Alert archive / Colorado / Winter Storm Warnings in 2020

Winter Storm Warning 3, NWS Denver/Boulder, CO

February 15, 20204 counties in Colorado

NWS Denver/Boulder, CO issued this winter storm warning at Feb 15, 2020, 4:07 AM MST for 4 counties in Colorado. It took effect at Feb 15, 2020, 9:00 PM MST. It was in force for 35 hr. 60 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
Feb 15, 2020, 4:07 AM MST (11:07 UTC)
In effect from
Feb 15, 2020, 9:00 PM MST
Expired
Feb 17, 2020, 8:00 AM MST
In force
35 hr
Issued by
NWS Denver/Boulder, CO

Counties Boulder County, CO, Grand County, CO, Jackson County, CO, Larimer County, CO

The radar

The Cheyenne radar (KCYS), 121 km from the middle of the area, began a volume at 11:06 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
Feb 16, 3:48 AM MSTSNOW 4.51 W Fraser, CO
Feb 16, 7:00 AM MSTSNOW 32 Ssw Elkdale, COCOCORAHS STATION CO-GR-68 TABERNASH 2.7 NW.
Feb 16, 8:00 AM MSTSNOW 8.82 Sse Winter Park, COCO-OP OBSERVER STATION WTPC2 1.5 SE WINTER PARK.
Feb 16, 11:30 AM MSTSNOW 82 Sse Tabernash, CO
Feb 16, 1:49 PM MSTSNOW 81 Nw Grand Lake, CO
Feb 17, 4:18 AM MSTSNOW 1.43 Sw Meeker Park, COCOPELAND LAKE SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTSNOW 1.43 Sw Meeker Park, COCOPELAND LAKE SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTSNOW 4.210 Nne Silverthorne, COMIDDLE FORK CAMP SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTSNOW 4.210 Nne Silverthorne, COMIDDLE FORK CAMP SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTSNOW 4.25 Ssw Glendevey, CORAWAH SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTSNOW 4.25 Ssw Glendevey, CORAWAH SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTSNOW 5.63 Sw Ward, CONIWOT SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTSNOW 5.63 Sw Ward, CONIWOT SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTSNOW 5.63 Wnw Pingree Park, COHOURGLASS LAKE SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTSNOW 5.63 Wnw Pingree Park, COHOURGLASS LAKE SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTSNOW 5.68 Nw Glendevey, COROACH SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTSNOW 5.68 Nw Glendevey, COROACH SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 74 S Longs Peak, COWILD BASIN SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 74 S Longs Peak, COWILD BASIN SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 75 W Berthoud Falls, COJONES PASS SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 75 W Berthoud Falls, COJONES PASS SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 78 Sse Cameron Pass, COPHANTOM VALLEY SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 78 Sse Cameron Pass, COPHANTOM VALLEY SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 8.41 Sw Eldora, COLAKE ELDORA SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 8.41 Sw Eldora, COLAKE ELDORA SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 8.43 S Brainard Lake, COUNIVERSITY CAMP SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 8.43 S Brainard Lake, COUNIVERSITY CAMP SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 8.44 Nnw Longs Peak, COBEAR LAKE SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 8.44 Nnw Longs Peak, COBEAR LAKE SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 8.45 Wsw Grand Lake, COSTILLWATER CREEK SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 8.45 Wsw Grand Lake, COSTILLWATER CREEK SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 8.49 E Glendevey, CODEADMAN HILL SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 8.49 E Glendevey, CODEADMAN HILL SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 8.49 Sse Gould, CONEVER SUMMER SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 8.49 Sse Gould, CONEVER SUMMER SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 9.81 Nnw Berthoud Pass, COBERTHOUD SUMMIT SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 9.81 Nnw Berthoud Pass, COBERTHOUD SUMMIT SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 11.211 S Rabbit Ears Pass, COBUFFALO PARK SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 11.211 S Rabbit Ears Pass, COBUFFALO PARK SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 11.28 Sse Rand, COWILLOW CREEK PASS SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 11.28 Sse Rand, COWILLOW CREEK PASS SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 12.63 Nne Mount Audubon, COSAWTOOTH SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 12.63 Nne Mount Audubon, COSAWTOOTH SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 12.65 Wsw Winter Park, COFOOL CREEK SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 12.65 Wsw Winter Park, COFOOL CREEK SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 12.67 Sse Cameron Pass, COLAKE IRENE SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 12.67 Sse Cameron Pass, COLAKE IRENE SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 12.69 Se Cameron Pass, COWILLOW PARK SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 12.69 Se Cameron Pass, COWILLOW PARK SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 15.46 W Arapahoe Peak, COHIGH LONESOME SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 15.46 W Arapahoe Peak, COHIGH LONESOME SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 15.49 Sse Spicer, COARAPAHO RIDGE SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 15.49 Sse Spicer, COARAPAHO RIDGE SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 16.81 Nnw Cameron Pass, COJOE WRIGHT SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 16.81 Nnw Cameron Pass, COJOE WRIGHT SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 214 Se Mount Zirkel, COZIRKEL SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 214 Se Mount Zirkel, COZIRKEL SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 4:18 AM MSTHEAVY SNOW 23.81 Nne Rabbit Ears Pass, COCOLUMBINE SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 17, 4:18 AM MSTHEAVY SNOW 23.81 Nne Rabbit Ears Pass, COCOLUMBINE SNOTEL SNOWFALL BETWEEN 8 PM 02/15/2020 AND 2 AM 02/17/2020 ESTIMATED USING A 14.0 TO 1 SNOW-TO-LIQUID RATIO.
Feb 17, 7:00 AM MSTSNOW 1.13 N Pinecliffe, COCOCORAHS STATION CO-BO-110 NEDERLAND 4.8 ENE.

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, 11.1 hours before the alert went out and 227 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 2020-02-15Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 00:00Z on 2020-02-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 45 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
3175 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
45 m²/s²
0-3 km storm-relative helicity
144 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

394 
WWUS45 KBOU 151107
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
407 AM MST Sat Feb 15 2020

...THE NEXT ROUND OF MOUNTAIN SNOWFALL IS EXPECTED LATE TONIGHT 
INTO MONDAY...

.Strong moist, northwest to westerly flow aloft, will bring 
snow to the mountains of north central Colorado late tonight 
into Monday. The heaviest snow can be expected from Sunday 
through early Monday morning. Strong winds will accompany the 
snow, with gusts to 60 mph, causing blowing and drifting snow 
along with poor visibilities. Difficult travel conditions can be 
expected in the mountains Sunday into Monday.

COZ031-033-151915-
/O.UPG.KBOU.WS.A.0004.200216T0700Z-200218T0000Z/
/O.NEW.KBOU.WS.W.0003.200216T0600Z-200218T0000Z/
Rabbit Ears Pass-
Rocky Mountain National Park and the Medicine Bow Range-
Including the cities of East Slopes Park and Northern Gore
Ranges, Gore Pass, Rabbit Ears Pass, Cameron Pass, 
Laramie and Medicine Bow Mountains, Rabbit Ears Range, 
Rocky Mountain National Park, and Willow Creek Pass
407 AM MST Sat Feb 15 2020

...WINTER STORM WARNING IN EFFECT FROM 11 PM THIS EVENING TO 5 PM
MST MONDAY...

* WHAT...Heavy snow expected. Total snow accumulations of 15 to 30 
  inches. Winds gusting as high as 60 mph.

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

* WHEN...From 11 PM this evening to 5 PM MST Monday.

* IMPACTS...Travel could be very difficult to impossible. Areas of
  blowing snow could significantly reduce visibility. The 
  hazardous conditions could impact the morning or evening 
  commute. Gusty winds could bring down tree branches.

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 the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

COZ034-151915-
/O.EXT.KBOU.WS.A.0004.200216T0600Z-200218T0000Z/
The Mountains of Summit County, the Mosquito Range, and the
Indian Peaks-
Including the cities of Berthoud Pass, Breckenridge, 
East Slopes Mosquito Range, East Slopes Southern Gore Range, 
Eisenhower Tunnel, Indian Peaks, Kenosha Mountains, Mount Evans, 
Williams Fork Mountains, and Winter Park
407 AM MST Sat Feb 15 2020

...WINTER STORM WATCH REMAINS IN EFFECT FROM LATE THIS EVENING 
THROUGH MONDAY AFTERNOON...

* WHAT...Heavy snow possible. Total snow accumulations of 10 to 18
  inches possible. Winds could gust as high as 60 mph.

* WHERE...Mountains of Summit County, the Mosquito Range, and the
  Indian Peaks.

* WHEN...From this evening through Monday afternoon.

* IMPACTS...Travel could be very difficult to impossible. Areas 
  of blowing snow could significantly reduce visibility. The 
  hazardous conditions are expected to impact the morning or 
  evening commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$
5 follow-up statements
710 
WWUS45 KBOU 152047
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
147 PM MST Sat Feb 15 2020

...THE NEXT ROUND OF MOUNTAIN SNOWFALL IS EXPECTED LATE TONIGHT
INTO MONDAY...

.Strong moist, northwest to westerly flow aloft, will bring snow
to the mountains of north central Colorado tonight into Monday. 
The heaviest snow can be expected from Sunday through early Monday
morning. Strong winds will accompany the snow, with gusts to 60 
mph, causing blowing and drifting snow along with poor 
visibilities. Difficult travel conditions can be expected in the 
mountains Sunday into Monday.

COZ031-033-161200-
/O.EXT.KBOU.WS.W.0003.200216T0400Z-200217T1500Z/
Rabbit Ears Pass-
Rocky Mountain National Park and the Medicine Bow Range-
Including the cities of East Slopes Park and Northern Gore
Ranges, Gore Pass, Rabbit Ears Pass, Cameron Pass, 
Laramie and Medicine Bow Mountains, Rabbit Ears Range, 
Rocky Mountain National Park, and Willow Creek Pass
147 PM MST Sat Feb 15 2020

...WINTER STORM WARNING NOW IN EFFECT FROM 9 PM THIS EVENING TO
8 AM MST MONDAY...

* WHAT...Heavy snow expected. Total snow accumulations of 1 to 3
  feet. Winds gusting as high as 60 mph.

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

* WHEN...From 9 PM this evening to 8 AM MST Monday.

* IMPACTS...Travel could be very difficult to impossible. Areas 
  of blowing snow could significantly reduce visibility. The 
  hazardous conditions could impact the morning or evening 
  commute. Gusty winds could bring down tree branches.

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 the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

COZ034-161200-
/O.UPG.KBOU.WS.A.0004.200216T0600Z-200218T0000Z/
/O.NEW.KBOU.WW.Y.0010.200216T0400Z-200217T1500Z/
The Mountains of Summit County, the Mosquito Range, and the
Indian Peaks-
Including the cities of Berthoud Pass, Breckenridge, 
East Slopes Mosquito Range, East Slopes Southern Gore Range, 
Eisenhower Tunnel, Indian Peaks, Kenosha Mountains, Mount Evans, 
Williams Fork Mountains, and Winter Park
147 PM MST Sat Feb 15 2020

...WINTER WEATHER ADVISORY IN EFFECT FROM 9 PM THIS EVENING TO
8 AM MST MONDAY...

* WHAT...Snow expected. Total snow accumulations of 7 to 15 
  inches. Winds gusting as high as 50 mph.

* WHERE...The Mountains of Summit County, the Mosquito Range, 
  and the Indian Peaks.

* WHEN...From 9 PM this evening to 8 AM MST Monday.

* IMPACTS...Travel could be very difficult to impossible. Patchy 
  blowing snow could significantly reduce visibility. The 
  hazardous conditions could impact the morning or evening 
  commute. Gusty winds could bring down tree branches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
756 
WWUS45 KBOU 161041
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
341 AM MST Sun Feb 16 2020

...MODERATE TO HEAVY MOUNTAIN SNOWFALL AND STRONG WINDS INTO 
MONDAY...

.Abundant moisture in strong northwest flow aloft will bring snow
to the mountains of north central Colorado through Monday morning.
The heaviest snow can be expected this evening and overnight as a
front pushes down. Strong winds will cause blowing and drifting 
snow along with poor visibilities. Difficult travel conditions can
be expected in the mountains today and especially this evening and
overnight.

COZ031-033-161930-
/O.CON.KBOU.WS.W.0003.000000T0000Z-200217T1500Z/
Rabbit Ears Pass-
Rocky Mountain National Park and the Medicine Bow Range-
Including the cities of East Slopes Park and Northern Gore
Ranges, Gore Pass, Rabbit Ears Pass, Cameron Pass, 
Laramie and Medicine Bow Mountains, Rabbit Ears Range, 
Rocky Mountain National Park, and Willow Creek Pass
341 AM MST Sun Feb 16 2020

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 8 AM MST MONDAY...

* WHAT...Heavy snow. Additional snow accumulations of 6 to 17
  inches, heaviest over the Park Range. Winds gusting as high as 
  50 mph.

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

* WHEN...Until 8 AM MST Monday, with heaviest snowfall rates
  expected this evening and overnight.

* IMPACTS...Travel may become very difficult to impossible. Patchy
  blowing snow can significantly reduce visibility. The hazardous
  conditions will impact the morning commute and even more so for
  the evening commute. Gusty winds and heavy snowfall could cause
  tree damage.

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 the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

COZ034-161930-
/O.CON.KBOU.WW.Y.0010.000000T0000Z-200217T1500Z/
The Mountains of Summit County, the Mosquito Range, and the
Indian Peaks-
Including the cities of Berthoud Pass, Breckenridge, 
East Slopes Mosquito Range, East Slopes Southern Gore Range, 
Eisenhower Tunnel, Indian Peaks, Kenosha Mountains, Mount Evans, 
Williams Fork Mountains, and Winter Park
341 AM MST Sun Feb 16 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 8 AM MST
MONDAY...

* WHAT...Snow. Additional snow accumulations of 3 to 14 inches.
  Highest amounts found over the Gore Range. Winds gusting as 
  high as 50 mph.

* WHERE...The Mountains of Summit County, the Mosquito Range, 
  and the Indian Peaks.

* WHEN...Until 8 AM MST Monday, with heaviest snowfall rates
  expected overnight.

* IMPACTS...Travel may become very difficult to impossible. Patchy
  blowing snow can significantly reduce visibility. The hazardous
  conditions will impact the morning commute and even more so for
  the evening commute. Gusty winds and heavy snowfall could cause
  tree damage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
204 
WWUS45 KBOU 162007
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
107 PM MST Sun Feb 16 2020

...MODERATE TO HEAVY MOUNTAIN SNOWFALL AND STRONG WINDS INTO
MONDAY...

.Abundant moisture in strong northwest flow aloft will continue to
bring snow to the mountains of north central Colorado through 
Monday morning. The heaviest snow can be expected this evening and
overnight as a cold front pushes down. Strong winds will cause 
blowing and drifting snow along with poor visibilities. Difficult 
travel conditions can be expected in the mountains today and 
especially this evening and overnight.

COZ031-033-170615-
/O.CON.KBOU.WS.W.0003.000000T0000Z-200217T1500Z/
Rabbit Ears Pass-
Rocky Mountain National Park and the Medicine Bow Range-
Including the cities of East Slopes Park and Northern Gore
Ranges, Gore Pass, Rabbit Ears Pass, Cameron Pass, 
Laramie and Medicine Bow Mountains, Rabbit Ears Range, 
Rocky Mountain National Park, and Willow Creek Pass
107 PM MST Sun Feb 16 2020

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 8 AM MST MONDAY...

* WHAT...Heavy snow. Additional snow accumulations of 6 to 17 
  inches, heaviest over the Park Range. Winds gusting as high as 
  50 mph.

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

* WHEN...Until 8 AM MST Monday, with heaviest snowfall rates 
  expected this evening and overnight.

* IMPACTS...Travel may become very difficult to impossible. 
  Patchy blowing snow can significantly reduce visibility. The 
  hazardous conditions will impact the morning commute and even 
  more so for the evening commute. Gusty winds and heavy 
  snowfall could cause tree damage.


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 the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

COZ034-170615-
/O.CON.KBOU.WW.Y.0010.000000T0000Z-200217T1500Z/
The Mountains of Summit County, the Mosquito Range, and the
Indian Peaks-
Including the cities of Berthoud Pass, Breckenridge, 
East Slopes Mosquito Range, East Slopes Southern Gore Range, 
Eisenhower Tunnel, Indian Peaks, Kenosha Mountains, Mount Evans, 
Williams Fork Mountains, and Winter Park
107 PM MST Sun Feb 16 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 8 AM MST
MONDAY...

* WHAT...Snow. Additional snow accumulations of 3 to 14 inches. 
  Highest amounts found over the Gore Range. Winds gusting as 
  high as 50 mph.

* WHERE...The Mountains of Summit County, the Mosquito Range, 
  and the Indian Peaks.

* WHEN...Until 8 AM MST Monday, with heaviest snowfall rates 
  expected overnight.

* IMPACTS...Travel may become very difficult to impossible. 
  Patchy blowing snow can significantly reduce visibility. The 
  hazardous conditions will impact the morning commute and even 
  more so for the evening commute. Gusty winds and heavy 
  snowfall could cause tree damage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
958 
WWUS45 KBOU 170444
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
944 PM MST Sun Feb 16 2020

...MODERATE TO HEAVY MOUNTAIN SNOWFALL AND STRONG WINDS INTO
MONDAY...

.Abundant moisture in strong northwest flow aloft will continue
to bring snow to the mountains of north central Colorado through
Monday morning. The heaviest snow can be expected this evening
and overnight as a cold front pushes down. Strong winds will
cause blowing and drifting snow along with poor visibilities.
Difficult travel conditions can be expected in the mountains
today and especially this evening and overnight.

COZ031-033-171500-
/O.CON.KBOU.WS.W.0003.000000T0000Z-200217T1500Z/
Rabbit Ears Pass-
Rocky Mountain National Park and the Medicine Bow Range-
Including the cities of East Slopes Park and Northern Gore
Ranges, Gore Pass, Rabbit Ears Pass, Cameron Pass, 
Laramie and Medicine Bow Mountains, Rabbit Ears Range, 
Rocky Mountain National Park, and Willow Creek Pass
944 PM MST Sun Feb 16 2020

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 8 AM MST MONDAY...

* WHAT...Heavy snow. Additional snow accumulations of 3 to 6 
  inches. Winds gusting as high as 50 mph.

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

* WHEN...Until 8 AM MST Monday, with heaviest snowfall rates 
  expected this evening and overnight.

* IMPACTS...Travel may be very difficult to impossible. Patchy
  blowing snow can significantly reduce visibility. The hazardous
  conditions will impact the 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 the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

COZ034-171500-
/O.CON.KBOU.WW.Y.0010.000000T0000Z-200217T1500Z/
The Mountains of Summit County, the Mosquito Range, and the
Indian Peaks-
Including the cities of Berthoud Pass, Breckenridge, 
East Slopes Mosquito Range, East Slopes Southern Gore Range, 
Eisenhower Tunnel, Indian Peaks, Kenosha Mountains, Mount Evans, 
Williams Fork Mountains, and Winter Park
944 PM MST Sun Feb 16 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 8 AM MST
MONDAY...

* WHAT...Snow. Additional snow accumulations of 2 to 5 inches. 
  Winds gusting as high as 45 mph.

* WHERE...The Mountains of Summit County, the Mosquito Range, 
  and the Indian Peaks.

* WHEN...Until 8 AM MST Monday, with heaviest snowfall rates 
  expected overnight.

* IMPACTS...Travel may become very difficult to impossible. Patchy
  blowing snow can significantly reduce visibility. The hazardous
  conditions will impact the morning commute. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
505 
WWUS45 KBOU 171042
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
342 AM MST Mon Feb 17 2020

COZ031-033-171500-
/O.CON.KBOU.WS.W.0003.000000T0000Z-200217T1500Z/
Rabbit Ears Pass-
Rocky Mountain National Park and the Medicine Bow Range-
Including the cities of East Slopes Park and Northern Gore
Ranges, Gore Pass, Rabbit Ears Pass, Cameron Pass, 
Laramie and Medicine Bow Mountains, Rabbit Ears Range, 
Rocky Mountain National Park, and Willow Creek Pass
342 AM MST Mon Feb 17 2020

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 8 AM MST THIS
MORNING...

* WHAT...Snow, decreasing and diminishing by noon. Additional 
  snow accumulations of up to two inches. Winds gusting as high as
  45 mph.

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

* WHEN...Until 8 AM MST this morning.

* IMPACTS...Plan on slippery road conditions. Patchy blowing 
  snow could significantly reduce visibility. The hazardous 
  conditions could impact the 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 the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

COZ034-171500-
/O.CON.KBOU.WW.Y.0010.000000T0000Z-200217T1500Z/
The Mountains of Summit County, the Mosquito Range, and the
Indian Peaks-
Including the cities of Berthoud Pass, Breckenridge, 
East Slopes Mosquito Range, East Slopes Southern Gore Range, 
Eisenhower Tunnel, Indian Peaks, Kenosha Mountains, Mount Evans, 
Williams Fork Mountains, and Winter Park
342 AM MST Mon Feb 17 2020

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 8 AM MST THIS
MORNING...

* WHAT...Snow, decreasing and diminishing by noon. Additional 
  snow accumulations of up to two inches. Winds gusting as high as
  45 mph.

* WHERE...The Mountains of Summit County, the Mosquito Range, 
  and the Indian Peaks.

* WHEN...Until 8 AM MST this morning.

* IMPACTS...Plan on slippery road conditions. Areas of blowing 
  snow could significantly reduce visibility. The hazardous 
  conditions could impact the morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

What forecasters said that day

The local office's own words before this winter storm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Denver/Boulder, CO wrote its last area forecast discussion before this winter storm warning went out at Feb 15, 3:43 AM MST, 24 minutes earlier.

Area forecast discussion, Feb 15, 3:43 AM MST, 24 minutes before
Area Forecast Discussion
National Weather Service Denver/Boulder CO
343 AM MST Sat Feb 15 2020

.SHORT TERM...(Today and tonight)
Issued at 240 AM MST Sat Feb 15 2020

A cold front has pushed across the area with little snow over the
mountains. Flow aloft will become more northwesterly over the
state today and tonight as a strong jet moves in from the Pacific
Northwest. This jet will be pushing in higher precipitable water
amounts as it transports an atmospheric river across the western
US. Current values around 0.1 inch will increase to around 0.25
inches by early Sunday morning. Even though QG motion will be
downward, orographics will squeeze out the available moisture over
the mountains, with snow beginning later this afternoon into the
evening, increasing in intensity after midnight. By sunrise,
amounts of 4 to 8 inches may have already fallen, with highest
amounts over the Park Range north of Rabbit Ears Pass. The
incoming jet will also increase winds over the high terrain, with
gusts in the 40 to 50 mph range over the higher elevations. A
Winter Storm Warning will go into effect after midnight to
highlight these hazardous conditions.

Over the plains, temperatures will be cooler than yesterday behind
last night's cold front. Readings will likely only reach into the
40s, with partly cloudy skies. Temperatures will then drop tonight
into the upper teens to mid 20s with mostly cloudy skies.

.LONG TERM...(Sunday through Friday)
Issued at 152 AM MST Sat Feb 15 2020

Moisture embedded in WNW flow aloft, will affect the mtns Sun
into Mon, with a favorable orographic component. Deepest moisture
will be from Sun through Sun night with lapse rates around 6
c/km. Meanwhile, position of upper level jet, will likely allow
for periods of heavier banded snowfall as well in some areas north
of I-70. In addition, will see areas of blowing snow and poor
visbilities as well. At this time, the heaviest amounts will be
over portions of zns 31 and 33, with 18 to 36 inches. The I-70
mtn corridor of zn 34 may see amounts in the 8 to 18 inch range.

Over nern CO, it will be dry on Sun, with warmer temps, as highs
reach the upper 40s to mid 50's. For Sun night, a cool front will
move across nern CO with possibly some weak upslope and
frontogenesis. Meanwhile, there will be an upper level jet
overhead, with cross-sections showing some potential for banded
precip, if enough moisture is available overnight into early Mon
morning. Overall confidence, isn't high at the moment, with this
scenario, so have just kept pops in the chc category along the
front range and plains.

During the day on Mon, the flow aloft will remain WNW, however,
cross-sections show moisture depth decreasing in the mtns.  Thus
snowfall should be lighter. Across nern CO, not sure about precip
chances in the aftn. Cross-sections would suggest it will be dry,
however, blended solutions are yielding 40-50 pops. There is
still a jet overhead, so I guess I can't completely rule out a
chc of precip, if there is more moisture around than is currently
shown. As far as highs, it will be cooler with readings in the
mid 30s to lower 40s.

For Mon night into Tue morning, an upper level trough will move
across the area.  This feature has favorable mid level ascent with
it, along with an increase in moisture. In addition, a secondary
surge of colder air will move across nern CO as well. Thus one
would think there would be a good chance of snow along the front
range and portions of the plains Mon night into early Tue. In
addition, as the trough moves across, should see an increase in
snowfall across the mtns as well. As for highs on Tue readings
will drop into the upper 20s to mid 30s over nern CO.

For Tue night into Wed, drier air will move into the area in NW
flow aloft. Thus snow chances should diminish in the mtns. At
lower elevations, there is still weak upslope flow with a shallow
layer of moisture up to 700 mb, along the front range thru Wed.
In addition, there is a disturbance embbeded in the flow aloft,
which could help generate a chc of light snow on Wed in and near
the foothills. Highs on Wed will remain cold.

&&

.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 240 AM MST Sat Feb 15 2020

VFR conditions will prevail through Saturday night with ceilings
expected to remain above 10kft. Easterly post-frontal winds will
slowly end up southerly around or a little after 12Z. Southeast
winds are expected to prevail through today, through a Denver
Cyclone will likely form and should remain north or northwest of
DEN. However, if it shifts a little south, this may bring
northerly or northwesterly winds to DEN later this afternoon into
the evening. Otherwise, drainage winds are expected to return
tonight.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Storm Watch from this evening through Monday afternoon
for COZ034.

Winter Storm Warning from 11 PM this evening to 5 PM MST Monday
for COZ031-033.

&&

SHORT TERM...Kriederman
LONG TERM...RPK
AVIATION...Kriederman
Hazardous weather outlook, Feb 15, 4:00 AM MST, 7 minutes before
Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
400 AM MST Sat Feb 15 2020

COZ030>051-161100-
Jackson County Below 9000 Feet-
West Jackson and West Grand Counties Above 9000 Feet-
Grand and Summit Counties Below 9000 Feet-
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-
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Central and Southeast Park County-
Larimer County Below 6000 Feet/Northwest Weld County-
Boulder And Jefferson Counties Below 6000 Feet/West Broomfield
County-
North Douglas County Below 6000 Feet/Denver/West Adams and
Arapahoe Counties/East Broomfield County-
Elbert/Central and East Douglas Counties Above 6000 Feet-
Northeast Weld County-Central and South Weld County-Morgan County-
Central and East Adams and Arapahoe Counties-
North and Northeast Elbert County Below 6000 Feet/North Lincoln
County-
Southeast Elbert County Below 6000 Feet/South Lincoln County-
Logan County-Washington County-Sedgwick County-Phillips County-
400 AM MST Sat Feb 15 2020

...Winter Storm Warning for the northern mountains late tonight
through Monday...
...Winter Storm Watch for the I-70 Mountain Corridor late tonight
through Monday...

This hazardous weather outlook is for northeast and north central
Colorado.

.DAY ONE...Today and Tonight

Expect a cooler day today in a post frontal airmass. Winds and
snow will increase beginning this afternoon over the high country.
Snowfall rates will increase rapidly after midnight, with an inch
per hour possible, especially over the Park Range north of Rabbit
Ears Pass. Winds gusting 40 to 50 mph overnight will create areas
of blowing snow. Travel is expected to be impacted, with snow
packed roads along with blowing and drifting snow expecially after
midnight. Travelers need to plan ahead as the heavier snow will
continue into Sunday.

It will be dry with seasonable temperatures across the plains.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Periods of snow will continue in the mountains through Sunday
night and will be heavy at times. Gusty winds up to 60 mph will
produce widespread blowing snow and poor visibilities over the
higher passes. The snow will continue on Monday but will be
lighter. Travel will be difficult in the mountains Sunday into
Monday.

Across the plains, there will be a chance of light snow Sunday
night into Monday. A weather disturbance and associated cold front
will bring a good chance of snow to the entire area Monday night
into Tuesday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight.

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 15, 1:47 PM MSTWinter Weather AdvisoryBOUBoulder, Clear Creek, Gilpin, Grand, Jefferson, Park and 1 more42 hr

Nearby

Winter Storm Warnings in Colorado, 2020Every winter storm warning in 2020

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.