Alert archive / Colorado / Wind Chill Advisories in 2021

Wind Chill Advisory 1, NWS Denver/Boulder, CO

February 11, 20218 counties in Colorado

NWS Denver/Boulder, CO issued this wind chill advisory at Feb 11, 2021, 1:17 PM MST for 8 counties in Colorado. It took effect at Feb 13, 2021, 12:00 AM MST. It was in force for .

The area

The counties it named.

The facts

Issued
Feb 11, 2021, 1:17 PM MST (20:17 UTC)
In effect from
Feb 13, 2021, 12:00 AM MST
Expired
Feb 11, 2021, 1:45 PM MST
In force
Issued by
NWS Denver/Boulder, CO

Counties Elbert County, CO, Lincoln County, CO, Logan County, CO, Morgan County, CO, Phillips County, CO, Sedgwick County, CO, Washington County, CO, Weld County, CO

The radar

The Denver radar (KFTG), 109 km from the middle of the area, began a volume at 20:17 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 8.3 hours before the alert went out and 34 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Denver, CO at 12:00Z on 2021-02-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 12:00Z on 2021-02-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 86 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1436 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
86 m²/s²
0-3 km storm-relative helicity
269 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

399 
WWUS45 KBOU 112017
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
117 PM MST Thu Feb 11 2021

COZ042-044-046-048>051-120700-
/O.NEW.KBOU.WC.Y.0001.210213T0700Z-210213T2300Z/
Northeast Weld County-Morgan County-North and Northeast Elbert
County Below 6000 Feet/North Lincoln County-Logan County-
Washington County-Sedgwick County-Phillips County-
Including the cities of Wiggins, Fort Morgan, Hugo, Otis,
Julesburg, Sedgwick, Briggsdale, Sterling, Pawnee Buttes, Cope,
Akron, Raymer, Amherst, Ovid, Matheson, Peetz, Grover, Agate,
Haxtun, Last Chance, Goodrich, Stoneham, Crook, Holyoke, Brush,
Limon, and Merino
117 PM MST Thu Feb 11 2021

...WIND CHILL ADVISORY IN EFFECT FROM MIDNIGHT FRIDAY NIGHT TO 4 PM 
MST SATURDAY...

* WHAT...Very cold wind chills expected. Wind chills as low as 20 
  below zero.

* WHERE...Portions of east central and northeast Colorado.

* WHEN...From Midnight Friday Night to 4 PM MST Saturday.

* IMPACTS...The dangerously cold wind chills could cause frostbite 
  on exposed skin in as little as 30 minutes. Frostbite and 
  hypothermia are possible if precautions are not taken.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The combination of wind and cold temperatures will create 
dangerously low wind chill values. If you go outside, cover all 
parts of your body, especially your head, face, and hands.

Pets are also susceptible to the extremely cold weather. Keep pets 
indoors as much as possible. If this is not possible, make sure 
outdoor pets have a warm, dry shelter, and provide sufficient food 
and fresh water.

&&

$$

COZ031-120700-
/O.CON.KBOU.WW.Y.0010.210212T0000Z-210213T1200Z/
West Jackson and West Grand Counties Above 9000 Feet-
Including the cities of Mt Zirkel
117 PM MST Thu Feb 11 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 5 PM THIS 
AFTERNOON TO 5 AM MST SATURDAY...

* WHAT...Snow expected. Total snow accumulations between 10 to 18 
  inches. Winds gusting as high as 35 mph.

* WHERE...Rabbit Ears Pass.

* WHEN...From 5 PM this afternoon to 5 AM MST Saturday.

* IMPACTS...Travel could be very difficult to impossible. Roads will 
  become slippery in spots, especially through mountain passes. Use 
  caution when traveling.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions for Colorado can be obtained by calling 5 1 1 or by going 
to www.cotrip.org

&&

$$

COZ033-120700-
/O.CON.KBOU.WW.Y.0010.210212T0000Z-210213T1200Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-
Including the cities of Laramie and Medicine Bow Mountains,
Rabbit Ears Range, Cameron Pass, Rocky Mountain National Park,
and Willow Creek Pass
117 PM MST Thu Feb 11 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 5 PM THIS 
AFTERNOON TO 5 AM MST SATURDAY...

* WHAT...Snow expected. Total snow accumulations between 6 to 12 
  inches. Winds gusting as high as 40 mph.

* WHERE...Rocky Mountain National Park and the Medicine Bow Range.

* WHEN...From 5 PM this afternoon to 5 AM MST Saturday.

* IMPACTS...Travel could be very difficult. Snow covered roads will 
  make travel hazardous.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions for Colorado can be obtained by calling 5 1 1 or by going 
to www.cotrip.org

Slow down and use caution while traveling. Allow extra time to reach 
your destination.

&&

$$

For more information from the National Weather Service, visit 
https://weather.gov/bou

Cooper
1 follow-up statement
429 
WWUS45 KBOU 112045
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
145 PM MST Thu Feb 11 2021

COZ042-044-046-048>051-120600-
/O.CAN.KBOU.WC.Y.0001.210213T0700Z-210213T2300Z/
/O.NEW.KBOU.WC.Y.0002.210212T0700Z-210212T2300Z/
Northeast Weld County-Morgan County-North and Northeast Elbert
County Below 6000 Feet/North Lincoln County-Logan County-
Washington County-Sedgwick County-Phillips County-
Including the cities of Wiggins, Fort Morgan, Hugo, Otis,
Julesburg, Sedgwick, Briggsdale, Sterling, Pawnee Buttes, Cope,
Akron, Raymer, Amherst, Ovid, Matheson, Peetz, Grover, Agate,
Haxtun, Last Chance, Goodrich, Stoneham, Crook, Holyoke, Brush,
Limon, and Merino
145 PM MST Thu Feb 11 2021

...WIND CHILL ADVISORY IN EFFECT FROM MIDNIGHT TONIGHT TO 4 PM MST 
FRIDAY...


* WHAT...Very cold wind chills expected. Wind chills as low as 20 
  below zero.

* WHERE...Portions of east central and northeast Colorado.

* WHEN...From midnight tonight through 4 pm MST on Friday

* IMPACTS...The dangerously cold wind chills could cause frostbite 
  on exposed skin in as little as 30 minutes. Frostbite and 
  hypothermia are possible if precautions are not taken.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The combination of wind and cold temperatures will create 
dangerously low wind chill values. If you go outside, cover all 
parts of your body, especially your head, face, and hands.

Pets are also susceptible to the extremely cold weather. Keep pets 
indoors as much as possible. If this is not possible, make sure 
outdoor pets have a warm, dry shelter, and provide sufficient food 
and fresh water.

&&

$$

COZ031-120600-
/O.CON.KBOU.WW.Y.0010.210212T0000Z-210213T1200Z/
West Jackson and West Grand Counties Above 9000 Feet-
Including the cities of Mt Zirkel
145 PM MST Thu Feb 11 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 5 PM THIS 
AFTERNOON TO 5 AM MST SATURDAY...

* WHAT...Snow expected. Total snow accumulations between 10 to 18 
  inches. Winds gusting as high as 35 mph.

* WHERE...Rabbit Ears Pass.

* WHEN...From 5 PM this afternoon to 5 AM MST Saturday.

* IMPACTS...Travel could be very difficult to impossible. Roads will 
  become slippery in spots, especially through mountain passes. Use 
  caution when traveling.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions for Colorado can be obtained by calling 5 1 1 or by going 
to www.cotrip.org

&&

$$

COZ033-120600-
/O.CON.KBOU.WW.Y.0010.210212T0000Z-210213T1200Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-
Including the cities of Laramie and Medicine Bow Mountains,
Rabbit Ears Range, Cameron Pass, Rocky Mountain National Park,
and Willow Creek Pass
145 PM MST Thu Feb 11 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 5 PM THIS 
AFTERNOON TO 5 AM MST SATURDAY...

* WHAT...Snow expected. Total snow accumulations between 6 to 12 
  inches. Winds gusting as high as 40 mph.

* WHERE...Rocky Mountain National Park and the Medicine Bow Range.

* WHEN...From 5 PM this afternoon to 5 AM MST Saturday.

* IMPACTS...Travel could be very difficult. Snow covered roads will 
  make travel hazardous.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions for Colorado can be obtained by calling 5 1 1 or by going 
to www.cotrip.org

Slow down and use caution while traveling. Allow extra time to reach 
your destination.

&&

$$

For more information from the National Weather Service, visit 
https://weather.gov/bou

Entrekin

The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 11, 4:10 AM MSTWinter Weather AdvisoryBOUBoulder, Grand, Jackson, Larimer49 hr
Feb 11, 1:45 PM MSTWind Chill AdvisoryBOUAdams, Arapahoe, Boulder, Broomfield, Denver, Douglas and 10 more4 days

Nearby

Wind Chill Advisories in Colorado, 2021Every wind chill advisory in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.