Category Archives: Thornton Weather

Thornton’s June weather preview – Severe weather arrives in Colorado

June typically brings severe weather to Thornton and the Denver area.
June typically brings severe weather to Thornton and the Denver area.

June is historically Denver’s severe weather month and severe thunderstorms, tornadoes and hail are notorious visitors to Denver and across eastern Colorado during the month.  In fact, over 40 percent of the tornadoes that occur in Colorado are observed in June and these are typically the most destructive of the year.  Severe thunderstorms have also caused major property damage across the Front Range during the month.

In just the last 25 years or so, there have been some particularly notable storms in June.  Tornadoes have struck the metro area including one that longtime Thornton residents will recall on June 3, 1981.  53 residents were injured, 25 homes were destroyed and 239 other structures were damaged.  Others tornadoes in the metro area include southeast Denver and Aurora on June 8, 1986 and east Denver on June 13, 1984.  Severe thunderstorms occurring on June 13, 1984 dumped large hail making it one of the worst and the second costliest storm in Denver history.  More recently, on June 20, 2001, a major hail storm moved across Denver International Airport dropping hailstones as big as two inches in diameter. Damage was extensive on and near the airport.

Read more about Thornton and Denver’s June weather including a look back at last year’s stormy June and a look ahead at this year.

Hail and tornadoes make for eventful Wednesday afternoon

Hail covers the road at 104th Avenue and Chambers Road on Wednesday afternoon. (Chelsea Kovach)
Hail covers the road at 104th Avenue and Chambers Road on Wednesday afternoon. (Chelsea Kovach)

Colorado’s severe weather season is upon us and it paid a visit to the north Denver metro area in spades on Wednesday. Brief, heavy rain, large hail and a few tornadoes were reported with the fast moving storms.

Isolated thunderstorms began popping up along the Front Range after lunchtime, quickly turning severe in nature.

Hail nearly three inches in diameter pounded vehicles and homes in north Denver, Commerce City, Thornton and unincorporated Adams County. Enough hail fell in the Reunion development area of Commerce City to cover the ground like snow. Residents used snow blowers and state highway crews used snowplows to clear the frozen water.

An untold number of vehicles sustained heavy damage in the area northeast of downtown Denver. Reports of broken windows, roofs with damage and trees stripped of leaves were commonplace.  In the central part of Thornton there were reports of hail up to 1.75 inches in diameter.

Operations at Denver International Airport were affected as flights were delayed while the severe weather passed. Delays of 30 to 60 minutes were experienced and those inside the airport were instructed to go to designated tornado shelters for a time.

Brief, weak tornadoes were reported in some areas and strong winds caused damage further northeast of the area. In Larimer County, multiple structures were reportedly destroyed and a 15 foot silo was knocked down.

The severe weather was enough to draw the attention of the VORTEX 2 tornado study. The research study is the largest field study of tornadoes with hundreds of scientists and dozens of vehicles roaming the plains to learn more about the severe weather. The teams tracked the storms as they moved from near DIA to the plains further to the northeast.

Are you ready for severe weather?  Do you know what to do to keep you and your family safe? Review our Severe Weather 101 series to learn more:

Announcing our new advanced mobile ThorntonWeather.com site

ThorntonWeather.com now brings local, Thornton weather to your advanced mobile phone.
ThorntonWeather.com now brings local, Thornton weather to your advanced mobile phone.

With the advent of new advanced mobile phones like the Droid and iPhone, users of these devices are able to view more complete content than ever before.  No longer are they limited to totally stripped down versions of web pages.  Recognizing the proliferation of these new devices, ThorntonWeather.com has completely revamped our mobile website to provide users of advanced mobile devices a more interactive, graphical experience.

On ThorntonWeather.com Mobile (http://m.thorntonweather.com) you will find a familiar looking ‘dashboard’ much like on our full site.  It provides real-time Thornton weather conditions as well as an almanac with sunrise and sunset times, moon rise and moon set times, as well as the moon phases.

The forecast page has your complete local, Thornton forecast – not a forecast for DIA or downtown.  Radar is of course available including a local, regional and national view.  You can also view our weather webcams on the webcams page and graphs of today’s weather as well as days past.

Looking for some reading material?  Our news and blog section now has a mobile version as well which you can access from the mobile pages.  All of our recent news stories are available for viewing by mobile users.

You can access the mobile site by clicking the “Mobile” button on the top right of our main site or direct your phone’s mobile browser to http://m.thorntonweather.com.  Be sure to bookmark it so you can come back to it easily.

If you have any questions, comments or suggestions, please feel free to contact us.

Tornado Watch issued for all of eastern Colorado including Thornton

A Tornado Watch is in effect for eastern Colorado through 9:00pm Tuesday night. (NWS)
A Tornado Watch is in effect for eastern Colorado through 9:00pm Tuesday night. (NWS)

Update, 7:10pm – Most of the ‘action’ has shifted north of the metro area into Weld County. Multiple tornadoes have been spotted. Residents of Greely, Lockbuie, Fort Morgan and surrounding areas need to be aware of these severe weather conditions.

For the metro area, things have settled down a bit. However, a Tornado Watch remains in effect until 9:00pm. There remains a chance of an isolated thunderstorm moving off the foothills with severe wind, rain, hail and possibly tornadoes.

Have pictures of the severe weather? Email them to info@thorntonweather.com and we will post them!

Be sure to follow us on Twitter or ‘like’ us on Facebook for all the latest!

You can monitor the weather situation closely with these pages on ThorntonWeather.com:

Update, 5:05pm – The Severe Thunderstorm Warning that covered parts of the metro area has expired. However, a Tornado Watch remains in effect until 9:00pm for all of eastern Colorado including Denver.

Thus far the Front Range has been spared any tornadoes but there has been activity elsewhere in the state. One tornado was reported two miles east of Rockport in Weld County and another one mile east of the rest area near the Wyoming border, also in Weld County. No damage has been reported.

Update, 4:10pm – The National Weather Service has issued a Severe Thunderstorm Warning for western Adams, northeastern Denver and south central Weld County.  Radar indicates a severe thunderstorm that could produce one inch diameter hail over northern Denver and moving north at 25 mph.

Areas under this warning include Lochbuie, Brighton, Denver International Airport, northeastern Denver, eastern Thornton, Commerce City and northwestern Aurora.  The warning will remain in effect until 4:45pm.

If severe weather approaches your area, go inside to sturdy shelter and stay away form flood-prone areas.  Remember that a severe thunderstorm can produce damaging hail, winds in excess of 58 mph, deadly lightning and heavy rain. 

The Tornado Watch that covers all of eastern Colorado continues until 9:00pm.

Original story, 1:20pm: The stage is set for the first significant severe weather threat of the season to the Mile High City. Thunderstorms have quickly built as they moved off the foothills south of Denver and they are expected to increase in intensity as the afternoon progresses.

The National Weather Service has issued a Tornado Watch for all of eastern Colorado through 9:00pm tonight. This includes the Denver metro area and the entire Front Range.

Remember that a Tornado Watch means that conditions are favorable for tornadoes and severe thunderstorms. Residents in the areas under the watch should take appropriate precautions and stay tuned to media outlets for updates to the rapidly worsening conditions.

The biggest threat from these storms will be hail, damaging wind, dangerous lightning and tornadoes. The main area of focus for the worst of this is going to be over the Palmer Divide and areas east. However, it is entirely possible that more widespread severe weather will occur, including over the main part of the Denver area.

We will be updating this page throughout the afternoon and evening as long as the severe weather threat remains.

City of Thornton raises severe weather awareness with new brochure

The City of Thornton has created a new flyer for residents with basic severe weather information. (City of Thornton)
The City of Thornton has created a new flyer for residents with basic severe weather information. (City of Thornton)

Severe weather season is quickly going to arrive in Colorado – we have already seen signs of it in recent weeks.  Helping to bring attention to the dangers severe weather presents, the City of Thornton has created a new flyer with some tips for residents.

Available on the city’s website, the flyer covers the basics of tornado, thunderstorm and lightning safety.  It is a good, brief look at the highlights of keeping you and your family safe when severe weather strikes.

Click here to download and view the brochure (PDF)

For more in depth information on severe weather and safety, check out the links at the bottom of this story for our Severe Weather 101 series.

It is important to note that neither the City of Thornton or Adams County provide any sort of weather / civil alert system for residents.  Certainly for Thornton this is somewhat ironic considering the city is where the worst tornado to ever strike the metro area occurred

We discussed the issue with Thornton officials last year and will be approaching them again in the coming weeks to see if anything has changed since then.  Certainly after last year’s nasty summer weather, residents are on edge.

In the meantime, we cannot stress enough that city residents should have their own NOAA Weather Radio in their homes and businesses.  For more information about these crucial pieces of safety equipment, click here.

ThorntonWeather.com Severe Weather 101 Education Series

Breaking weather situation – Tornado watches and warnings posted

Live Thornton, Colorado weather image.
Live Thornton, Colorado weather image.

 Update, 5:15pm – The Tornado Watch for Adams County has been discontinued.  

We did see a number of tornadoes reported in Colorado so far today, mostly in the southeastern part of the start.  

In northeastern Colorado, two tornadoes were reported. One was reported at 3:28pm 9 miles southwest of Deer Trail in Elbert County. The second at 3:38pm two miles north of Leader in Adams County.

A very, very wet weather pattern will continue through Saturday and the chance for severe weather remains.  Be sure to stay tuned to ThorntonWeather.com! 

Update, 4:30pm: The Tornado Watch for Denver, Boulder, Broomfield and Jefferson Counties has been dropped. However, they remain in effect until 8:00pm for Adams, Arapahoe, Morgan, Washington, Weld, Elbert and Lincoln Counties. 

Two tornadoes have been reported so far. The first was at 3:28pm nine miles southwest of Deer Trail. The second was 10 minutes later at 3:38pm two miles west of Leader. No damage reports at this time. 

Original story, 3:30pm: Yesterday brought our first Severe Thunderstorm Warning of the season and today the situation gets more serious with Tornado Watches and Warnings being posted.  The severe weather threat looks to continue through the afternoon.  

A Tornado Watch has been issued for much of the Front Range including all of Adams, Arapahoe, Boulder, Broomfield, Denver, Douglas, Jefferson, Morgan, and Weld Counties.  This watch includes the entire Denver metro area including Thornton.   

Remember that a Tornado Watch means conditions are favorable for the development of severe thunderstorms producing tornadoes in and close to the watch area.   

Showers and thunderstorms are expected to continue to develop across the Front Range this afternoon and evening.  These are expected to include heavy rain, strong winds, hail and possibly hail.  Residents need to take immediate precautions to protect themselves.  

Remember, Thornton and Adams County do NOT have any type of weather warning system for residents – no sirens, text alerts, etc.  You should have your own NOAA weather radio or stay tuned to local media (and ThorntonWeather.com of course) for all the latest when severe weather strikes.  

Satellite imagery of Iceland volcano eruption

Satellite image of the Eyjafjallajokull volcano in Iceland erupting
NASA's Terra satellite flew over the volcano on April 16 10:45 UTC (6:45 a.m. EDT) and the MODIS instrument captured a visible image of Eyjafjallajökull's ash plume (brown cloud) stretching from the U.K. (left) to Germany (right). (NASA/MODIS Rapid Response Team) Click on the image or on the link below to view a slideshow of satellite photos of the eruption.

Satellites by space agencies across the globe have trained their ‘eyes in the sky’ on Iceland and the erupting Eyjafjallajokull volcano. From their perch hundreds of miles above the Earth’s surface, these satellites can capture images of the volcano and its ash plume as it travels across northern and central Europe.

The ash cloud has now traveled hundreds of miles over northern Europe where it has created the biggest travel disruptions since the September 11th terrorist attacks. Thousands of flights have been cancelled and hundreds of thousands of passengers have been stranded across the world.

At Denver International Airport, United Airlines and British Airways cancelled their non-stop service to and from London’s Heathrow airport Saturday. This marks the third day in a row for the disruption.

The volcanoes activity increased overnight and continues on Saturday. Eurocontrol, the European agency responsible for air travel over the continent, reports that 16,000 flights had been cancelled on Saturday. On a normal Saturday the organization would monitor 22,000 flights.

Satellite images in the slideshow below from NASA, the European Space Agency (ESA) and others provide an incredible look into the event.    

Image of Iceland's Eyjafjallajokull volcano

Statewide tornado drill to occur in Colorado on Wednesday

This funnel cloud was seen from the Thornton Civic Center (looking north) on June 10, 2009. Image courtesy Lisa Wilson, the City of Thornton.

If you happen to be outside or listening to broadcast media this morning, don’t be surprised to hear a tornado warning / siren. As part of Severe Weather Awareness Week, the National Weather Service will be conducting a statewide tornado test around 9:15am.

The service is urging all government agencies, schools, businesses, broadcast media and emergency management agencies to participate in this important drill.

This is a good time for citizens to ensure they are prepared and know what to do when a tornado strikes. As we saw with last year’s tornado activity and in 2008 with the Windsor tornado, twisters can and do strike the Denver area. Preparation and planning are critical to ensuring you and your family remain safe.

It is perhaps most fitting that Colorado saw its first tornado of 2010 yesterday. The twister which struck in Kit Carson County 11 miles south-southwest of Bethune caused no damage. However, it serves as an important reminder.

Will you hear tornado sirens in Thornton?  Unfortunately not.  The city does not have a warning system in place.  Find out why.

Do you know what to do when a tornado strikes?  Learn what you can do to protect you and your family here.

Denver’s March was warmer, drier than average

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.

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

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.