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Life threatening winter weather – Wind chill, frostbite and hypothermia

Thursday, October 22nd, 2020 4:00am MST
Wind chill is a life threatening weather danger that is often ignored or underestimated. (AP Photo)

Wind chill is a life threatening weather danger that is often ignored or underestimated.

Winter weather can not only be trying on the mind and soul, it also presents very real dangers to the human body.  Extreme wind chills can be deadly and bring on the outset of frostbite and hypothermia.  Here in Colorado, all residents should be aware of these hazards and be prepared to deal with them.

In this fourth in a series on Winter Weather Preparedness from the National Weather Service, ThorntonWeather.com helps you understand wind chill and how to protect yourself from frostbite and hypothermia.

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
ISSUED BY NATIONAL WEATHER SERVICE GOODLAND KS
600 AM MDT THU OCT 22 2020

Extreme wind chill – Potentially life-threatening and often overlooked

Extremely cold air comes every winter in at least part of the country and affects millions of people across the United States. The arctic air, combined with brisk winds, can lead to dangerously cold wind chill values. The Wind Chill Index helps you determine when dangerous conditions develop that could lead to frostbite or hypothermia. It takes into account heat loss from the human body to its surroundings during cold and windy weather. The calculation utilizes wind speed in miles per hour and temperature in degrees Fahrenheit. For example, a temperature of minus 5 degrees occurring with a 20 mph wind gives a wind chill near minus 30 degrees. This means that your body will lose heat at the same rate as it would if the air temperature were minus 30 degrees with no wind. Wind Chill values near minus 25 degrees mean that frostbite is possible within 15 minutes.

  • How does the wind affect wind chill?  See the chart below.

Frostbite is the freezing of skin and the body tissue just beneath it. It first affects exposed body tissue where blood circulation may be limited such as your fingers, toes, nose and ears. To minimize frostbite, make sure all body parts are well covered. When frostbite starts, feeling is lost in the affected area and the frozen tissue will take on a white or pale appearance. If you suspect you are experiencing frostbite, hold the frostbitten area closely against warm skin to return blood flow and warmth to the affected area.

Hypothermia is a dangerously low body temperature and is the most common winter weather killer. When you hear of a hiker, climber, hunter or a stranded traveler perishing from cold weather exposure, hypothermia was the cause. Most people are surprised to learn that hypothermia deaths can occur with temperatures between 30 and 50 degrees. If you or your clothing are wet, then hypothermia becomes even more likely.

Warning signs of hypothermia include uncontrollable shivering, memory loss, disorientation, slurred speech and drowsiness. Immediate medical attention should be given to victims suspected of suffering from hypothermia. If no help is available, the victim should be warmed slowly with warm liquids along with dry clothing and blankets.

The National Weather Service will issue wind chill advisories and warnings when a deadly combination of wind and cold air threaten. To learn more about wind chill, visit the national weather service internet site using lower case letters:  http://weather.gov/om/windchill.

When cold weather threatens, follow these tips for survival:

Stay dry, wet clothing results in much faster heat loss from your body. Wear waterproof insulated boots.

Stay covered, wear mittens or gloves and wear a hat. At least half of your body heat is lost if your head is not covered.

Dress layered, trapped air between loose fitting clothing helps to insulate.

Stay informed, have a portable NOAA weather radio nearby to keep you up-to-date with the latest forecasts and warnings. Use wind chill temperatures to guide you in dressing properly for the outdoors. On very cold days, minimize your exposure to the outdoors if possible.

Winter Weather - Extreme Cold Safety

Winter Weather - Signs of Hypothermia

Wind Chill Chart

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Comfortable temps, calm conditions, some smoke for Thornton’s Wednesday

Wednesday, October 21st, 2020 5:41am MST

One more chance for a mild day before things start turning toward the cooler side tomorrow.

Partly sunny skies will be above today with some smoke in the afternoon. Right now we are expecting a high today in the low 70s. However, the cloud cover may impact temperatures, as it has the last two days.

Tonight, smoke should ease after dark and we will be left with partly clear skies. Overnight lows will dip to the low to mid-40s.

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High winds a major threat in Colorado during the winter

Wednesday, October 21st, 2020 4:59am MST
Winter winds can not only make it miserable to be outside, they can also be dangerous.

Winter winds can not only make it miserable to be outside, they can also be dangerous.

As we often experience, high winds in Colorado can cause conditions to deteriorate rapidly.  They present a very real danger to life and property, especially when coupled with other winter conditions like snow.

Why does it seem like we get so much wind in the winter?  What causes this?  How can you prepare and protect yourself and your property?

In this third in a series on winter weather preparedness from the National Weather Service, ThorntonWeather.com helps you understand why we receive so much wind and how to prepare for it.

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE BOULDER CO
ISSUED BY NATIONAL WEATHER SERVICE PUEBLO CO
600 AM MDT WED OCT 21 2020

…WIDESPREAD HIGH WINDS VISIT COLORADO DURING THE WINTER…

This week through October 19th is Winter Weather Preparedness Week in Colorado.

The two main causes of high winds in Colorado during the cold season are the air pressure difference between strong low pressure and cold high pressure systems, and Chinook winds developing across the Front Range and other eastern mountain ranges.

» Click here to read the rest of High winds a major threat in Colorado during the winter

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Tuesday’s weather to offer somewhat mild temps, calm conditions

Tuesday, October 20th, 2020 5:08am MST

A pretty nice-looking fall day ahead for Thornton. We should be able to shake off the cool temps that lingered yesterday and enjoy a relatively mild day.

Mostly sunny skies start us off and will be with us throughout the day. The afternoon is again expected to bring some smoke from the wildfires to the west. Overall conditions will be calm and dry with highs in the low 70s.

Tonight, partly cloudy skies will be above with lows dipping to the upper 30s.

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Winter weather – What does that weather warning mean?

Tuesday, October 20th, 2020 4:49am MST
You have seen and heard the warnings but do you know what they really mean?

You have seen and heard the warnings but do you know what they really mean?

We all are familiar with the crawls on the TV screen or the announcements on the radio for winter weather advisories such as Winter Storm Watch, Blizzard Warning, Freeze Warning and more. But, how many of us really know what those mean? There is very specific criteria the National Weather Service follows in issuing these watches and warnings and there are important differences between all of them.

In this second in a series on Winter Weather Preparedness from the National Weather Service, ThorntonWeather.com helps you understand what all of these mean so you can be better prepared.

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE BOULDER CO
600 AM TUE OCT 20 2020

From the National Weather Service:

What does that warning mean?

When a warning is issued during the winter season, will you know what it means, and will you know how to respond? During this Colorado Winter Weather Preparedness Week, please become familiar with our list of potentially life-saving winter weather products.

This statement contains warning and advisory criteria for Colorado east of the continental divide. Criteria west of the divide will be provided today in a separate issuance by the Grand Junction forecast office.

Outlooks

A Hazardous Weather Outlook is issued daily by each National Weather Service office serving Colorado. The outlook provides information on potentially hazardous weather out to 7 days into the future. Also, the Weather Story, a graphic of expected hazardous weather, is posted daily on National Weather Service web sites serving Colorado.

Watches and Warnings

A Winter Storm Watch is issued when hazardous winter storm conditions are possible within the next 3 to 4 days, but the timing, intensity, or occurrence may still be uncertain.

In contrast, a Winter Storm Warning is issued for potentially life-threatening winter storm conditions, such as heavy snowfall or a combination of snowfall and blowing snow, which are likely to occur within the next 1 to 2 days.

Warning criteria for heavy snow is defined by the following amounts.

  • For the mountains – 8 inches of snow accumulation in 12 hours or 12 or more inches in 24 hours.
  • For the lower elevations – 6 inches of snow accumulation in 12 hours or 8 or more inches in 24 hours.

A Blizzard Warning is issued when the following conditions are expected to occur for at least 3 hours:

  • Sustained winds of 35 mph or greater.
  • Considerable falling and/or drifting snow lowering
  • Visibilities to less than a quarter mile.

A high wind warning is issued:

  • Mountains…sustained winds 50 mph or more, or gusts of at least 75 mph.
  • Lower Elevations…sustained winds of 40 mph or more, or gusts of at least 58 mph

A Wind Chill Warning will be issued for the following wind chill temperatures:

  • Mountains…minus 35 degrees Fahrenheit or colder.
  • Lower Elevations…minus 25 degrees Fahrenheit or colder.

A Dust Storm Warning will be issued for the following conditions:

  • Visibility reduced to 1/4 mile or less in blowing dust and sustained winds of 25 mph or greater for at least one hour.

Advisories

Advisories for winter weather are issued for potentially hazardous conditions which are considered more of a nuisance than a life-threatening situation. However, if caution is not taken the advisory events could become life-threatening

This week is Winter Weather Preparedness Week in Colorado. Public information statements will be issued throughout the week to give safety information and help you know how to respond when winter weather threatens.

Winter weather watches and advisories.

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Mild temperatures, some cloud cover and smoke for Thornton’s Monday weather

Monday, October 19th, 2020 5:17am MST

We recover from this past weekend’s cold front today and will enjoy warmer temperatures and overall pleasant conditions. However, winds to the west will likely lead to increased fire activity and bring smoke our way.

Mostly sunny skies start us off. We will see a few more clouds as the morning progresses but still have spots of blue and sun. Highs today will top out in the low 70s, well above the average high for the date of 64 degrees.

Here at lower elevations and to the east, we aren’t expecting winds to amount to much. However, in the foothills and high country, it will be breezy. That will increase the fire activity and will bring smoke our way this afternoon and evening.

Tonight, lows will drop to the low 40s under partly cloudy skies.

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Winter travel safety – Ensure you and your vehicle are ready

Monday, October 19th, 2020 5:05am MST
Are you and your vehicle ready for the winter weather ahead?

Are you and your vehicle ready for the winter weather ahead?

Before hitting the road, Coloradans need to ensure that they and their vehicles are prepared should inclement weather strike.

ThorntonWeather.com presents the first in a series from the National Weather Service (NWS) as part of Winter Weather Preparedness Week has declared by Colorado’s Governor.  Check back throughout the week for more winter preparedness stories.

Today’s message from the NWS highlights the importance of having a proper emergency kit in your vehicle and should the worst-case scenario occur where you get stuck, what you should do to survive.

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
601 AM MDT MON OCT 19 2020

Winter Travel Safety

Winter Weather Preparedness Week continues through Saturday.  Preparedness is a big part of this campaign. Before winter weather arrives in earnest, it is highly recommended that you prepare your car or truck for winter travel.

A well equipped vehicle has adequate tires, tire chains, tow rope, sand or cat litter for traction, shovel, tool kit, windshield scraper and brush, battery cables, first aid kit, flashlight, extra batteries, blankets and/or sleeping bags, extra clothing, candles, water-proof matches, high calorie packaged food for quick energy and an empty can to melt snow for drinking.

The best way to prevent treacherous winter travel is to avoid it. This can be done by staying informed about current weather and road conditions as well as the latest weather forecasts. Information on road conditions in Colorado is available on the web at www.cotrip.org or from the toll free number 1-877-315-7623. When calling from anywhere in Colorado, dialing 511 will also access the Colorado road reports. Additionally, a free smartphone application, CDOT Mobile, is available.

If you should become stranded during a winter storm, stay with your vehicle an d do not panic. If accompanied by others, take turns sleeping. Run the motor every hour for about ten minutes to maintain warmth, but keep windows open a little to prevent the buildup of carbon monoxide. Make sure the exhaust pipe is not blocked. Keep the car visible with brightly colored cloths tied to the side view mirrors, door handles, or external antenna. At night, turn on the dome light when running the engine. Exercise periodically by vigorously moving arms, legs, toes and fingers.

In the mountains, avalanches become a possibility in the winter, especially below steep slopes. Avalanches occasionally come down across roads, with little or no warning. However, avalanche control work is performed on many avalanche prone roads in Colorado, making the roads safer to travel. Caution is advised when traveling along avalanche prone roads, especially during and shortly after a heavy snowstorm or during periods of rapid snowmelt.

Very strong downslope winds occur at times mainly along the front range of Colorado. These Chinook and Bora winds can have gusts exceeding 100 mph. Persons traveling in light weight or high profile vehicles should avoid travel during these strong wind events especially on north-south oriented roads.

Roads which appear to be clear in the wintertime may actually be coated with a thin layer of ice, commonly known as black ice. This nearly invisible ice layer can cause you to rapidly lose control of your vehicle. Black ice is most common during the nighttime hours. If you detect black ice you should reduce your speed.

Please follow these winter travel safety recommendations which could save your life.

Winter Weather Awareness Week - Winter Travel Safety. (National Weather Service)

Winter Weather Awareness Week – Winter Travel Safety. (National Weather Service)

 

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October 18 to October 24: This week in Denver weather history

Sunday, October 18th, 2020 5:44pm MST

This Week in Denver Weather History

This week is an extremely eventful one in Denver weather history with a wide variety of conditions having been experienced in the past. Wind and snow are probably the two most dominant items, none more so than the blizzard that struck 23 years ago on the 24th. That storm ravaged the city, closed the airport and highways and was responsible for four deaths.

From the National Weather Service:

From the 17th to the 19th:

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

On the 18th:

In 1875…the haze was so dense that the mountains were not visible from downtown Denver for most of the day.

In 1937…a vigorous cold front produced north winds sustained to 32 mph with gusts to 41 mph. Rain and snow totaled 0.16 inch. Post-frontal snowfall of 0.8 inch was the only snowfall of the month.

In 1960…post-frontal upslope rain changed to snow. Snowfall was 2.2 inches at Stapleton Airport where precipitation (rain and melted snow) totaled 1.58 inches.

In 1971…wind gusts to 48 mph were recorded in downtown Boulder. West winds gusted to 30 mph at Stapleton International Airport.

In 1999…heavy snow developed in the foothills west of metro Denver with lesser amounts across the city. Snowfall totals included: 7 inches near Nederland…6 inches in Boulder…and 5 inches at Chief Hosa. Only 1.2 inches of snow were measured at the site of the former Stapleton International Airport.

From the 18th to the 23rd:

In 2003…an extended warm spell resulted in 5 new temperature records. The high temperature of 84 degrees on the 18th equaled the record high for the date. High temperatures of 86 degrees on the 19th…83 degrees on the 21st…and 84 degrees on the 22nd were record highs for the dates. Low temperature of 49 degrees on the 23rd was a record high minimum for the date. Low temperatures during the period were in the 40’s and lower 50’s.

On the 19th:

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

In 1982…3 to 6 inches of snow fell over northwest metro Denver…including Boulder. Only 1.2 inches of snowfall were recorded at Stapleton International Airport where north winds gusted to 35 mph. This was the first measurable snowfall of the season.

From the 19th to the 20th:

In 1990…an early winter storm dumped heavy snow across metro Denver. Snowfall amounts ranged from 4 to 8 inches in the foothills above 6500 feet elevation…4 to 7 inches in the Castle Rock area…and 2 to 5 inches across most of metro Denver and Boulder. Snowfall totaled 3.6 inches at Stapleton International Airport where northwest winds gusting to 48 mph kicked up some blowing dust shortly after a cold frontal passage on the 19th. However… Temperatures were warm enough to keep most roadways wet and slushy at lower elevations.

From the 19th to the 23rd:

In 1906…heavy snowfall totaled 22.7 inches in the city over the 5 days. Rain changed to snow on the evening of the 19th…and snow continued through the late afternoon of the 23rd. The heaviest amount of snowfall…16.0 inches…fell from 8:00 pm on the 20th to 8:00 pm on the 22nd. The most snow on the ground was 13.3 inches on the evening of the 23rd. This was the first snow of the season and the only snow of the month. Winds during the storm were from the north at sustained speeds of 20 to 30 mph each day. Temperatures during the storm were generally in the 20’s.

On the 20th:

In 1878…between 3:00 pm and 4:00 pm wind speeds averaged 48 mph with a maximum 1 minute sustained velocity to 96 mph at both 3:27 pm and 3:48 pm in downtown Denver. This is the highest sustained wind speed ever recorded in the city.

In 1986…a rare late October thunderstorm produced 3/4 inch diameter hail at Centennial Airport. Hail piled up 2 1/2 inches deep…causing some street flooding in south metro Denver.

From the 20th to the 21st:

In 2007…a storm system brought heavy snow to the southern Denver suburbs as well as the Palmer Divide south of Denver. Storm totals included: 7.5 inches near Castle Rock…Lone Tree and Greenwood Village…with 6.5 inches at Elizabeth. Snow drifts up to 2 feet deep were observed 6 miles south-southwest of Elizabeth. In the Denver Stapleton area…2.0 inches of snow was observed.

In 2009…heavy snow developed along the Palmer Divide south and southeast of Denver as a storm system tracked across southern Colorado and northern New Mexico. Storm totals included: 15 inches…15 miles north of Elizabeth…9 inches… 5 miles south-southwest of Arapahoe Park; 8 inches in Highlands Ranch…5 miles south- southeast of Sedalia; 6.5 inches…8 miles southwest of Bennett and 6 inches in Parker. At Denver international… Only 1.5 inches of snowfall was observed.

From the 20th to the 22nd:

In 1936…5.5 inches of snow fell over downtown Denver. Most of the snow…4.5 inches…fell on the 20th.

On the 21st:

In 1920…the rare event of snow from a thunderstorm occurred in the city during the evening. Brilliant flashes of lightning and loud peals of thunder were first noted at 7:35 pm. Light rain began falling at 8:30 pm…and light moist snow began falling a few minutes later. Some soft hail was also seen falling with the rain and snow…but both melted almost as fast as they fell. The hail only continued for a few minutes…and the rain and snow ceased about 9:40 pm. The snowfall was the first to occur in Denver this season. The amount of precipitation at the station measured only 0.01 inch…but heavier amounts were reported from other parts of the city. Snowfall was only a trace.

From the 21st to the 22nd:

In 1978…heavy rain on the 21st changed to snow by daybreak on the 22nd and continued the rest of the day. This was the first measurable snowfall of the season…but totaled only 1.7 inches at Stapleton International Airport where east winds gusted to 29 mph. While only a trace of snow covered the ground…precipitation totaled 1.27 inches.

On the 22nd:

In 1878…winds were sustained to 42 mph.

In 1887…the first measurable snow of the season occurred… Ending the longest snow-free period in Denver…232 days… Since the last snow on march 5th.

In 1947…the first snow of the season totaled only 1.6 inches. Post-frontal north winds caused temperatures to plunge from a high of 60 degrees at midnight to a low of only 30 degrees 24 hours later. This was the only snow of the month.

In 1985…high winds gusting from 60 to 80 mph buffeted the Front Range foothills. The strongest reported wind gust was 89 mph in eastern Boulder. A treehouse east of Boulder was set on fire by a downed power line. Two people in Boulder were injured. A woman broke her arm when the strong winds knocked her to the ground. A carpenter in the city suffered a severely cut hand while he was trying to repair a roof that was being torn from a building. At Stapleton International Airport…northwest winds gusted to 41 mph.

In 2001…west-northwest winds gusting as high as 54 mph warmed the temperature to a high of 70 degrees at Denver International Airport.

» Click here to read the rest of October 18 to October 24: This week in Denver weather history

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Colorado Winter Weather Preparedness Week introduction

Sunday, October 18th, 2020 5:30am MST
Don't be caught off guard by winter weather! Remember the Christmas Eve Blizzard of 1982? Be prepared!

Don’t be caught off guard by winter weather! Remember the Christmas Eve Blizzard of 1982? Be prepared!

Winter weather in Colorado can be an inconvenience but more than that it can be deadly.  Emergency preparedness for major winter storms – as well as for other types of severe weather – is an important part of living in a state where conditions can change wildly from one moment to the next.

To help raise awareness of the need to be prepared for these occasions, the week of October 18th to October 24th has been proclaimed Winter Weather Preparedness Week in Colorado.

The National Weather Service will be issuing Public Information Statements each day this week to highlight the dangers of winter weather and how best to be prepared.  ThorntonWeather.com will be posting these important messages here to help you be prepared.  Please take the time to read and heed these messages – your life and the lives of your loved ones could depend on it.

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From the National Weather Service:

Public Information Statement
National Weather Service
Grand Junction CO

..Winter Weather Preparedness Week in Colorado…

The week of October 18th through October 24th is Winter Weather Preparedness Week in Colorado. This is an excellent time for all individuals, families, businesses, schools, and media outlets to review their winter storm preparedness plans. It is especially important for all new arrivals to the state to become familiar with the National Weather Service watch and warning definitions, as well as winter safety procedures.

Snow in Colorado is important to the farmers, the ski areas, and for filling up reservoirs. However, winter storms often bring heavy snow, bitter cold air, high winds, low visibilities and slick roads. This can lead to dangerous travel conditions and other life threatening situations such as avalanches and very frigid wind chill temperatures.

To help you prepare for these hazards this coming winter…the National Weather Service will issue statements throughout the week to discuss:

Intro Winter Weather Preparedness Week
Part 1 Winter travel safety
Part 2 Watches…warnings…and advisories
Part 3 High winds
Part 4 Wind chill temperatures and hypothermia
Part 5 Avalanche safety
Review Winter Weather Preparedness Week review
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Thornton’s weekend to start off mild, end on the cool side

Friday, October 16th, 2020 5:15am MST

A little bit of a mixed bag of temperatures for us this weekend. We start out near normal, warm up a bit Saturday, then will cool down on Sunday.

For today, mostly sunny skies will be above and conditions will be calm and dry. Highs will be in the upper 60s. Tonight, lows will drop to the low 40s under partly cloudy skies.

Saturday will be the warmest day of the period with highs in the mid-70s. Mostly sunny skies will be above with some breezy winds. A cold front will be arriving in the evening and that will allow overnight temperatures into Sunday morning to drop to near freezing.

Sunday will feel the effects of the front with highs only reaching the mid-50s under partly sunny skies. Have a great weekend!

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