Alert archive / Colorado / Winter Storm Warnings in 2021

Winter Storm Warning 7, NWS Denver/Boulder, CO

April 27, 20219 counties in Colorado

NWS Denver/Boulder, CO issued this winter storm warning at Apr 27, 2021, 3:16 AM MDT for 9 counties in Colorado. It took effect at Apr 27, 2021, 12:00 PM MDT. It was in force for 22 hr. 48 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Apr 27, 2021, 3:16 AM MDT (09:16 UTC)
In effect from
Apr 27, 2021, 12:00 PM MDT
Expired
Apr 28, 2021, 9:44 AM MDT
In force
22 hr
Issued by
NWS Denver/Boulder, CO

Counties Boulder County, CO, Clear Creek County, CO, Gilpin County, CO, Grand County, CO, Jackson County, CO, Jefferson County, CO, Larimer County, CO, Park County, CO, Summit County, CO

The radar

The Denver radar (KFTG), 102 km from the middle of the area, began a volume at 09:17 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.

What was reported inside it

TimeReportWhereRemark
Apr 28, 5:14 AM MDTSNOW 4.41 W Aspen Springs, CO
Apr 28, 5:20 AM MDTSNOW 31 Nnw Genesee, CO
Apr 28, 5:30 AM MDTSNOW 1.5Wah Keeney Park, COCOCORAHS STATION CO-JF-484 EVERGREEN 1.8 N.
Apr 28, 6:00 AM MDTSNOW 2.53 Sse Silver Plume, COCO-OP OBSERVER STATION GCRC2 GEORGETOWN 4 S.
Apr 28, 6:01 AM MDTSNOW 10.34 Ene Nederland, CO
Apr 28, 6:25 AM MDTSNOW 93 Sse Pinecliffe, COSNOW STILL FALLING AT THE TIME OF THE REPORT.
Apr 28, 6:30 AM MDTSNOW 3.22 Sw Golden, COCOCORAHS STATION CO-JF-497 GOLDEN 1.6 SW.
Apr 28, 6:32 AM MDTSNOW 132 W Jamestown, CO
Apr 28, 7:00 AM MDTSNOW 2.51 Sw Tiny Town, COCOCORAHS STATION CO-JF-537 MORRISON 5.4 SSW.
Apr 28, 7:00 AM MDTSNOW 7.62 S Estes Park, COCOCORAHS STATION CO-LR-767 ESTES PARK 1.8 S.
Apr 28, 8:05 AM MDTSNOW 11 Nne Rabbit Ears Pass, COCOLUMBINE SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 14 Se Mount Zirkel, COZIRKEL SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 15 Ssw Glendevey, CORAWAH SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 15 Wsw Guanella Pass, COJACKWHACKER GULCH SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 19 Se Weston Pass, COROUGH AND TUMBLE SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 210 Nne Silverthorne, COMIDDLE FORK CAMP SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 21 Wnw Loveland Pass, COLOVELAND BASIN SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 27 E Blue River, COMICHIGAN CREEK SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 28 Sse Cameron Pass, COPHANTOM VALLEY SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 29 Sse Gould, CONEVER SUMMER SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 311 S Rabbit Ears Pass, COBUFFALO PARK SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 31 Nw Climax, COFREMONT PASS SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 31 W Copper Mountain, COCOPPER MOUNTAIN SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 41 Nnw Berthoud Pass, COBERTHOUD SUMMIT SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 43 Wnw Alma, COBUCKSKIN JOE SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 51 Ne Echo Lake, COECHO LAKE SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 56 W Arapahoe Peak, COHIGH LONESOME SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 57 Sse Cameron Pass, COLAKE IRENE SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTSNOW 58 Sse Rand, COWILLOW CREEK PASS SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 61 Sw Eldora, COLAKE ELDORA SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 65 Ssw Blue River, COHOOSIER PASS SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 66 Nw Silverthorne, COSUMMIT RANCH SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 75 W Berthoud Falls, COJONES PASS SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 79 Sse Spicer, COARAPAHO RIDGE SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 81 Sse Loveland Pass, COGRIZZLY PEAK SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 83 S Brainard Lake, COUNIVERSITY CAMP SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 85 W Green Mountain Rese, COELLIOT RIDGE SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 93 Sw Ward, CONIWOT SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 111 Nnw Cameron Pass, COJOE WRIGHT SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 114 S Longs Peak, COWILD BASIN SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 118 Nw Glendevey, COROACH SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 123 Sw Meeker Park, COCOPELAND LAKE SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 127 Nw Red Feather Lakes, COBLACK MOUNTAIN SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 143 Nne Mount Audubon, COSAWTOOTH SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 149 Se Cameron Pass, COWILLOW PARK SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 163 Wnw Pingree Park, COHOURGLASS LAKE SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 164 Nnw Longs Peak, COBEAR LAKE SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO
Apr 28, 8:05 AM MDTHEAVY SNOW 169 E Glendevey, CODEADMAN HILL SNOTEL SNOWFALL BETWEEN 12 PM 04/27/2021 AND 6 AM 04/28/2021 ESTIMATED USING A 10 TO 1 SNOW-TO-LIQUID RATIO

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 9.3 hours before the alert went out and 213 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 00:00Z on 2021-04-27Temperature 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 00:00Z on 2021-04-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 15 square meters per square second.1939587897117Sfc1 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
4461 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
15 m²/s²
0-3 km storm-relative helicity
109 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

134 
WWUS45 KBOU 270916
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
316 AM MDT Tue Apr 27 2021

COZ033-034-272130-
/O.UPG.KBOU.WS.A.0004.210427T1800Z-210428T1800Z/
/O.NEW.KBOU.WS.W.0007.210427T1800Z-210428T1800Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-South and
Southeast Grand/West Central and Southwest Boulder/Gilpin/Clear
Creek/Summit/North and West Park Counties Above 9000 Feet-
Including the cities of East Slopes Mosquito Range, Indian Peaks,
Eisenhower Tunnel, Rocky Mountain National Park, East Slopes
Southern Gore Range, Mount Evans, Laramie and Medicine Bow
Mountains, Cameron Pass, Breckenridge, Kenosha Mountains, Winter
Park, Williams Fork Mountains, Willow Creek Pass, Rabbit Ears
Range, and Berthoud Pass
316 AM MDT Tue Apr 27 2021

...WINTER STORM WARNING IN EFFECT FROM NOON TODAY TO NOON MDT 
WEDNESDAY FRONT RANGE MOUNTAINS ABOVE 9000 FEET...

* WHAT...Heavy snow possible. Total snow accumulations of 7 to 14 
  inches possible.

* WHERE...Rocky Mountain National Park and the Medicine Bow Range, 
  and The Mountains of Summit County, the Mosquito Range, and the 
  Indian Peaks.

* WHEN...From Noon today to Noon MDT Wednesday.

* IMPACTS...Roads will likely become slick and hazardous. Travel 
  could be very difficult. The hazardous conditions could impact the 
  Tuesday evening and Wednesday morning commutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Roads will be slick resulting in slow and hazardous travel. Allow 
extra time to reach your destination. The latest road conditions for 
Colorado can be obtained by calling 5 1 1 or by going to www.cotrip.
org


&&

$$

COZ035-272130-
/O.UPG.KBOU.WS.A.0004.210428T0000Z-210428T1800Z/
/O.NEW.KBOU.WS.W.0007.210428T0000Z-210428T1800Z/
Larimer and Boulder Counties Between 6000 and 9000 Feet-
Including the cities of Red Feather Lakes, Glendevey, Nederland,
and Estes Park
316 AM MDT Tue Apr 27 2021

...WINTER STORM WARNING IN EFFECT FROM 6 PM THIS EVENING TO NOON MDT 
WEDNESDAY...

* WHAT...Heavy snow possible. Total snow accumulations of 6 to 12 
  inches possible mainly above 7500 feet.

* WHERE...The Northern Front Range Foothills.

* WHEN...From 6 PM this evening to Noon MDT Wednesday.

* IMPACTS...Roads will likely become slick and hazardous. Travel 
  could be very difficult.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Roads will be slick resulting in slow and hazardous travel. Allow 
extra time to reach your destination. The latest road conditions for 
Colorado can be obtained by calling 5 1 1 or by going to www.cotrip.
org


&&

$$

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

Meier
4 follow-up statements
903 
WWUS45 KBOU 272008
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
208 PM MDT Tue Apr 27 2021

COZ033-034-280415-
/O.CON.KBOU.WS.W.0007.000000T0000Z-210428T1800Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-South and
Southeast Grand/West Central and Southwest Boulder/Gilpin/Clear
Creek/Summit/North and West Park Counties Above 9000 Feet-
Including the cities of East Slopes Mosquito Range, Indian Peaks,
Eisenhower Tunnel, Rocky Mountain National Park, East Slopes
Southern Gore Range, Mount Evans, Laramie and Medicine Bow
Mountains, Cameron Pass, Breckenridge, Kenosha Mountains, Winter
Park, Williams Fork Mountains, Willow Creek Pass, Rabbit Ears
Range, and Berthoud Pass
208 PM MDT Tue Apr 27 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON MDT WEDNESDAY 
FRONT RANGE MOUNTAINS ABOVE 9000 FEET...

* WHAT...Heavy snow expected. Total snow accumulations of 7 to 14 
  inches possible.

* WHERE...Rocky Mountain National Park and the Medicine Bow Range, 
  and The Mountains of Summit County, the Mosquito Range, and the 
  Indian Peaks.

* WHEN...Until Noon MDT Wednesday.

* IMPACTS...Roads will likely become slick and hazardous. The 
  hazardous conditions could impact the Tuesday evening and 
  Wednesday morning commutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you travel, keep an extra flashlight, food, and water in your 
vehicle in case of an emergency. The latest road conditions for 
Colorado can be obtained by calling 5 1 1 or by going to www.cotrip.
org

Roads will be slick resulting in slow and hazardous travel. Allow 
extra time to reach your destination.

&&

$$

COZ035-280415-
/O.CON.KBOU.WS.W.0007.210428T0000Z-210428T1800Z/
Larimer and Boulder Counties Between 6000 and 9000 Feet-
Including the cities of Red Feather Lakes, Glendevey, Nederland,
and Estes Park
208 PM MDT Tue Apr 27 2021

...WINTER STORM WARNING REMAINS IN EFFECT FROM 6 PM THIS EVENING TO 
NOON MDT WEDNESDAY...

* WHAT...Heavy snow expected. Total snow accumulations of 6 to 12 
  inches possible, mainly above 7500 feet.

* WHERE...The Northern Front Range Foothills.

* WHEN...From 6 PM this evening to Noon MDT Wednesday.

* IMPACTS...Roads will likely become slick and hazardous. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you travel, keep an extra flashlight, food, and water in your 
vehicle in case of an emergency. The latest road conditions for 
Colorado can be obtained by calling 5 1 1 or by going to www.cotrip.
org

Roads will be slick resulting in slow and hazardous travel. Allow 
extra time to reach your destination.

&&

$$

COZ036-280415-
/O.NEW.KBOU.WW.Y.0027.210428T0300Z-210428T1800Z/
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Including the cities of Evergreen, Georgetown, Westcreek, Central
City, Idaho Springs, and Bailey
208 PM MDT Tue Apr 27 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 9 PM THIS EVENING TO NOON 
MDT WEDNESDAY...

* WHAT...Snow expected. Total snow accumulations 2 to 10 inches, 
  heaviest above 7500 feet.

* WHERE...The Southern Front Range Foothills.

* WHEN...From 9 PM this evening to Noon MDT Wednesday.

* IMPACTS...Travel could be slick and hazardous. This could include 
  the Wednesday morning commute.

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

&&

$$

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

Barjenbruch
258 
WWUS45 KBOU 280331
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
931 PM MDT Tue Apr 27 2021

COZ033-034-281145-
/O.CON.KBOU.WS.W.0007.000000T0000Z-210428T1800Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-South and
Southeast Grand/West Central and Southwest Boulder/Gilpin/Clear
Creek/Summit/North and West Park Counties Above 9000 Feet-
Including the cities of East Slopes Mosquito Range, Indian Peaks,
Eisenhower Tunnel, Rocky Mountain National Park, East Slopes
Southern Gore Range, Mount Evans, Laramie and Medicine Bow
Mountains, Cameron Pass, Breckenridge, Kenosha Mountains, Winter
Park, Williams Fork Mountains, Willow Creek Pass, Rabbit Ears
Range, and Berthoud Pass
931 PM MDT Tue Apr 27 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON MDT WEDNESDAY 
FRONT RANGE MOUNTAINS ABOVE 9000 FEET...

* WHAT...Heavy snow expected. Total snow accumulations of 7 to 14 
  inches possible.

* WHERE...Rocky Mountain National Park and the Medicine Bow Range, 
  and The Mountains of Summit County, the Mosquito Range, and the 
  Indian Peaks.

* WHEN...Until Noon MDT Wednesday.

* IMPACTS...Roads will likely become slick and hazardous. Travel 
  could be very difficult. The hazardous conditions could impact the 
  Wednesday morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in 
your vehicle in case of an emergency. The latest road conditions for 
Colorado can be obtained by calling 5 1 1 or by going to www.cotrip.
org

Roads will be slick resulting in slow and hazardous travel. Allow 
extra time to reach your destination.

&&

$$

COZ035-281145-
/O.CON.KBOU.WS.W.0007.000000T0000Z-210428T1800Z/
Larimer and Boulder Counties Between 6000 and 9000 Feet-
Including the cities of Red Feather Lakes, Glendevey, Nederland,
and Estes Park
931 PM MDT Tue Apr 27 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON MDT WEDNESDAY...

* WHAT...Heavy snow expected. Total snow accumulations of 6 to 12 
  inches possible, mainly above 7500 feet.

* WHERE...The Northern Front Range Foothills.

* WHEN...Until Noon MDT Wednesday.

* IMPACTS...Roads will likely become slick and hazardous. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you travel, keep an extra flashlight, food, and water in your 
vehicle in case of an emergency. The latest road conditions for 
Colorado can be obtained by calling 5 1 1 or by going to www.cotrip.
org

Roads will be slick resulting in slow and hazardous travel. Allow 
extra time to reach your destination.

&&

$$

COZ036-281145-
/O.CON.KBOU.WW.Y.0027.000000T0000Z-210428T1800Z/
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Including the cities of Evergreen, Georgetown, Westcreek, Central
City, Idaho Springs, and Bailey
931 PM MDT Tue Apr 27 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL NOON MDT 
WEDNESDAY...

* WHAT...Snow expected. Total snow accumulations 2 to 10 inches, 
  heaviest above 7500 feet.

* WHERE...The Southern Front Range Foothills.

* WHEN...Until Noon MDT Wednesday.

* IMPACTS...Travel could be slick and hazardous. This could include 
  the Wednesday morning commute.

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

&&

$$

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

Kriederman
697 
WWUS45 KBOU 280913
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
313 AM MDT Wed Apr 28 2021

COZ033-034-281800-
/O.CON.KBOU.WS.W.0007.000000T0000Z-210428T1800Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-South and
Southeast Grand/West Central and Southwest Boulder/Gilpin/Clear
Creek/Summit/North and West Park Counties Above 9000 Feet-
Including the cities of East Slopes Mosquito Range, Indian Peaks,
Eisenhower Tunnel, Rocky Mountain National Park, East Slopes
Southern Gore Range, Mount Evans, Laramie and Medicine Bow
Mountains, Cameron Pass, Breckenridge, Kenosha Mountains, Winter
Park, Williams Fork Mountains, Willow Creek Pass, Rabbit Ears
Range, and Berthoud Pass
313 AM MDT Wed Apr 28 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON MDT TODAY FRONT 
RANGE MOUNTAINS ABOVE 9000 FEET...

* WHAT...Heavy snow expected. Total snow accumulations of 7 to 14 
  inches possible.

* WHERE...Rocky Mountain National Park and the Medicine Bow Range, 
  and The Mountains of Summit County, the Mosquito Range, and the 
  Indian Peaks.

* WHEN...Until Noon MDT today.

* IMPACTS...Roads are slick and hazardous in places. Plan on 
  slippery road conditions this morning. The hazardous conditions 
  will impact the Wednesday morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Roads will be slick resulting in slow and hazardous travel. Allow 
extra time to reach your destination. The latest road conditions for 
Colorado can be obtained by calling 5 1 1 or by going to www.cotrip.
org

&&

$$

COZ035-281800-
/O.CON.KBOU.WS.W.0007.000000T0000Z-210428T1800Z/
Larimer and Boulder Counties Between 6000 and 9000 Feet-
Including the cities of Red Feather Lakes, Glendevey, Nederland,
and Estes Park
313 AM MDT Wed Apr 28 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON MDT TODAY...

* WHAT...Heavy snow expected. Total snow accumulations of 6 to 12 
  inches possible, mainly above 7500 feet.

* WHERE...The Northern Front Range Foothills.

* WHEN...Until Noon MDT today.

* IMPACTS...Roads are slick and hazardous in places. Plan on 
  slippery road conditions this morning.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Roads will be slick resulting in slow and hazardous travel. Allow 
extra time to reach your destination. The latest road conditions for 
Colorado can be obtained by calling 5 1 1 or by going to www.cotrip.
org


&&

$$

COZ036-281800-
/O.CON.KBOU.WW.Y.0027.000000T0000Z-210428T1800Z/
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Including the cities of Evergreen, Georgetown, Westcreek, Central
City, Idaho Springs, and Bailey
313 AM MDT Wed Apr 28 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL NOON MDT TODAY...

* WHAT...Snow expected. Total snow accumulations 2 to 10 inches, 
  heaviest above 7500 feet.

* WHERE...The Southern Front Range Foothills.

* WHEN...Until Noon MDT today.

* IMPACTS...Roads are slick and hazardous in places. Plan on 
  slippery road conditions this morning. The hazardous conditions 
  will impact the Wednesday morning commute.

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

&&

$$

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

Meier
266 
WWUS45 KBOU 281544
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
944 AM MDT Wed Apr 28 2021

COZ033>035-281645-
/O.CAN.KBOU.WS.W.0007.000000T0000Z-210428T1800Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-South and
Southeast Grand/West Central and Southwest Boulder/Gilpin/Clear
Creek/Summit/North and West Park Counties Above 9000 Feet-Larimer
and Boulder Counties Between 6000 and 9000 Feet-
Including the cities of Glendevey, East Slopes Mosquito Range,
Estes Park, Indian Peaks, Nederland, Eisenhower Tunnel, Rocky
Mountain National Park, East Slopes Southern Gore Range, Mount
Evans, Laramie and Medicine Bow Mountains, Red Feather Lakes,
Cameron Pass, Breckenridge, Kenosha Mountains, Winter Park,
Williams Fork Mountains, Willow Creek Pass, Rabbit Ears Range,
and Berthoud Pass
944 AM MDT Wed Apr 28 2021

...WINTER STORM WARNING IS CANCELLED...

Heavy snow has ended. Only scattered light showers can be expected 
through the rest of today.

$$

COZ036-281645-
/O.CAN.KBOU.WW.Y.0027.000000T0000Z-210428T1800Z/
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Including the cities of Evergreen, Georgetown, Westcreek, Central
City, Idaho Springs, and Bailey
944 AM MDT Wed Apr 28 2021

...WINTER WEATHER ADVISORY IS CANCELLED...

Snow will continue to diminish. Only scattered light showers can be 
expected through the rest of today.

$$

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

Barjenbruch

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 27, 1:52 AM MDTSevere Thunderstorm WarningBOUWashington23 min
Apr 27, 11:35 AM MDTSpecial Weather StatementBOUDouglas25 min
Apr 27, 11:55 AM MDTSpecial Weather StatementBOUElbert50 min
Apr 27, 11:59 AM MDTSpecial Weather StatementBOUDenver31 min
Apr 27, 12:49 PM MDTSevere Thunderstorm WarningBOUAdams, Weld26 min
Apr 27, 1:15 PM MDTSpecial Weather StatementBOUAdams45 min
Apr 27, 1:51 PM MDTSpecial Weather StatementBOULincoln39 min
Apr 27, 1:53 PM MDTSpecial Weather StatementBOUWeld37 min
Apr 27, 1:59 PM MDTSevere Thunderstorm WarningBOUWeld31 min
Apr 27, 2:02 PM MDTSevere Thunderstorm WarningBOUElbert28 min
Apr 27, 2:08 PM MDTWinter Weather AdvisoryBOUClear Creek, Douglas, Gilpin, Jefferson, Park20 hr
Apr 27, 2:23 PM MDTSevere Thunderstorm WarningBOUElbert, Lincoln52 min
Apr 27, 2:43 PM MDTSevere Thunderstorm WarningBOUAdams, Morgan32 min
Apr 27, 2:49 PM MDTSevere Thunderstorm WarningBOUElbert, Lincoln41 min
Apr 27, 3:00 PM MDTSpecial Weather StatementBOULincoln45 min
Apr 27, 3:10 PM MDTSpecial Weather StatementBOUMorgan20 min
Apr 27, 3:13 PM MDTSevere Thunderstorm WarningBOUAdams, Morgan, Washington32 min
Apr 27, 3:28 PM MDTSevere Thunderstorm WarningBOULincoln47 min
Apr 27, 3:32 PM MDTSpecial Weather StatementBOUMorgan28 min
Apr 27, 3:41 PM MDTTornado WarningBOULincoln34 min
Apr 27, 4:12 PM MDTSevere Thunderstorm WarningBOULincoln33 min
Apr 27, 4:16 PM MDTSevere Thunderstorm WarningBOULogan, Morgan, Washington17 min
Apr 27, 4:36 PM MDTTornado WarningBOULincoln24 min
Apr 27, 5:19 PM MDTSevere Thunderstorm WarningBOUWashington26 min
Apr 27, 5:51 PM MDTSpecial Weather StatementBOUPhillips24 min

Nearby

Winter Storm Warnings in Colorado, 2021Every winter storm warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.