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UpdatedThu, 24-Apr-2014 2:20am MDT 
 

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Cancellations on Everest amid talks to save climbing season

Wednesday, April 23rd, 2014 6:28am MDT
Cancellations on Everest amid talks to save climbing season (via AFP)

Another major mountaineering company has abandoned its Everest expedition after a deadly avalanche killed 16 Nepalese guides, as the government strove Wednesday to save the climbing season, a vital earner for the country. New Zealand-based Adventure…


» Click here to read the rest of Cancellations on Everest amid talks to save climbing season
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Wednesday temperatures to be closer to normal, better chance for showers

Wednesday, April 23rd, 2014 6:05am MDT

Yesterday temperatures topped out about 16 degrees above normal.  A trough moving through Colorado today will bring those readings down closer to normal – but still a bit above average.  

Partly sunny skies will be the general rule with some increase in cloud cover this afternoon.  High temperatures will be topping out at about 67 degrees, a few above the average for today’s date of 63 degrees.  

This afternoon will bring gusty northwest winds and a slight chance for showers from about noon through much of the evening.  Right now we aren’t expecting much moisture out of these but some could bring a quick shot.  

See the image for today’s #Thornton#weather outlook and check out our home page for the latest.

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April 2014 top shots: Monthly photo slideshow

Wednesday, April 23rd, 2014 4:35am MDT
April 2014 started with blossoming trees. Scroll down for more photos from the month.  (LW Inactivist)

April 2014 started with blossoming trees. Scroll down for more photos from the month. (LW Inactivist)

April 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!

That stunning variety will undoubtedly be showcased in our monthly photo slideshow (below).

  • Slideshow updated April 23, 2014

Showcasing images captured by ThorntonWeather.com readers as well as some of our own, our monthly slideshow covers the entire gamut of weather-related imagery.  Sunsets, sunrises, wildlife and of course snow are vividly depicted.

Throughout the month we will gather the images sent to us via email or shared with us via our various social media outlets and post them in the slideshow below.

To learn more about getting your photos added to our monthly slideshow, click here. 

Click the play button below and sit back and enjoy the images.

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April 20 to April 26: This Week in Denver Weather History

Tuesday, April 22nd, 2014 7:15am MDT
This Week In Denver Weather History

April 20 to April 26: This Week in Denver Weather History

Pick your poison. Blizzards and monster snow? Torndoes? Hail? Deadly lightning? All of the above have been seen during this week in Denver’s past.

From the National Weather Service:

18-20

In 1966…sub-freezing temperatures caused thousands of dollars in damage to fruit trees across metro Denver. Minimum temperatures were in the teens each morning and failed to reach above freezing on the 19th. The low temperature of 13 on the 20th set a new record minimum for the date. Snowfall totaled 5.7 inches at Stapleton International Airport during the period.

19-20

In 1892…rain on the 18th changed to snow on the 19th and totaled 6.0 inches over downtown Denver into the 20th. Total precipitation was 1.56 inches. North winds were sustained to 26 mph on the 19th.

In 1907…a major storm dumped 18.0 inches of snowfall in downtown Denver. Much of the heavy wet snow melted as it fell. The most snow on the ground was 7.0 inches at 6:00 pm on the 19th. North to northeast winds were sustained to 42 mph on the 19th and to 21 mph on the 20th. High temperatures were in the low to mid 30′s with low readings around 20.

19-21

In 1984…a large snowstorm buried most of Colorado under a thick mantle of wet snow. Total snow amounts ranged from 10 to 20 inches across metro Denver and a whopping 20 to 40 inches in the adjacent foothills. The snow closed roads and damaged electrical transformers…causing numerous power outages. Nearly 14 inches (13.6) of snow fell at Stapleton International Airport where the combination of snow and wind closed all but one runway…resulting in the cancellation of many flights. Both I-70 and I-76 were closed to the east of Denver.

19-22

In 1933…a major storm dumped 16.8 inches of snowfall over downtown Denver when rain changed to snow during the early morning of the 20th and continued through midday of the 22nd. Most of the snow fell on the 21st. Due to melting… The most snow on the ground was 10.5 inches at 6:00 pm on the 21st. Before the snow started…a strong cold front on the evening of the 19th produced north winds sustained to 35 mph with gusts to 37 mph. The strong winds deposited a thin layer of dust on the city. North to northwest winds were sustained to 31 mph with gusts to 35 mph on the 20th and to 29 mph with gusts to 32 mph on the 21st.

20

In 1874…light snow fell for most of the day…but melted almost as fast as it fell. The flakes…as large as 1 1/2 inches in diameter during the afternoon…resembled white feathers. Precipitation from melted snow was only 0.21 inch in the city. Snowfall was much heavier in the mountain parks where snow depths were reported between 3 and 5 feet from the storms of the 15th and 20th. The heavy snow resulted in the deaths of hundreds of cattle and sheep.

In 1875…the city was enveloped in a severe wind and sand storm. For nearly 30 minutes before the storm…it could be seen moving toward the city from the northwest as a black wall of clouds extending only 10 degrees above the horizon. At 5:30 pm…the sand was sweeping past in such clouds that objects at a distance of only 10 yards were not visible. The streets were entirely deserted. The greatest velocity of wind during the storm was 36 mph from the north-northwest. The storm diminished by 7:00 pm. Swarms of grasshoppers were seen today and were reported in all parts of the territory.

In 1897…southwest winds were sustained to 46 mph with gusts to 50 mph. The apparent Chinook winds warmed the temperature to a high of 76 degrees.

In 1905…apparent post-frontal north winds were sustained to 43 mph.

In 1912…west winds were sustained to 42 mph with an extreme velocity of 48 mph.

In 1958…strong Chinook winds gusted to 52 mph at Stapleton Airport.

In 1981…3/4 inch hail fell in Lakewood with up to one half inch of rain in a few minutes across northern sections of the city of Denver. Thunderstorm rainfall totaled 0.39 inches at Stapleton International Airport…where 1/4 inch hail was also measured.

In 1987…6 to 12 inches of heavy snow fell in the foothills. Only 2.5 inches of snow fell at Stapleton International Airport where the usual flight delays occurred.

In 2005…severe thunderstorms produced large hail across metro Denver. Hail as large as 1 3/4 inches in diameter fell at Denver International Airport. Hail to 3/4 inch in diameter fell in and near Golden and near Hudson… Keenesburg…Barr Lake…and Bennett.

In 2013…an avalanche pushed a group of six snow boarders into the Sheep Creek Gully of Loveland pass. This is near but outside the Loveland Ski Area boundary. Five of the six members of the group died as they were completely buried. The avalanche is the deadliest in Colorado since 1962 when seven people were killed when a slide buried residents at twin lakes near independence pass.

20-22

In 1957…strong and gusty south to southeast winds raked metro Denver each day. The strongest wind gust of 55 mph occurred on the 21st when blowing dust briefly reduced the visibility to 3/4 mile at Stapleton Airport.

20-23

In 1989…unusually warm weather resulted in several daily temperature records being broken in Denver. The high temperature of 89 degrees on the 21st exceeded the record maximum for the month at that time. Daily record high temperatures were either exceeded or equaled with 83 degrees on the 20th…88 degrees on the 22nd…and 85 degrees on the 23rd. The low temperature of 55 degrees on the 22nd equaled the record high minimum for the date.

21

In 1885…rain changed to snow during the early morning and was the heaviest snow of the season. Total snowfall was estimated at 8.0 inches over downtown Denver…but the snow melted rapidly on the ground as it fell. However… The weight of the snow…as well as northwest winds sustained to 29 mph downed telegraph and telephone wires. Several large branches of trees were also broken by the weight of the snow. Precipitation totaled 1.01 inches from the storm.

In 1887…west winds were sustained to 47 mph.

In 1932…the temperature dipped to a low of only 60 degrees… The all-time record high minimum for the month.

In 1988…a small tornado was observed by National Weather Service employees about 3 miles northwest of Thornton. It was on the ground for about 2 minutes. No damage was reported. Later…lightning struck two 14-year-old girls on a softball field in Westminster. One was killed…while the other suffered moderate injuries. Northwest winds gusted to 44 mph at Stapleton International Airport behind a cold front.

In 2010…severe thunderstorms produced large hail…strong winds and a tornado across parts of Adams…Arapahoe… Elbert…and weld counties. The hail…up to 1.50 inches in diameter…came down so heavy along parts of I-70 and I-76 that snowplows had to be called out to remove it. Numerous vehicles were damaged by hail. In weld County…very heavy rain and hail accompanied thunderstorm winds up to 75 mph. Hail up to 1.50 inches was reported near Bennett; 1.25 inches…5.3 miles east of Englewood; 1.0 inch size hail near Buckley Field; with 0.88 inch size hail near Boulder. A weak tornado touched down briefly in Elbert County…about 9 miles southwest of deer trail…but did no damage. Several minor accidents were reported with snowpacked and slick road conditions along with very low visibilities. Minor street flooding was reported in southeast Aurora. Denver International Airport recorded 0.30 inches of rainfall. Also…a peak wind gust to 36 mph from the southeast was observed at the airport.

21-22

In 1910…north winds were sustained to 45 mph behind a cold front. Rainfall totaled 0.63 inch.

In 1923…snowfall of 2.0 inches in the city was the only snow of the month and the last measurable snow of the season. Northwest winds were sustained to 25 mph on the 21st.

In 1952…heavy snowfall totaled 7.6 inches at Stapleton Airport. The storm was accompanied by north winds gusting to 33 mph.

In 2001…the second major snow storm in 11 days moved into metro Denver with blizzard conditions developing again across the plains to the northeast of Denver. Snowfall amounts ranged up to 9 inches in metro Denver with up to 23 inches in the foothills. Northwest winds were sustained at 20 to 30 mph with gusts as high as 36 mph at Denver International Airport which was again shut down for nearly an hour by power outages on the 22nd. The outages affected lighting in the concourses…train operations…de-icing and refueling operations…flight information displays…and security screenings. Navigational aids were also affected… Resulting in the cancellation of 58 arriving and departing flights which stranded about 5000 passengers. Across metro Denver storm totals included: 9 inches at Eldorado Springs; 7 inches in Boulder; 6 inches at Ken Caryl…Northglenn and near Sedalia; and 5 inches in Arvada and Morrison. Only 1.7 inches of snow were measured at the site of the former Stapleton International Airport. In the foothills snow totals included: 23 inches near Fritz Peak south of Rollinsville…17 inches near Jamestown…16 inches near Blackhawk…14 inches in Coal Creek Canyon…13 inches at Idaho Springs and near Nederland…11 inches at Aspen Springs…and 10 inches near Bergen Park.

» Click here to read the rest of April 20 to April 26: This Week in Denver Weather History

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Climbing temperatures, increased wind for Thornton on Tuesday

Tuesday, April 22nd, 2014 6:45am MDT

An unseasonably mild day is expected today as we will likely break the 80 degree mark for the second time of the year.  The warm temperatures however will also be accompanied by some gusty afternoon winds.

With mostly sunny skies above look for a high today right around 81 degrees or so.  Winds will be relatively calm in the morning then increasing in the afternoon.  By mid-afternoon gusts from 25 to 30 mph will be possible.  From then into the evening we have just the slightest chance to see isolated showers and thunderstorms.

See the image for today’s outlook and head tohttp://www.thorntonweather.com for all the latest.

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Thornton starts workweek with a seasonal Monday, more of the same ahead

Monday, April 21st, 2014 6:59am MDT

Following our pleasant, springtime Easter weekend, we can expect to see similar conditions through the week.

Monday starts things off with high temperatures right near the average for the date of 67 degrees.  Mostly sunny skies will be above with some breezy winds early.  A few isolated showers / thunderstorms will be possible this afternoon but right now it looks like that activity will be south and west of us.

Looking ahead, Tuesday should be the warmest day of the week with highs in the mid to upper 70s and another chance for thunderstorms.  Wednesday through Friday will see highs right around normal again with periods of breezy winds.

Saturday will be cooler and then, depending on how things play out, we could see snow on Sunday.

See the image for today’s Thornton weather outlook and get more details about the extended forecast here.

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Severe Weather 101 – Severe Weather Awareness Week wrap up

Saturday, April 19th, 2014 8:30am MDT
Supercell thunderstorms like this can be beautiful - but they can also be deadly.  Do you know what to do when severe weather strikes?  (Stormscape Photography / FLICKR)

Supercell thunderstorms like this can be beautiful – but they can also be deadly. Do you know what to do when severe weather strikes? (Stormscape Photography / FLICKR)

Over the past week we have highlighted some of the severe weather hazards that we face in Colorado every spring and summer in our Severe Weather 101 series.  The dangers these present are significant and not to be taken lightly.

Tornadoes grab most of the headlines and certainly are a danger however others like lightning and flooding are more common and actually claim more lives.  We ask all of our readers to please, take the time to review these important articles – they could save yours and your family’s lives!

The National Weather Service has published a nice wrap up of Severe Weather Awareness Week that covers all the basics – see it below.  For more in depth information, please use the links at the bottom to view each article on our Severe Weather 101 series.  Be safe and be weatherwise!

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
600 AM MDT SAT APR 19 2014

SEVERE WEATHER AWARENESS WEEK IN REVIEW

Severe Weather Awareness Week in review…

Severe Weather Awareness Week in Colorado concludes today. During the past week we have presented information and safety rules for tornadoes, lightning and wildfires, floods and flash floods, straight-line thunderstorm winds, hail, and our warning programs.

We will now review some of the most important safety rules in our effort to build a Weather-Ready Nation.

Be weather-wise by staying informed on expected weather in your area. The National Weather Service is typically aware of the potential for severe weather many hours or even days before any severe weather watches or warnings are issued, providing forecast products to heighten your awareness. A Weather Story product is posted each day on National Weather Service Internet pages and Facebook pages which includes a map and text on possible hazardous weather expected within the next seven days.

A Hazardous Weather Outlook is also issued daily with information on possible hazardous weather through the next seven days. A watch is issued when conditions for severe weather or flooding become possible. A warning is then issued when life threatening conditions are imminent or occurring.

Tornadoes

Tornadoes can even strike in mountain areas.  In 2008 on August 23rd, this rope tornado struck Park County near Eleven Mile Reservoir.  Image courtesy Jerry Bivens.

Tornadoes can even strike in mountain areas. In 2008 on August 23rd, this rope tornado struck Park County near Eleven Mile Reservoir. Image courtesy Jerry Bivens.

The best way to protect yourself from tornadoes is to have a plan of action. The safest place to be if a tornado approaches is in a basement or safe room within a well-built structure, or in an underground storm shelter. If none of these options are available, move to a hallway or a small interior room on the lowest floor, usually this is a closet or bathroom. Get under a heavy piece of furniture or in a bath tub and cover yourself with blankets. Remember, the greatest risk of injury from tornadoes is from flying debris.

Modular homes and mobile homes, even those tied down, offer little protection from tornadoes. If a tornado approaches, leave those locations and seek safety in a nearby sturdy building or storm shelter.

If you are driving in open country and see a tornado, if time permits, the best thing to do is simply drive away from the tornado path. Do not take shelter beneath a highway overpass. Wind speeds may actually be higher in these areas and often become collection points for debris.

If you are caught outside and cannot seek shelter inside a sturdy structure, crawl into a culvert or lie down in a narrow ditch or ravine and cover your head. But remember that the worst place to be when a tornado threatens is outside in the midst of flying debris.

Lightning

Since 1980, lightning has killed and injured more people in Colorado than any other thunderstorm hazard. Lightning also causes many wildfires.

The best defense to protect yourself against a lightning strike is to plan ahead and avoid being caught where you might be vulnerable. Check weather forecasts prior to venturing out, especially if you are heading into the mountains. Plan outdoor activities early in the day before storms develop.

If thunderstorms threaten, seek shelter in a building or in an enclosed metal-roof vehicle, making sure all windows and doors are closed. Never seek shelter under an isolated tree. During thunderstorms, stay off corded telephones, away from electrical devices, and away from plumbing. Also get out of shower stalls, bath tubs, swimming pools and lakes when lightning is nearby.

You should wait at least 30 minutes after the last sound of thunder before resuming outdoor activities. When thunder roars…go indoors.

Floods and Flash Floods

The Big Thompson Flood in 1976 claimed the lives of 144 Coloradoans and serves to remind us of the dangers of floods. (USGS)

The Big Thompson Flood in 1976 claimed the lives of 144 Coloradoans and serves to remind us of the dangers of floods. (USGS)

When flooding or flash flooding is possible, you should remain alert and be ready to quickly evacuate to higher ground or climb to safety. Flash floods often occur suddenly and without warning. You need to follow some basic flood safety rules:

Do not camp or park your vehicle along streams and washes, particularly during threatening conditions. If you are near a river, be aware of water levels and be prepared to move to higher ground if river levels rise. Do not enter areas that are already flooded. If walking or fishing along a river, be aware that erosion from swift running water can cause river banks to collapse. Never let your children play around high water, storm drains, viaducts or arroyos.

Nearly half of all flash flood fatalities are vehicle related. While driving your automobile, look out for flooding at highway dips, bridges and low areas. Two feet of moving water will carry away most vehicles. Never attempt to drive across a flooded road. And be especially cautious at night when it is difficult to see flood dangers.

Strong Straight-Line Winds

Straight-line winds from thunderstorms, including microbursts, can become quite strong, even reaching speeds in excess of 100 mph in extreme cases. When thunderstorms approach, high winds can suddenly develop, causing things on the ground to become swift moving airborne missiles with a potential force to injure or kill. As with any thunderstorm, seek shelter before the storm arrives.

Hail

This is one of the largest recorded hail stones which is more than 7 inches in diameter and fell in Nebraska in 2003.  (NOAA)

This is one of the largest recorded hail stones which is more than 7 inches in diameter and fell in Nebraska in 2003. (NOAA)

Large hail can pose a danger to animals and people. Hail also produces considerable damage to crops and personal property each year in Colorado. Again, get indoors before thunderstorms arrive. A fall of small hail can suddenly change to a fall of very large ice missiles which can injure or kill. Make efforts to protect personal property before storms threaten.

Warning Notification

When thunderstorms threaten, tune to NOAA All-Hazards Weather Radio, The Weather Channel, or your local radio or television stations. Also check the Internet web site from the National Weather Service office serving your area. And if you have a relatively new cell phone you should receive Tornado and Flash Flood Warnings on your phone if you are in the area of the warning.

During threatening weather days, plan the actions you will need to take so that you will be prepared if dangerous weather conditions actually develop.

NOAA’s National Weather Service wishes you a safe severe weather season.

Severe Weather Awareness Week in Colorado concludes today. During the past week we have presented information and safety rules for tornadoes, lightning and wildfires, floods and flash floods, straight-line thunderstorm winds, hail, and our warning programs.

 

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Severe Weather 101 – Lightning and lightning safety

Friday, April 18th, 2014 10:00am MDT
This is NOT the time to be outside.  (michaeljames / FLICKR)

This is NOT the time to be outside. (michaeljames / FLICKR)

Of all the weather types associated with thunderstorms – hail, tornadoes, floods, etc – lightning is usually the most dangerous. In the United States there are an estimated 25 million cloud to ground lightning flashes each year and each one is a potential threat to life and property.

During the past 10 years there has been an annual average of 39 lightning fatalities in the United States. Last year, 23 people lost their lives due to lightning.

Colorado is ranked # 2 in lightning related deaths (2001 – 2010) so the danger this presents to life and property is very significant for us. It is interesting to note though that Colorado ranks only 32nd in the number of cloud to ground strikes over that same period. Which means, in short, we have fewer strikes than many other states and yet more deaths.

This highlights the fact that, quite frankly, folks here in Colorado are not aware of the dangers lightning presents and they do not take proper steps to protect themselves. One of the great things about Colorado are the outdoor activities we all enjoy, but there comes a time when we need to head indoors.

» Click here to read the rest of Severe Weather 101 – Lightning and lightning safety

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Thornton’s Friday, weekend to feature mild temps, slight chances for storms

Friday, April 18th, 2014 8:19am MDT

We will be heading into the weekend with unseasonably warm temperatures Friday.  Saturday and Sunday will be cooler but still warmer than normal and could bring our first thunderstorms of the season.

For today look for calm conditions, mostly sunny skies, and high temperatures in the upper 70s and pushing the 80 degree mark.

Clouds will be increasing tonight and linger through much of the day Saturday.  The afternoon and evening tomorrow introduce a slight chance for thunderstorms and showers across the area.  Best chances will be in the southern foothills and Palmer Divide area.

A few rain showers will be possible early Sunday then the middle of the day will be dry followed by another slight chance for showers and thunderstorms in the afternoon.  High temperatures will approach 70 degrees.

See the image for your weekend weather outlook and keep an eye on our main page for the latest.

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Severe Weather 101 – Hail and Wind

Thursday, April 17th, 2014 6:15am MDT
Straight line winds can be as damaging as a tornado.  This image is from a park in Tennessee.  (NWS)

Straight line winds can be as damaging as a tornado. This image is from a park in Tennessee. (NWS)

During the spring and summer months in Colorado, a wide array of severe weather can strike. Tornadoes may grab all the headlines, but straight line winds and hail can do a great amount of damage in their own right – and they are more common.

Straight line winds are winds out of a thunderstorm and are classified as severe when they hit 58 mph. These winds can reach tornado and hurricane force and as a result, cause property damage and can injure and even kill animals and humans.

These winds are usually the result of air cooling rapidly due to precipitation or evaporation. As the cooler air is heavier than the surrounding warmer air, it rushes downward, accelerating toward the ground and spreads out as it hits, much like pancake batter being poured onto a griddle.

» Click here to read the rest of Severe Weather 101 – Hail and Wind

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