National Weather

CSU teams forecasts above average hurricane season

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CSU 2010 hurricane forecast
Hurricane forecasters at CSU predict unusually high levels of hurricane activity in 2010.

The hurricane forecasting team at Colorado State University released an updated forecast for the 2010 season and they continue to predict an above normal level of activity. The numbers would seem to put residents along the Atlantic and Gulf Coasts on notice that they should be prepared.

The CSU team’s forecast, generated by Dr. Phil Klotzbach and Dr. Bill Gray, portend what may be an active season in the Atlantic basin.

The team is calling for 15 named storms, 8 hurricanes and 4 major hurricanes (Category 3 or higher). By contrast, an average season has only 10 named storms, 6 hurricanes and 3 major hurricanes.

Residents in coastal regions will want to take note that the forecasters said there is a 69% probability of a major hurricane striking the United States coastline. That is 17% above the average for the past century.

Breaking their analysis down further, Klotzbach and Gray forecast a 45% chance of a major hurricane striking the U.S. East Coast and a 44% chance of one striking the Gulf Coast. For the Caribbean, a 58% chance of a major hurricane tracking through the area is given. Each of those reflects significant increases above average.

This year the team says weakening El Nino conditions coupled with warmer water in the Atlantic will account for considerably above normal activity. The 2009 hurricane season fell flat and finished with the fewest number of storms since 1997 and was one of the least active on record.

AccuWeather.com’s hurricane forecasting team led by Joe Bastardi issued their forecast last month and predicted an ‘extreme season.’ Their forecast called for 16 to 18 named storms with two to three with five hurricanes making landfall, two to three of those being major hurricanes.

Hurricane season officially starts on June 1st and runs through November 30th. However, hurricanes can and have formed anytime between March and December.

For more on hurricanes, check out these other stories from the Natural Disasters Examiner:

Climatology, Thornton Weather

Denver’s March was warmer, drier than average

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Denver's March 2010 snowstorm
Despite the snowstorm that struck on March 23rd and 24th and the rain that fell beforehand, the National Weather Service says Denver's March precipitation was below normal.

According to the Denver / Boulder office of the National Weather Service, Denver’s March weather was warmer and drier than normal. The latest climate summary from the service would seem to contradict what Denver residents actually experienced, at least in terms of precipitation.

The report starts with a seemingly contradictory statement saying, “Denver’s March 2010 finished with below normal liquid moisture in spite of finishing above normal in the snowfall category.”

According to the report, Denver recorded 0.80 inch of precipitation, well below the normal of 1.28 inches. Most of that occurred in conjunction with the snowstorm on the 23rd of the month when the official measuring station at Denver International Airport (DIA) reported 0.61 inch of precipitation.  By contrast, ThorntonWeather.com recorded 1.42 inches of precipitation from that storm alone and 1.90 inches for the month. 

March is Denver’s snowiest month recording on average 11.7 inches of snow. This year the month yielded 12.8 inches, most of which fell during the snowstorm that struck from the 23rd to the 24th. The service noted that this was the third month this snow season with above normal snowfall.  We recorded more snow here in Thornton with 15.3 inches. 

Overall for the season, Denver has recorded 58.8 inches of snow which is 7.5 inches above the average snowfall up to this point. Denver’s snow season runs from July through June and we average 61.7 inches over that period so for 2010 we are quickly approaching a ‘normal’ year.

The average temperature as recorded at DIA was 41.0 degrees which was 1.4 degrees above the normal of 39.6 degrees. Temperatures for the month ranged from a high of 82 degrees on the 30th down to a low of 13 degrees on the 20th. The 82 degree high temperature on the 30th broke the record for that date of 81 degrees set way back in 1879.

Controversy once again surrounds measurements in latest report

Questions have been raised numerous times about how the move of Denver’s official monitoring station to DIA has skewed the climate records for the city. Evidence shows that the 14 mile move has forever altered Denver’s records.

The March 2010 climate summary once again highlights the problem. Comparison of temperature records for DIA versus areas closer to historical monitoring locations continue to show discrepancies. Standing out even more are precipitation records that are curious at best, ridiculous at worst given the wet snowstorm that struck on the 23rd and 24th.

The Denver Weather Examiner is in the process of updating our previous investigation and will have an updated report soon. In the meantime, you may wish to look at the results of the investigation we conducted last year.

Weather History

April 4 to April 10 – This week in Denver weather history

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April 4 through April 10 - This week in Denver weather history
April 4 through April 10 - This week in Denver weather history

As we discussed in our April preview, the month is Denver’s third snowiest month behind March and November.  Our look back in Denver weather history for this week clearly shows that the month can bring not only snow, but lots of it.  If we look just at the last decade or so, we see significant snowstorms occurring in 1997, 2001, 2004 and 2005.  Will that happen this year?  Also notable are damaging wind events including one in 1999 that caused $20 million in damage.

31-4

In 1905…much rain and some snow occurred over the 5 days behind an apparent cold front.  Precipitation totaled 2.00 inches.  There was a thunderstorm on the 3rd.  Snowfall totaled 3.0 inches on the 4th.  North winds were sustained to 34 mph on the 1st and 2nd and to 30 mph on the 3rd. High temperatures during the period ranged from the upper 30’s to the lower 40’s.  Low temperatures were in the upper 20’s and lower 30’s.

2-4  

In 1934…snowfall totaled 8.2 inches in downtown Denver from the afternoon of the 2nd through the early morning of the 4th.  Most of the snow…6.8 inches…fell on the 3rd. Rain changed to snow behind a strong cold front on the afternoon of the 2nd.  The cold front first appeared as a long-cigar shaped squall cloud to the north of the city. Strong north winds at sustained speeds of 33 mph with gusts to 43 mph produced much blowing dust and an abrupt fall in temperature…from a high of 68 on the 2nd to a low of 22 on the 3rd.
 
In 1964…a major storm dumped 10.9 inches of heavy wet snow on Stapleton International Airport where northeast winds gusted to 35 mph.  Most of the snow…10.0 inches…fell on the 3rd.

2-5

In 1918…snowfall totaled 12.4 inches over downtown Denver. Most of the snow fell on the 3rd and 4th.  Temperatures were in the 20’s and 30’s.  Northwest winds were sustained to 24 mph on the 2nd.

3-5

In 1996…the foothills west of Denver received 6 to 8 inches of new snow.  Only 0.8 inch of snow fell at the site of the former Stapleton International Airport…along with some freezing drizzle on the 4th and 5th.  North-northeast winds gusted to 30 mph at Denver International Airport on the 3rd.

3-6

In 1898…snowfall totaled 8.7 inches in downtown Denver over the 4 days.  Northeast winds were sustained to 48 mph with gusts as high as 60 mph on the 3rd.
 
In 1983…a prolonged heavy snow storm blanketed the area along with very cold temperatures.  The greatest amounts of snow fell in the foothills where 24 to 42 inches were measured.  A foot of snow fell in Boulder.  Snow fell for 50 consecutive hours at Stapleton International Airport on the 3rd through the 5th with a total snowfall of 8.8 inches and a maximum accumulation on the ground of 6 inches on the 5th.  In Denver…the mercury failed to rise above freezing for 3 consecutive days…on the 4th…5th…and 6th…for the first time ever in April.  Five daily temperature records were set from the 4th through the 6th. Record low temperatures of 12 degrees occurred on the 5th with 7 degrees on the 6th.  Record low maximum temperatures of 25 degrees occurred on the 4th…27 degrees on the 5th… And 28 degrees on the 6th.

4

In 1888…southwest winds were sustained to 40 mph.
 
In 1915…Chinook winds from the northwest were sustained to 40 mph with gusts to 43 mph.  The winds warmed the temperature from a low of 44 degrees to a high of 67 degrees.
 
In 1935…light dust enveloped the city during the day on southwest winds sustained to 23 mph with gusts to 27 mph.
 
In 1985…north winds gusted to 53 mph at Stapleton International Airport where the visibility was briefly reduced to less than a mile by blowing dust and a snow shower.
 
In 1987…microburst winds gusted to 51 mph at Stapleton International Airport.
 
In 1997…heavy snow developed over western portions of metro Denver and along the palmer divide.  As a strong surface low pressure system intensified over the plains…moist upslope flow developed across metro Denver producing strong north winds at 20 to 40 mph and some blowing snow. Snowfall totaled 12 inches at Conifer with 4 to 7 inches at Crow Hill…Evergreen…and Morrison.  Thunderstorm rain changed to snow across the city with 2.0 inches of snowfall measured at the site of the former Stapleton International Airport where precipitation (rain and melted snow) totaled 0.70 inch.  North-northwest winds gusted to 43 mph at Denver International Airport.

Continue reading April 4 to April 10 – This week in Denver weather history →

Thornton Weather

Dry and windy conditions prompt Red Flag Warning for the Front Range

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Weather warnings for April 3, 2010.
Thornton and the Front Range are under a Red Flag Warning until 8:00pm Saturday.

Thornton, the Front Range and most of southeastern Colorado are under a Red Flag Warning through 8:00pm tonight. The snow last week is a distant memory and winds and warm temperatures have created very dry conditions.

Winds have been increasing throughout the day and will continue to do so for the next few hours before they gradually ease. Humidities are exceptionally low, below 20% in many areas, and temperatures remain mild. These conditions have dried ground fuels and create a potentially hazardous situation.

Remember, a Red Flag Warning means that critical fire weather conditions are occurring or imminent. The National Weather Service said the warning will remain in place until 8:00pm this evening.

Grassfires are not uncommon this time of year and if they get started they can quickly spread thanks to the gusty winds. It was 47 years ago yesterday that winds helped to quickly burn 25,000 of land in southern Weld County near Roggen.

Climatology

April weather in Denver – A bit of everything for everyone

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Denver's April weather previewApril marks a transition between winter and summer for most of the country but for Denver it is especially true as we can see a stunning variety of weather. The proverbial April showers are certainly a possibility for Denver. Snow? Tornadoes? Thunderstorms? You bet – all can happen! For good measure throw in a chance for hail and even dust storms and April gives every type of weather condition you could like – or hate.

The good news is that sunshine and warmer temperatures are usually in abundance as the normal highs during the month move up from 57 degrees on the first to 65 degrees on the 30th. It is not unusual to have a number of days well into the 70’s and the low 80’s. We also see the normal lows move above freezing from 30 degrees at the start of the month to 39 degrees by the end. Temperature extremes can hit both ends of the spectrum with a record low of 2 degrees below zero on April 2, 1975 and a record high of 90 degrees on April 30, 1992.

Get the complete details on Denver’s April weather here in our April weather preview.

National Weather

Record setting rain in New England causes widespread flooding

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Many rivers were experiencing major (purple) or moderate (red) flooding according to the National Weather Service. (NWS / AHPS)
Many rivers were experiencing major (purple) or moderate (red) flooding according to the National Weather Service. (NWS / AHPS) Click the image for a slideshow of the flooding.

Record breaking rains across the Northeast turned into flooding the likes of which haven’t been seen in the region for more than 100 years. As hundreds of residents were forced to evacuate yesterday, authorities have warned that the worst is yet to come.

Earlier this month many of the same areas were struck by flooding but that event pales in comparison. Rainfall amounts have been staggering in Connecticut, Massachusetts, and New Hampshire. From New York to Maine, widespread flooding is expected.

The nation’s smallest state, Rhode Island, has suffered the most with rainfall in some areas approaching 10 inches. 120 homes in Cranston were evacuated and in Warwick 300 apartments and 100 businesses fled the rising floodwaters.

Interstate 95, the main route between Boston and New York was closed and may remain so for days. Amtrak was forced to cancel some train service through the region due to water on its tracks.

Rhode Island Gov. Don Carcieri said, “None of us alive have seen the flooding that we are experiencing now or going to experience. This is unprecedented in our state’s history.”
The governor gave all non-essential state personnel the day off and officials asked schools and businesses to consider closing as well.

The Pawtuxet River crested early Wednesday in Cranston at 20.79 feet – more than 10 feet above flood level and almost six feet above the record level.

Other rivers in the region were already above flood stage and some may not crest for days leading officials to warn that the worst is yet to come. The Charles River in Dover, Massachusetts and Merrimack Basin tributaries in New Hampshire and Massachusetts were at ‘major flood stage’ according to NOAA’s Advanced Hydrologic Prediction Service.

State of emergencies were declared in Rhode Island, Connecticut and Massachusetts and governors in those states called out the National Guard to help with relief and recovery efforts.

President Barack Obama had already declared Major Disasters for Maine, New Hampshire, Rhode Island and Massachusetts from the flooding earlier this month.

Climate Change

British Parliament investigation into Climategate largely clears scientists

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A British Parliament committee has largely absolved scientists involved in the Climategate email scandal but also accused them of a 'culture of withholding information.' (Examiner.com)
A British Parliament committee has largely absolved scientists involved in the Climategate email scandal but also accused them of a 'culture of withholding information.' (Examiner.com)

A formal inquiry by the British Parliament’s Science and Technology Committee into the Climategate email scandal has largely absolved the British scientists involved of the most serious allegations against them. The panel did however also conclude that there were issues that needed to be addressed in order to allay public doubts about the scientists’ work.

The panel took a cursory look into the accusations that have been leveled against the University Of East Anglia (UAE), its Climate Research Unit (CRU) and the head of CRU, Dr. Phil Jones. Only one day of hearings were held in the inquiry that was first announced in January. 

Among the issues the committee discussed were the charges of manipulation / suppression of data, UAE’s / CRU’s practices for information dissemination and its compliance with Freedom of Information Act (FOIA) requests.

In a 63 page report (link above), the British MP’s outline the case against those involved and the conclusions they reached. For most critical issues including the charges of data manipulation that were brought about by emails discussing a ‘trick’ to ‘hide the decline’, the panel concluded Jones and his colleagues had not done anything untoward.

It further concluded that the climate data generated by CRU is in line with other datasets from NASA’s Goddard Institute of Space Studies (GISS) and the National Climatic Data Center (NCDC). “We therefore conclude that there is independent verification, through the use of other methodologies and other sources of data, of the results and conclusions of the Climate Research Unit at the University of East Anglia,” the report said.

A statement accompanying the report, the panel said that, “The focus on Professor Jones and CRU has been largely misplaced.” It notes that Jones’ limiting of access to the underlying data of his conclusions about manmade climate change were ‘standard practice’ in climate science.

However, all was not perfect in the report at the panel slammed the scientists and university for their lack of action on Freedom of Information Act requests.  Get all the details at the Climate Change Examiner.

Colorado Weather, Thornton Weather

Denver sets new record high temperature for March 30th

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Denver set a new high temperature record for today, breaking a 131 year old record.
Denver set a new high temperature record for today, breaking a 131 year old record.

Following on last week’s wintry blast, residents of the Mile High City were anxious for spring-like weather and they received it today. Denver has officially set a new record high temperature for the date breaking a 131 year old record.

The National Weather Service reported that at 3:32pm the mercury reached 82 degrees at the official measuring station at Denver International Airport (DIA). This breaks the previous record of 81 degrees set in 1879. The service noted that Rutherford B. Hayes was our 19th president at the time.

Here at ThorntonWeather.com, we reached a high of 81.7 degrees at 4:01pm.

Denver’s newest National Weather Service station at Denver City Park recorded a high temperature today of 81 degrees. Many believe this station is the one that should be the official reporting station for the city as the station at DIA has been shown to be skewing Denver’s climate records.

Other area stations reported similarly warm temperatures. Longmont reached a high temperature of 83 degrees breaking its old record of 81 degrees set in 1986. On the Rocky Mountain Weather Network,  Arvada reached 84 degrees, north Denver 83 degrees, Littleton 81 degrees and Broomfield 83 degrees.

National Weather

NASA satellite time lapse video shows February blizzards striking the northeast

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As seen from space, snow covers the Mid-Atlantic from Washington D.C. through Baltimore and Philadelphia to New York City. (NASA) Watch the amazing time lapse video below.
As seen from space, snow covers the Mid-Atlantic from Washington D.C. through Baltimore and Philadelphia to New York City. (NASA) Watch the amazing time lapse video below.

The northeastern United States has seen a winter of historical proportions as a seemingly endless stream of storms brought record setting levels of snowfall. NASA’s Geostationary Operational Environmental Satellite (GOES) captured a series of these storms as they struck in February.

The amazing time lapse video released by NASA covers the period from February 1st to February 16th. During that time, Philadelphia, Baltimore and Washington D.C. all saw major winter snowstorms that ranked in each city’s ‘top 10’ and gave way to terms like ‘Snowmageddon’ and ‘Snowpocalypse.’

Baltimore recorded an astounding 24.8 inches from February 5th to the 6th and 19.5 inches from February 10th to the 11th. The nation’s capital received 17.8 inches of snow during the February 5th / 6th snowstorm. The City of Brotherly Love was similarly buried under 28.5 inches from February 5th to the 6th and 15.8 inches from February 10th to the 11th.

The February storms added to already hefty seasonal snowfall totals across the northeastern United States that actually got a start in December. Baltimore, Washington D.C., Philadelphia, Wilmington, and Atlantic City have all seen seasonal snowfall records.

In a statement accompanying the video which compressed 16 days into two minutes, NASA explains these “Nor’easters”. “The counter-clockwise circulation around a low pressure system on the Atlantic coast pushes moist sea air from the north-east into arctic air over the land. This windy mixture creates a very efficient snow-making machine from Boston to Washington,” the agency said.

Weather History

March 28 to April 3 – This week in Denver weather history

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March 28 to April 3 - This week in Denver weather history
March 28 to April 3 - This week in Denver weather history

Looking at historical weather records can oftentimes provide insight into what weather we can expect over a given period of time.  As we saw this past week, while the calendar says spring, Old Man Winter can return very quickly.  Our look at this week in Denver weather history we see much of the same – major snowstorms and blizzards that impact travel and knock out power to residents.  Also, these spring snowstorms are often moisture-laden and their sheer weight can be damaging. 

27-28

In 1951…heavy snowfall totaled 6.5 inches at Stapleton Airport where north winds gusted to 38 mph on the 27th and 41 mph on the 28th.
 
In 1972…heavy snowfall of 6.2 inches was measured at Stapleton International Airport…where northeast winds gusted to only 21 mph.
 
In 1980…a major blizzard struck the northeastern Colorado plains…closing both I-70 and I-76 to the east of Denver for a time.  Some areas received 1 to 2 feet of snow.  Drifts were 4 to 8 feet high.  The storm killed many young livestock.  At Stapleton International Airport…snowfall totaled 6.7 inches from the storm and north winds gusted to 29 mph.
 
In 2002…high winds developed in the foothills west of metro Denver.  Winds gusted to 81 mph near Fritz Peak…72 mph at Rollinsville…and 70 mph at Blackhawk.  West winds gusted to 51 mph on the 27th and to 45 mph on the 28th at Denver International Airport where the temperature warmed to a high of 69 degrees on the 28th.

27-29

In 1948…high winds raked Boulder.  A wind gust to 75 mph was recorded at Valmont.  Sustained winds in excess of 35 mph were estimated in Boulder.  Minor damage was reported.
 
In 1961…heavy snowfall totaled 9.5 inches at Stapleton Airport over the 3 day period.  Most of the snow…5.3 inches…fell on the 28th.  Winds were generally light and gusted to only 22 mph from the north.

28   

In 1886…the lowest recorded temperature in March…11 degrees below zero…occurred.
 
In 1911…a thunderstorm produced snowfall of 0.4 inch…which was the only measurable snowfall of the month…making the month the second least snowiest March on record.
 
In 1962…a vigorous cold front produced strong winds across eastern Colorado.  North winds gusted to 46 mph at Stapleton Airport where visibility was briefly reduced to 3/4 mile in blowing dust.  A construction worker was injured in Aurora when he was struck by a windblown piece of plywood.

28-29

In 1891…rain changed to snow and totaled 9.7 inches in the city.  Northeast winds were sustained to 12 mph with gusts to 28 mph on the 28th.
 
In 1910…a strong cold front brought much wind…rain…and snow to the city.  Rain on the 28th changed to snow early on the 29th.  Snowfall totaled only 2.8 inches…but north winds were sustained to 50 mph on the 29th. Precipitation from the storm totaled 0.96 inch.
 
In 1994…moist upslope winds combined with an upper level system to dump 5 to 7 inches of snow along the eastern foothills and across metro Denver.  Snowfall totaled 6.3 inches at Stapleton International Airport where northeast winds gusted to 39 mph.  Thirteen inches of new snow were measured at the Eldora Ski Area west of Boulder.

Continue reading March 28 to April 3 – This week in Denver weather history →

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