melted as it fell leaving a maximum of one inch on the ground at any one time.  North winds gusted to 21 mph at Stapleton International Airport where a record low temperature of 33 degrees for the date was observed.

In 2002…Friday the 13th proved to be bad luck for several motorists when heavy thunderstorm rainfall caused flooding on I-25 in central Denver.  Water rose several feet under the Logan Street overpass…inundating several vehicles. Some motorists were rescued…while others simply waited atop their cars for the flood water to recede.  The highway had to be closed in both directions for about 3 hours.  The flooding was exacerbated by poor drainage due to the construction along the highway.  A 12-foot drainage pipe had not yet been installed beneath the underpass.  The deluge also flooded several businesses along Broadway.

Continue reading September 12 to September 18: This week in Denver weather history →

Weather History

September 5 to September 11: This week in Denver weather history

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This Week in Denver Weather History

September is typically one of our quietest weather months and in fact it is our sunniest.  That doesn’t however mean we can’t experience weather extremes.  This week in Denver weather history we see everything from scorching heat and severe thunderstorms to snow and damaging wind.  For more about September’s weather, check out our September weather preview.

1-5

In 1995…record breaking heat occurred on the first 5 days of the month when the temperature climbed into the 90’s on each day.  Record high temperatures of 97 degrees on both the 1st and 4th equaled the all-time record maximum for the month.  High temperature of 95 degrees on the 3rd was a record for the date.  High temperatures of 94 degrees on both the 2nd and the 5th were not records.  The low temperature of 64 degrees on the 4th equaled the record high minimum for the date.

1-7

In 1978…the temperature reached 90 degrees or more on seven consecutive days with the highest temperature…94 degrees… Recorded on both the 4th and 6th.

3-6

In 1909…rainfall for the 4 days accumulated to 3.97 inches in Boulder…while in Denver rainfall totaled 2.45 inches on the 4th…5th…and 6th.

5

In 1899…the highest recorded temperature in September…97 degrees…occurred.  The same temperature was also reached on September 4…1960…and September 1 and 4…1995.

In 1940…a severe wind and hail storm confined mostly to the west and north parts of the city occurred shortly after 4:30 pm.  Hail stones ranged in size from 1/4 to 1/2 inch in diameter. In north Denver…hail piled to a depth of 4 inches.  Flooding occurred in one underpass…which stalled 2 cars.  One girl was injured when the weight of the hail flattened a porch on which she stood. Northeast winds were sustained to 29 mph with gusts to 32 mph in downtown Denver.

In 1987…a thunderstorm complex produced hail as large as 1 3/8 inches in diameter…2 miles east of Buckley Field in Aurora.  No damage was reported.

5-9

In 1988…layers of smoke aloft from large forest fires in Yellowstone National Park completely obliterated the sun at times.  At Stapleton International Airport…surface visibility was reduced at times to 5 and 6 miles in smoke.

5-13

In 2010…the Fourmile Canyon Wildfire…northwest of Boulder… broke out on the morning of the 5th. It originated from an unattended fire pit at a local residence. The wildfire quickly consumed 5 1/2 square miles or 3500 acres the first day…and forced the evacuation of over three thousand residents. Erratic 45-mph gusts sent the fire in two directions at times. Very dry weather conditions preceded the fire. The combination of strong winds…low relative humidities and dry fuels allowed the wildfire spread rapidly through the steep…heavily forested terrain. The flames were reportedly 20 to 50 feet in length. Towns within the burn area included Salina…Wallstreet and Gold Hill. The dry conditions coupled with gusty winds ranging from 45 to 64 mph persisted for several more days. Fire managers used as many as 700 firefighters and support personnel from 35 agencies and seven air tankers to battle the wildfire. A total of 6181 square acres or approximately 10 square miles were burned. The Fourmile Canyon Wildfire was the most destructive fire in Colorado history in terms of the damage to personal property. It destroyed 171 homes with an estimated cost of 217 million dollars.

6

In 1940…a thunderstorm pelted the city with small hail. The storm produced some lightning damage.  One woman was stunned by a bolt which struck near her.  Heavy rain from the storm raised the level of Cherry Creek by more than 3 feet during the height of the storm.  Rainfall downtown was only 0.26 inch.

In 1988…strong winds blew down two houses that were under construction in Castle Rock.  Northwest winds gusted to 44 mph at Stapleton International Airport.

In 1993…a man was struck and killed by lightning while standing outside his home in unincorporated Arapahoe County 11 miles south of Denver.  Lightning also struck a cabin in Marshdale…20 miles southwest of Denver…which started a fire and damaged one room and a portion of the roof.

In 1995…hail as large as 3/4 inch in diameter fell in Coal Creek Canyon in northern Jefferson County.

In 2001…a thunderstorm dropped 3/4 inch diameter hail in Aurora near Cherry Creek.

7

In 1875…the creeks were running dangerously high during the night from heavy rains in the mountains.

In 1885…a thunderstorm produced very white hail of irregular shape and about the size of beans.  Precipitation was only 0.10 inch.

In 1971…a vigorous cold front accompanied by a thunderstorm produced wind gusts to 48 mph at Stapleton International Airport and much upslope cloudiness and light rain across metro Denver.

In 1989…widespread thunderstorms produced lightning strikes that knocked out power to about 13 thousand homes in Boulder County. In a rugged area stripped of vegetation by a forest fire earlier in July…heavy rain triggered mud slides that destroyed one home and severely damaged another in Boulder canyon 10 miles west of Boulder. In one home…the mud caved in an exterior wall and poured into the residence only seconds after 2 people had evacuated the premises. Rainfall totaled 1 to 3 inches.  Hail 1 3/4 inches in diameter fell in Nederland…Idaho Springs…and Golden Gate Canyon.  Hail 1 inch in diameter was measured 10 miles north of Golden.

In 1993…thunderstorm winds toppled an overhead sign onto the intersection of I-70 and I-25 in Denver…causing considerable damage to 4 vehicles.  The winds also caused a police car to be blown off the road northeast of Denver. Thunderstorm winds gusting to 66 mph damaged the siding of a residence southeast of Brighton.  A thunderstorm wind gust to 53 mph was recorded at Stapleton International Airport.  Hail to 7/8 inch in diameter fell at Kittredge in the foothills of Jefferson County.

In 1994…lightning severely damaged a public television transmitter atop Squaw Mountain west of Denver.

7-8

In 1884…a windstorm from mid-afternoon until the early morning hours of the 8th produced south winds sustained to 48 mph.  The strong winds toppled several trees in the city.

In 1892…there was a trace of rainfall each day.  This together with a trace of rain on both the 2nd and 3rd was the only rainfall of the month…making the month the driest on record.  The record was equaled in 1944.

Continue reading September 5 to September 11: This week in Denver weather history →

Weather History

August 29 to September 4: This week in Denver weather history

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This Week in Denver Weather History

Certainly this time of year we start to see temperatures drop and the conditions moderate.  This is usually one of Denver’s most pleasant times of years when the heat of summer fades and the snow and cold of winter is still far away.  That however wasn’t the case when the most notable event in Denver weather history this week occurred.  It was in 1961 on the 3rd of September that Denver received its earliest measurable snowfall – 4.2 inches!

19-30

In 1875…grasshoppers appeared in great numbers at 10:00 am on the 19th.  Thousands landed on the ground.  The streets were literally covered with them.  Swarms of grasshoppers were seen on each day.  All gardens in the city were devastated…and in the countryside the grasshoppers were very destructive to ripened grain.  On the 30th the grasshoppers were so numerous as to almost darken the sun.

29

In 1876…after the passage of a gentle rain shower to the east during the late evening hours…the moon shone brightly and a remarkably bright lunar rainbow appeared.

In 1910…an apparent cold front produced sustained northeast winds to 40 mph.

In 1946…the high temperature warmed to only 55 degrees…the record low maximum for the month.

In 1989…a spectacular lightning display knocked out power to 300 blocks in southeast Denver.  One bolt started a fire in a lumber yard in the northeast part of the city…and the attic of a home in the same area was set ablaze by a lightning bolt.

In 1996…3/4 inch diameter hail was measured in Parker.

In 2000…lightning struck two homes in Thornton.  The extent of damage was unknown.

In 2002…two small tornadoes caused damage in southeast metro Denver.  The first tornado…associated with a multi-vortex storm…touched down briefly near E-470 and South Jordan Road.  Some fences were damaged…and a few trees were blown down.  A few of the homes also sustained minor roof damage. Damage from this storm totaled 100 thousand dollars.  The second tornado associated with the storm touched down in a subdivision that was under construction at Gartrell and Arapahoe roads.  Four large condominiums under construction were destroyed.  The most heavily damaged portions of the structures were still in the framing stages.  Adjacent sections where enclosed walls were in place were not destroyed.  A man suffered 4 broken ribs and several cuts and bruises when the trailer he sought shelter in was flipped three times and torn apart by the twister.  Damage from this storm totaled 6 million dollars. A severe thunderstorm produced 1 inch diameter hail near Evergreen.

In 2006…severe thunderstorms produced large hail in the foothills west of Denver.  Hail to 1 inch in diameter fell near Blackhawk.  Hail as large as 7/8 inch was measured near Idaho Springs…along with 3/4 inch hail near Nederland and Conifer.

30

In 1981…60 mph winds were reported in Boulder.

In 2004…a severe thunderstorm produced hail as large as 1 inch in diameter in south Aurora near Cherry Creek.

31

In 1951…hail as large as 1 3/4 inches in diameter caused an estimated 300 thousand dollars damage in metro Denver. Hail as large as 1 1/2 inches in diameter was measured at Stapleton Airport.

In 1978…strong thunderstorm winds tore the roof off an apartment building in Aurora…downed trees…and damaged windows in Denver.  A microburst wind gust to 58 mph was recorded at Stapleton International Airport.

In 1985…a thunderstorm wind gust to 60 mph was clocked at Buckley Field in Aurora.

In 1997…hail to 1 1/4 inches in diameter was measured in Aurora.

In 2006…a female postal worker was struck and injured by lightning while delivering mail in Westminster.

In 2008…lightning struck a home in Brighton…damaging the roof and a bedroom.  The damaged totaled 20 thousand dollars.

1

In 1951…large hail pounded Boulder…causing thousands of dollars in damage to roofs and automobiles.  Heavy thunderstorm rainfall flooded basements and produced widespread street flooding.

In 1966…severe thunderstorms caused local flooding in areas from Denver to the north and east.  There was scattered damage from hail and lightning.  Streets were flooded in Boulder…and streets and basements were flooded in several areas of metro Denver.  The public reported 1 inch diameter hail in Aurora and near Cheery Creek Reservoir. Thunderstorm rainfall totaled only 0.39 inch at Stapleton International Airport.

In 1985…severe thunderstorms dumped heavy rain and hail at many locations along the Front Range from Denver south. The southern and eastern suburbs of metro Denver were especially hard hit.  Rainfall from 1 1/2 to 3 inches caused extensive street flooding in Aurora where two creeks rose out of their banks.  Two homes in the city suffered minor lightning damage.  Almost 4 inches of rain fell in the Parker area.  Hail up to ping-pong ball size piled up to a foot deep and closed a road in Evergreen. Hail as large as 1 3/4 inches in diameter was reported 8 miles northeast of Deckers.  Wind gusts to 65 mph were estimated in southeast Aurora.

In 1990…marble size hail piled up to 2 inches deep in the foothills community of Kittredge…18 miles southwest of Denver.  As much as half an inch of rain fell in just 15 minutes and caused minor road and small stream flooding. A thunderstorm dropped pea to marble size hail and brief heavy rain near Ward road and 64th avenue in Arvada. Minor street and small stream flooding was reported in the area.

In 1995…a strong thunderstorm microburst with only a few drops of rain produced a recorded wind gust to 85 mph at the site of the former Stapleton International Airport. The wind gust occurred at 8:30 pm MDT.  The all-time highest recorded temperature in September…97 degrees…occurred.  The same temperature also occurred on September 5…1899…September 4…1960…and September 4… 1995.
1-5

In 1995…record breaking heat occurred on the first 5 days of the month when the temperature climbed into the 90’s on each day.  Record high temperatures of 97 degrees on both the 1st and 4th equaled the all-time record maximum for the month.  High temperature of 95 degrees on the 3rd was a record for the date.  High temperatures of 94 degrees on both the 2nd and the 5th were not records.  The low temperature of 64 degrees on the 4th equaled the record high minimum for the date.

1-7

In 1978…the temperature reached 90 degrees or more on seven consecutive days with the highest temperature…94 degrees… Recorded on both the 4th and 6th.

2

In 1938…heavy cloudbursts in the foothills near the top of Genesee mountain caused flash flooding on bear creek at Morrison.  Nearly 8 inches of rain fell just north of Morrison in 6 hours and drowned 6 people in a car between Morrison and Kittredge.  Damage was estimated at nearly a half million dollars.  Flash flooding also occurred on South Boulder Creek in Eldorado Springs. Rainfall totaled 4.42 inches in Eldorado Springs…and rainfall was estimated to more than 6 inches in the foothills west of the town.  Many buildings and residences were damaged in Eldorado Springs…and bridges were swept away.  The high waters forced residents from their homes as far downstream as Erie.  This was the flood of record on south Boulder creek.

In 1973…hail to 3/4 inch diameter was reported in Boulder.

In 1987…lightning struck two men who were standing under a tree in downtown Denver.  Both were seriously injured and hospitalized.

In 1996…lightning sparked a brush fire in the south buffer zone of the Rocky Flats Environmental Test Facility.  No structures were damaged…but the fire burned about 100 acres of grassland before being contained.

2-3

In 1892…there was a trace of rainfall each day.  This… Together with a trace of rain on both the 7th and 8th…was the only rainfall of the month…making the month the driest on record.  The monthly record was equaled in 1944.

3

In 1901…a thunderstorm produced rain…hail of unknown size… And south winds sustained to 40 mph with gusts to 43 mph.

In 1961…Labor Day snow storm is the earliest date of the first snow…trace and measurable…of the season.  The heavy wet snow broke many limbs from trees that were still in full foliage.  The storm produced 4.2 inches of snowfall at Stapleton Airport with nearly a foot of snow in western suburbs and in the foothills.  Minimum temperature of 33 degrees was a record for the date and the coldest ever recorded so early in the season.

In 1999…severe thunderstorms dumped large hail across metro Denver.  Hail as large as 1 inch in diameter was measured near Cherry Creek in Aurora and near Bennett.  Hail to 3/4 inch in diameter fell in the city of Denver.

In 2002…a thunderstorm produced a wind gust to 51 mph at Denver International Airport.

In 2003…very heavy thunderstorm rain washed out parts of the Virginia Canyon Road above Idaho Springs.  Up to 4 feet of mud reportedly washed down the road during the storm.  Several vehicles were trapped on the road.  In Idaho Springs…several streets…including the main street… Were also buried in mud and gravel.  Some buildings in town experienced minor flooding…including the basement of the town library and the police station.

3-6

In 1909…rainfall for the 4 days accumulated to 3.97 inches in Boulder…while in Denver rainfall totaled 2.45 inches on the 4th…5th…and 6th.

Continue reading August 29 to September 4: This week in Denver weather history →

Weather History

August 22 to August 28: This week in Denver weather history

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This Week in Denver Weather History

Lightning is a very real danger here in Colorado.  The outdoor-centric lifestyle we lead oftentimes puts us in situations when we are better off heading for cover.  The dangers of not properly taking shelter when lightning is in the area are highlighted by a number of events in our look back at this week in Denver weather history.

19-30

In 1875…grasshoppers appeared in great numbers at 10:00 am on the 19th.  Thousands landed on the ground.  The streets were literally covered with them.  Swarms of grasshoppers were seen on each day.  All gardens in the city were devastated…and in the countryside the grasshoppers were very destructive to ripened grain.  On the 30th the grasshoppers were so numerous as to almost darken the sun.

22

In 1898…an apparent thunderstorm produced southwest sustained winds to 40 mph with gusts to 43 mph.

In 1903…a late afternoon thunderstorm produced rain…hail… And east winds sustained to 40 mph with gusts to 44 mph.

In 1904…the lowest recorded temperature in August…40 degrees…occurred.  The same temperature also occurred on three consecutive days…August 24…25…and 26 in 1910.

In 1965…heavy rain and hail caused some damage from flooding over northern Douglas County from Castle Rock to Franktown.

In 1981…thunderstorms moved across metro Denver.  At least 5 funnel cloud sightings were reported.  Funnel clouds were seen at 96th Ave. And Sheridan Blvd. and at 92nd Ave. and Federal Blvd. In Westminster and 7 miles north of Stapleton International Airport.  Lightning injured two people in Boulder.  A quarter inch of rain fell in just 5 minutes in Brighton.  Up to 3/4 inch of rain doused Parker in 30 minutes.

In 1983…3/4 inch diameter hail was reported at Kittredge… Along with 0.60 inch of rain in 25 minutes.

In 1984…a thunderstorm dumped 4 inches of rain on Brighton in 90 minutes…causing extensive street flooding in the downtown area.

In 1987…over an inch of rain fell in 24 hours throughout most of metro Denver.  A public library suffered water damage to the ceiling…carpet…and a few books.  Rainfall was 0.76 inch at Stapleton International Airport.

In 1990…lightning knocked out power to about 2500 homes in Lakewood for about an hour.

In 1991…National Weather Service personnel at Stapleton International Airport sighted an apparent tornado briefly on the ground 3 miles west-northwest of the airport.  No damage was reported.

In 1995…lightning struck 3 electrical power substations in Louisville.  Residences of more than 4500 people were without power from 30 minutes to more than an hour.

In 1996…between 1 and 3 inches of rain fell across metro Denver.  As a result…several low lying areas were flooded. A bicyclist was swept into a fast moving creek when he tried to cross a flooded bike path.  The man was washed downstream about 15 feet before getting snagged by a tree stump.  He and a man who tried to rescue him received minor injuries.  The heavy rain caused numerous power outages…false fire alarms…and traffic accidents. In Lakewood…telephone service to around 60 thousand residents was knocked out when a switching center was flooded.  Funnel clouds were sighted near Chatfield Reservoir and Highlands Ranch.

In 2000…lightning sparked a blaze which gutted a 10-unit apartment building in Highlands Ranch.  Twenty-eight people were left homeless.  Damage was estimated at 2 million dollars.

In 2007…severe thunderstorms produced large hail…up to 1 1/4 inches in diameter…in the vicinities of Castle Rock… Elizabeth and Franktown.

In 2013…flash flooding occurred in central Douglas County with numerous road closures reported. One of the closures occurred at the Tomah Road exit along I-25…south of Castle Rock. The closure backed up all I-25 the way to Castle Rock. At Denver International Airport…1.94 inches of precipitation was recorded…which set a new record rainfall for the date. The old record was 0.75 inches… set back in 1953.

22-24

In 1987…some locations in metro Denver had a total 3-day rainfall of 2 to 4 inches.  Rainfall totaled 0.96 inch at Stapleton International Airport.

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In 1900…northwest winds were sustained to 42 mph with gusts to 49 mph.

In 1921…a thunderstorm cloudburst produced 2.20 inches of rainfall in an hour over downtown Denver.  This is the greatest 1 hour rainfall on record at the official observing site in the city.  Precipitation totaled 2.93 inches…which is the greatest calendar day precipitation ever recorded in August.

In 1941…one man was killed by lightning about 2 miles from the official weather station in downtown Denver.

In 1962…a home near Boulder was destroyed by a lightning- caused fire.

In 1968…strong winds buffeted Boulder briefly during the early morning hours.  At the National Center for Atmospheric Research…winds averaged 55 mph with gusts to 85 mph.  Damage was minor.  Northwest winds gusted to 31 mph at Stapleton International Airport.

In 1977…lightning damaged at least 6 homes in Aurora.

In 2008…a landspout touched down near Westcreek in Douglas County.  One man was seriously injured when he tried to escaped several falling trees in his ATV.  One of the trees struck his back and broke two vertebrae.  Another camper narrowly escaped injury.  Seconds after he back up his truck…a tree came down where it had been parked.

Continue reading August 22 to August 28: This week in Denver weather history →