Heavy rain, flooding, lightning, tornadoes and hail are not at all uncommon this time of year and we see plenty of those types of events in our look back at this week in Denver weather history. Probably one of the most notable events occurred in 2001 when a thunderstorms with large hail ripped through Denver International Airport causing $10 million in property damage and damaged dozens of airplanes.

From the National Weather Service:

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In 2012…it was the hottest June in Denver since weather records began back in 1872. The average temperature for the month was 75.0 degrees which was 7.6 degrees above normal. There were a total of seventeen 90 degree days in the month of June. The highlight of record setting month was a stretch of five consecutive 100 degree days from the 22nd to the 26th. This was only the third time in Denver weather history in which this happened. Two of the high temperatures during the stretch peaked at 105 degrees…which set the all time record for the month of June and tied the all time maximum temperature for Denver.

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In 1964…high winds at speeds of 50 to 60 mph with gusts as high as 75 mph caused damage to homes…power lines…and trees in Boulder. Non-convective west winds gusting to 46 mph caused some blowing dust at Stapleton International Airport on the 17th.

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In 1875…a windstorm produced sustained winds to 45 mph during the morning hours. Numerous forest fires along the base of the mountains were visible from the city.

In 1886…northwest winds sustained to 40 mph were the strongest of the month that year.

In 1987…severe thunderstorms produced lightning…large hail… A tornado…heavy rain…and strong winds across metro Denver. Rainfall totaled 2.50 inches in an hour in Wheat Ridge… Causing minor flooding. I-25 was flooded in north-central Denver…snarling traffic. Hail 7/8 inch in diameter fell in Louisville with 1 1/2 inch hail near Golden and 1 to 1 3/4 inch hail in and near Castle Rock. A tornado touched down briefly in Castle Rock. No damage was reported. Lightning started a small fire that burned half a cabin near Evergreen.

In 1994…a funnel cloud was sighted over Aurora; hail to 1 3/4 inch diameter fell near Brighton; and hail over an inch in diameter fell over Aurora…southeast Denver… Louisville…and Boulder. Lightning struck a home in Henderson 9 miles north of Denver and knocked a hole in the roof…which caused the ceiling to collapse. Hail to 1 1/4 inch diameter was measured at Stapleton International Airport.

In 2002…the Hayman wildfire in the foothills to the southwest of Denver intensified…and the winds aloft carried the smoke plume directly over metro Denver…again creating a dense haze of smoke which blocked the sun. Surface visibilities were again reduced to as low as 1 1/4 miles at Denver International Airport.

In 2004…severe thunderstorms produced hail to 3/4 inch in diameter near Morrison…in Littleton…near Conifer…near Castle Rock…and in Aurora near Cherry Creek.

In 2013…a landspout tornado touched down at DIA. The tornado sent 10 thousand travelers on the concourse…on planes and in the terminal scrambling to get into tornado shelters. The tornado formed just to the south of Runway 35R and then moved slowly northwest between Runway 35R and 35L…and moved to within one third of a mile of Concourses A and B before dissipating. The tornado moved extremely close if not over the ASOS (Automated Surface Observation System) and another low level wind shear sensor at DIA. The ASOS weather observing system reported a 97 mph wind gust…while the wind shear sensor reported a wind gust to 109 mph at the same time indicative of an EF1 tornado. There was only minor damage noted to the equipment. Nine flights were diverted elsewhere during a tornado warning. Severe thunderstorms also produced large hail up to quarter size in Adams and Weld Counties.

In 2014…a severe thunderstorm produced large hail up to quarter size near Buckley Air Force Base.  At Denver International Airport…a peak wind gust to 55 mph was observed from the southwest…along with 0.37 inches of water.

In 2015…a severe thunderstorm produced hail…from 1 to 1 3/4 inches in diameter…near Lafayette…Louisville and Superior.

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In 1874…during the afternoon… Large columns of smoke from extensive fires in the mountain forests moved over the city from the west and southwest.

In 1875…while no precipitation was measured in the city… Rainfall over the Palmer Divide caused Cherry Creek to rise to the highest level in 10 years.

In 1977…hail up to 2 inch diameter damaged two patrol cars in Castle Rock.

In 1983 golf ball size hail fell just north of Bennett.

In 1990…lightning from a thunderstorm struck the roof of a house in south Boulder. Residents of the house were able to extinguish the ensuing fire with a garden hose…but not before several shingles had burned.

In 1992…thunderstorms produced hail up to 2 inches in diameter in central Douglas County near Castle Rock. Hail was 3 inches deep on I-25 south of Castle Rock. A funnel cloud was sighted near Parker.

In 1997…a 66-year-old man was knocked unconscious by a bolt of lightning while he was golfing at the eagle country club in Broomfield.

In 2000…dry microburst winds gusting to near 70 mph were reported across southeast Boulder and northern Jefferson counties. Peak wind gusts included: 68 mph at the national wind technology center…67 mph at Jefferson County airport… And 65 mph in Broomfield.

In 2001…severe thunderstorms produced large hail in the foothills southwest of Denver. Hail as large as 1 3/4 inch in diameter fell near conifer and Bailey.

In 2002…lightning damaged the Evergreen fire protection district radio repeater. One microwave transmitter…the main fire channel transmitter…and two solar panel controllers were destroyed. Lightning struck a garage and caused a small fire. Two vehicles parked in the garage were damaged. Hail to 3/4 inch in diameter fell near Castle Rock.

In 2004…severe thunderstorms produced hail to 3/4 inch in diameter near Castle Rock…Larkspur… And Golden.

In 2018…very large hail pummeled portions of the Front Range Urban Corridor and extended across the northeast plains of Colorado. Reports of collapsed roofs due to hail were reported…with major hail portions of the Denver metro area. The Rocky Mountain Insurance Information Association estimated the property damage from the storm totaled 276.4 million dollars…making it the 8th costliest hailstorm to strike the state to date. In Denver and the surrounding metro area…hail sizes included: 3 inch diameter in Englewood; 2 3/4 inch in Greenwood Village; 2 inch at Aurora Cherry Creek…4 miles south of Glendale and near Smoky Hill; 1 3/4 inch just east of Denver International Airport and near South Glenn; 1 1/2 inch near Niwot; and 1 inch diameter hail in Southwest Denver and 5 miles northeast of Parker.

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In 1875…smoke from several large forest fires in the mountains was visible from the city on each of these days.

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In 1888…northwest winds were sustained to 44 mph.

In 1956…a microburst caused a brief wind gust to 58 mph at Stapleton Airport.

In 1964…hail up to 1 inch in diameter was reported 1 mile north of Stapleton International Airport. A 3 minute hail storm at both Stapleton International Airport and lowry field piled small hail to one half inch deep.

In 1967…a strong thunderstorm dumped 1.95 inches of rain in less than an hour at Stapleton International Airport and produced a wind gust to 54 mph. The storm caused some flooding in east Denver and Aurora. There was widespread flooding to streets…basements… And store buildings and automobiles. Hail stones to 3/4 inch in diameter were measured at Buckley Field in Aurora. A tornado touched down just south of Littleton…damaging a barn and killing several head of cattle.

In 1985…a wind gust to 61 mph was reported at Golden Gate Canyon in the foothills west of Denver.

In 1986…a man was killed by lightning at Highlands Ranch south of Denver.

In 1987…several tornadoes were sighted across metro Denver. A tornado touched down briefly 5 miles west of Parker. A tornado was sighted just north of Chatfield Reservoir. A tornado just northwest of Watkins was on the ground for 15 minutes. A tornado near Barr Lake was taped by a television news crew. It had a double vortex and was on the ground for about 10 minutes. In addition to the 4 tornadoes…severe thunderstorms dumped large hail across metro Denver. One inch hail was reported in southeast Aurora; 3/4 inch hail fell at the Denver Technology Center…Buckley Field… And Franktown.

In 1992…several short-lived tornadoes occurred in the vicinity of Barr Lake. No injuries or damages were reported. A water spout was sighted over the southern end of Barr Lake. Funnel clouds were also sighted on the grounds of the rocky mountain arsenal by national weather service observers at Stapleton International Airport.

In 1994…hail up to dime size covered I-25 south of Denver and near Sedalia. Heavy rain caused local flooding on the interstate Highway.

In 1996…strong thunderstorm winds downed several large tree limbs in Boulder on the University of Colorado campus. A stop light in the city was also blown down.

In 1999…lightning sparked an oil tank fire near Brighton.

In 2001…large hail driven by strong thunderstorm winds raked Denver International and Front Range airports. Wind gusting to 54 mph along with hail as large 2 inches in diameter punched at least 14 thousand holes and cracks in the flat roofs of several buildings at Denver International Airport. In addition…93 planes and hundreds of cars were damaged. About 100 flights had to be cancelled…stranding 1500 travelers. The airport was completely shut down for about 20 minutes. The storm also damaged a ground avoidance radar used to track planes on the ground to prevent collisions. Damage was estimated at 10 million dollars…not counting the damage to the 93 airliners. The storm moved south and struck Watkins with hail as large as 2 1/2 inches in diameter and winds gusting to 60 mph. A least 30 private planes at Front Range airport were destroyed. The radome protecting the National Weather Service Doppler radar…which was tracking the storm…also sustained damage. The large hail…damaging winds… And heavy rain pummeled a mobile home park near Watkins. In the park…52 mobile homes… 14 recreational vehicles…3 homes… And a commercial building were damaged. Siding was riddled with holes and windows were broken. Vehicles sustained extensive damage and car windows were shattered. A handful of people were treated for minor cuts and bruises. The strong winds also flipped a tractor trailer along I-70 near Watkins. The storm caused power outages…which affected about 1200 residents. Excluding the damage at Denver International Airport…damage estimates totaled 49 million dollars…making the storm the costliest in the last 3 years and the 10th costliest since 1984. A small tornado touched down just east of Brighton… But did no damage. Hail as large as 2 inches in diameter fell near Fort Lupton with 3/4 inch hail measured in Bennett. Precipitation from the storm totaled only 0.23 inch at Denver International Airport.

In 2002…heavy rain fell near the Hayman wildfire burn area. Flash flooding washed out a 40-foot section of the access road to Cheeseman Reservoir. Some debris was washed against a gate…blocking the road. Hail to 1 1/2 inches in diameter fell near central city with 3/4 inch hail near Blackhawk.

In 2003…hail as large as 1 inch in diameter fell near Bennett and Strasburg with 3/4 inch hail measured in Denver…Golden… At Centennial Airport…and near Parker. Hail as large as 7/8 inch was reported in Arvada.

In 2004…a severe thunderstorm produced hail to 3/4 inch in diameter in and near Brighton.

In 2005…severe thunderstorms produced large hail near the palmer divide. Hail to 1 inch in diameter was measured near larkspur with 7/8 inch hail near Sedalia and 3/4 inch hail in Greenland. An apparent thunderstorm outflow produced a wind gust to 59 mph at Denver International Airport during the evening hours.

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In 1897…high winds raked the city overnight. Southeast winds were sustained to 60 mph with gusts as high as 72 mph on the 20th. Southeast winds were sustained to 57 mph with gusts to 60 mph on the 21st.

In 2007…a brief hot spell produced two temperature records. The high temperature of 97 degrees was tied on the 20th. A new record high temperature of 99 degrees was established on the 21st.

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In 1927…north winds were sustained to 40 mph with gusts to 44 mph.

In 1984…lightning struck and killed two children standing near a tree in a backyard in Lakewood. Strong thunderstorm downbursts caused a wind gust to 58 mph in Northglenn and knocked down two power poles near Brighton.

In 1988…lightning struck a home in Denver… Causing about ten thousand dollars damage. Lightning damaged 3 homes in Littleton…and also hit a house in greenwood village that had been struck by lightning 7 years previously.

In 1991…thunderstorms produced widespread hail across metro Denver. Hail as large as 2 1/2 inches fell at several locations across southwest metro Denver. One storm spotter reported hail 8 inches deep near the intersection of I-25 and c-470. Heavy rain with the storms caused some street flooding. In Commerce City…several cars were under water… And in Westminster a police officer reported water up to the doors of his car. Damage to homes and automobiles totaled 55 million dollars.

In 1992…a tornado touched down briefly near Bennett. Another tornado was briefly on the ground near Strasburg.

In 1994…heavy thunderstorm rains caused flooding in metro Denver. Several vehicles were stalled in the high water on I-25. Lightning struck an underground natural gas line in Aurora…causing a fire. Widespread power outages were also observed.

In 1996…three homes were struck by lightning in Parker. The lightning struck the garage of the first home…which started a small fire that burned some siding and spread into the attic. A second home sustained damage to the attic when a small fire was started. The third home received only minor damage. Lightning also sparked two small grass fires in the area. A man in Lakewood received minor injuries when he was struck by lightning while working on a ladder. A funnel cloud was sighted in Castle Rock. Strong thunderstorm winds downed a large tree near crossroads mall in Boulder. A small tornado (F0) briefly touched down near Lafayette. No damage was reported.

In 1997…one inch diameter hail was measured in Boulder.

In 2002…a thunderstorm wind gust to 62 mph was recorded at Denver International Airport.

In 2005…severe thunderstorms produced hail to 1 inch in diameter in Broomfield along with 3/4 inch hail near Arvada.

In 2006…a man riding a motorcycle was struck and killed by lightning on U.S. Highway 36 between church ranch blvd. And Sheridan Blvd in Westminster. After the biker was struck…he and his motorcycle crashed into the center concrete median of the highway. The lightning bolt left a crater in the highway asphalt that measured 18 inches long…8 inches wide and 4 inches deep.

In 2010…s severe thunderstorm produced hail up to 1 1/2 inches in diameter near Morrison. In Lafayette and Louisville…hail up to one inch in diameter was observed.

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In 1941…strong thunderstorms produced cloudbursts of rain in Boulder County…starting during the late evening of the 21st and continuing overnight. The heavy rains over the Boulder Creek…Left Hand Creek… And south St Vrain River basins produced flooding in already swollen streams and turned dry gulches into raging torrents. The force of the floodwaters swept a man from the arms of his wife to his death…severely damaged canyon homes and swept others away… And hurtled a car down a steep embankment after the driver narrowly escaped. West of Boulder…the Boulder canyon highway was littered with rocks and debris and collapsed when two culverts were washed away. The flood waters washed much debris down four mile canyon…damaging the road near the creek bed. A bridge over dry creek just south of Niwot was completely washed away.

In 1964…scattered hail and rain caused property damage and local flooding in Boulder.

In 1989…an unseasonably cold weather system produced strong winds over much of metro Denver and snowfall in the foothills as low as 7500 feet elevation. One to 6 inches of snow fell in the foothills west of Denver with 15 inches reported on the summit of Mount Evans. Six inches of snow were measured at conifer. Rainfall totaled only 0.09 inch at Stapleton International Airport where northwest winds gusted to 29 mph on the 21st.

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In 1872…small sandstorms…frequently seen on the prairie… Occasionally passed through the city.

In 1983…3/4 inch hail was observed at Deckers… And a thunderstorm produced wind gusts to 55 mph at Littleton.

In 1988…a tornado was spotted one mile east of Brighton; it remained on the ground for about 6 minutes…but did no reportable damage. Lightning damaged a home near Castle Rock.

In 1991…thunderstorms produced golf ball size hail in Lafayette. The strongest storms occurred north of metro Denver.

In 1992…nickel size hail was reported just east of Parker.

In 1995…large hail 3/4 to 1 3/4 inches in diameter fell in Castle Rock where a funnel cloud was sighted. Hail 3/4 inch to 1 inch in diameter fell in south Denver and Aurora. A funnel cloud was also sighted over Chatfield Reservoir. In Bennett…very strong dry microburst winds of unknown speeds ripped a 14- by 48-foot metal roof off of a barn. The roof was tossed approximately 250 yards. A few 150- pound railroad ties were moved 10 to 15 feet.

In 1997…a tornado touched down near the Adams County Fairgrounds northeast of Denver…uprooting several trees and damaging a car. A dry microburst produced a brief wind gust to 69 mph at Jefferson County airport. A small brief tornado was sighted near Hudson…but did no reported damage.

In 1998…3/4 inch hail fell near Hudson.

In 1999…thunderstorm winds gusted to 63 mph at Denver International Airport.

In 2003…hail as large as 2 inches in diameter was measured in Fort Lupton with 3/4 inch hail in
Erie and near Boulder.

In 2006…a small tornado (f0) touched down near Franktown… But caused no damage.

In 2008…strong winds from dry microbursts developed over parts of southern weld and western Arapahoe counties. A peak gust of 60 mph was observed in Centennial. Near Frederick…strong winds snapped 3 power poles and sparked a small grassfire near State Highway 52 and Interstate 25. At Denver International Airport…a peak gust of 31 mph was observed.

In 2009…hail up to 2 inches in diameter was observed near crescent in Boulder County.

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In 1874…a thunderstorm pelted the city with hail and brief heavy rain. Rainfall was 0.30 inch in 10 minutes. Total rainfall was 0.36 inch for the day. Hail to 1/4 inch in diameter destroyed the strawberry fields near the limits of the city. The thunderstorm dropped the temperature from 93 degrees to 80 degrees in 5 minutes.

In 1887…north winds were sustained to 42 mph.

In 1954…the temperature climbed to a high of 102 degrees… Setting a record for the date.

In 1962…lightning struck and injured a man near buffalo… Southwest of Denver…while he was riding in the back of a pick-up truck. He suffered multiple bruises…cuts… And shock.

In 1965…an apparent tornado was reported 18 miles east of Denver. No damage was reported.

In 1975…hail up to 3/4 inch in diameter fell at Stapleton International Airport and over other parts of metro Denver. Four funnel clouds were sighted: 10 miles northeast of Denver…south of Boulder…southeast of Boulder… And south of Aurora.

In 1976…heavy rain and eroding water collapsed a retaining wall in Thornton.

In 1981…a thunderstorm produced wind gusts to 60 mph in Littleton.

In 1982…two separate bolts of lightning injured three men in southwest Denver. Two buildings were slightly damaged.

In 1987…severe thunderstorms produced large hail across metro Denver. Golf ball size hail fell in Littleton…near Morrison…and in southeast Aurora with 1 1/2 inch hail recorded in south Lakewood and 1 inch hail reported in Littleton…Arvada… And at Cherry Creek dam. Two funnel clouds were sighted 20 miles southwest of Stapleton International Airport.

In 1993…non-convective high winds developed along the Front Range foothills. Wind gusts to 70 mph were common near the foothills with numerous tree limbs broken by the winds. North winds gusting to 36 mph were recorded at Stapleton International Airport.

In 1999…hail as large as 1 inch in diameter was measured in the city of Denver with 3/4 inch hail in Littleton.

In 2001…a severe thunderstorm produced large hail in south metro Denver. Hail as large as 1 1/2 inch in diameter fell in Littleton with 1 1/4 inch hail near Sheridan.

In 2009…hail up to 1 inch in diameter was observed near Parker. At Denver International Airport…a total of 1.64 inches was measured in a 24-hr period…setting a new record for the date.

In 2016…a severe thunderstorm produced a peak wind gust to 60 mph near Strasburg.

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In 1873…there was a great deal of smoke from a fire in the mountains to the southwest of the city during the late afternoon.

In 1875…smoke from forest fires in the mountains to the southwest could plainly be seen from the city.

In 1958…a strong cold front produced a north wind gust to 55 mph at Stapleton Airport where blowing dust briefly reduced the visibility to 1 mile.

In 1982…one inch diameter hail pelted west Denver. A half inch of rain drenched the suburb of Englewood in 10 minutes. Hail piled up to 5 inches deep…snarling rush hour traffic and damaging some stores in a shopping center when the roof started leaking.

In 1988…lightning destroyed the chimney of a house near Evergreen. Another bolt demolished a radio transmitter in the area.

In 1989…golf ball size hail cut a swath 2 1/2 miles wide through open country 14 miles southwest of Bennett. The storm also dropped 1.75 inches of rain on the area. Hail to 3/4 inch in diameter damaged the car of a storm chaser just south of Bennett.

In 1996…a funnel cloud was sighted near Hudson where hail up to 1 3/4 inch diameter fell. Lightning struck a home in Littleton…which sparked a small fire on the roof. Thunderstorm wind gusts to 64 mph were recorded in Castle Rock.

In 2005…severe thunderstorms produced large hail across metro Denver. Hail as large as 1 inch in diameter fell near Castle Rock and Thornton. Hail to 3/4 inch was measured near Northglenn and Fort Lupton.

In 2006…severe thunderstorms raked metro Denver. Hail as large as 2 1/2 inches in diameter shattered automobile windshields in and near Boulder. Hail to 1 3/4 inches pounded areas in and near Lakewood and Morrison. Hail to 1 inch was measured in Wheat Ridge along with 7/8 inch hail in Arvada. Severe thunderstorm wind gusts estimated to 69 mph snapped power lines for a distance of one quarter mile near Castle Rock. Severe thunderstorm winds were measured to 60 mph in Sedalia. Hail as large as 1 inch in diameter fell near Evergreen and Castle Rock. Hail to 3/4 inch in diameter was reported in Louviers and near Conifer.

In 2015…two colliding outflow boundaries merged over east Denver and northwest Aurora at the height of rush hour. The collision quickly spawned a severe thunderstorm that produced an EF1 tornado…damaging hail…torrential rain and flash flooding. The tornado touched down in east Denver and west Aurora. The tornado first touched down near Quebec and 6th Avenue. It then moved east northeast across the Lowry Campus into the west part of Aurora. The tornado then lifted near Mount Nebo Memorial Park. Some homes had minor roof damage with one former apartment building on the Lowry Campus had more significant roof damage. The tornado and intense thunderstorm winds uprooted trees…damaging vehicles and blocking roads. The storm produced torrential rain…2.0 to 2.5 inches…much of which fell in less than 30 minutes and resulted in flooded intersections and power outages. Flash flooding forced the evacuation of a theater at the Cherry Creek Shopping Center…where drifts of hail formed in the parking lot…and flooding set off alarms at the University of Denver`s Ritchie Center. Numerous water rescues were reported as vehicles stalled flooded intersections. Many stoplights were knocked out. The water was reportedly 3 feet deep on the South Broadway ramp to Interstate 25. The bike path along Cherry Creek was inundated with several feet of water at the height of the storm. Ironically…it was “Bike to Work Day”…which made for a long commute home for many. The South Platte River crested above flood stage for one hour. Employees still at work were urged to stay inside but others waded across flooded intersections downtown. About 30 flights had to be diverted from Denver International Airport. At Denver International Airport… only 0.05 inches of rain fell. A peak wind gust to 47 mph was observed from the southeast.