Alert archive / Colorado / Winter Storm Warnings in 2018

Winter Storm Warning 3, NWS Denver/Boulder, CO

February 14, 20189 counties in Colorado

NWS Denver/Boulder, CO issued this winter storm warning at Feb 14, 2018, 3:19 AM MST for 9 counties in Colorado. It took effect at Feb 14, 2018, 5:00 PM MST. It was in force for 25 hr. 28 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 14, 2018, 3:19 AM MST (10:19 UTC)
In effect from
Feb 14, 2018, 5:00 PM MST
Expired
Feb 15, 2018, 6:00 PM MST
In force
25 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 10:22 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 15, 4:00 AM MSTSNOW 35 Sw Glendevey, COMESONET STATION RAWC2, 5 SW GLENDEVEY.
Feb 15, 5:00 AM MSTSNOW 76 W Four Corners, COMESONET STATION ROAC2, 6 W FOUR CORNERS.
Feb 15, 6:00 AM MSTSNOW 25 Nnw Trail Ridge, COMESONET STATION LRVC2, 5 NNW TRAIL RIDGE.
Feb 15, 6:00 AM MSTSNOW 78 Ese Four Corners, COMESONET STATION DDMC2, 8 ESE FOUR CORNERS.
Feb 15, 7:00 AM MSTSNOW 3.1Frisco, COCOCORAHS STATION CO-SU-4, FRISCO.
Feb 15, 7:00 AM MSTSNOW 5Hohnholz Ranch, COCO-OP OBSERVER STATION HORC2, HOHNHOLZ RANCH.
Feb 15, 8:00 AM MSTSNOW 31 W Copper Mountain, COMESONET STATION CPMC2, 1 W COPPER MOUNTAIN.
Feb 15, 8:00 AM MSTSNOW 35 Nnw Trail Ridge, COMESONET STATION LRVC2, 5 NNW TRAIL RIDGE.
Feb 15, 8:00 AM MSTSNOW 3.52 Sse Breckenridge, CO
Feb 15, 8:00 AM MSTSNOW 48 Se Rand, COMESONET STATION WLLC2, 8 SE RAND.
Feb 15, 8:00 AM MSTSNOW 61 Nnw Cameron Pass, COMESONET STATION JWRC2, 1 NNW CAMERON PASS.
Feb 15, 8:00 AM MSTSNOW 68 Ese Four Corners, COMESONET STATION DDMC2, 8 ESE FOUR CORNERS.
Feb 15, 8:00 AM MSTSNOW 75 Sw Glendevey, COMESONET STATION RAWC2, 5 SW GLENDEVEY.
Feb 15, 8:23 AM MSTSNOW 1.51 Sse Loveland Pass, COGRIZZLY PEAK SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTSNOW 1.53 Wnw Alma, COBUCKSKIN JOE SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTSNOW 1.53 Wnw Pingree Park, COHOURGLASS LAKE SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTSNOW 1.57 Sse Cameron Pass, COLAKE IRENE SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTSNOW 1.58 Sse Rand, COWILLOW CREEK PASS SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTSNOW 31 Nne Rabbit Ears Pass, COCOLUMBINE SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTSNOW 31 Nw Climax, COFREMONT PASS SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTSNOW 31 W Copper Mountain, COCOPPER MOUNTAIN SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTSNOW 4.57 Nw Red Feather Lakes, COBLACK MOUNTAIN SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTSNOW 4.59 E Glendevey, CODEADMAN HILL SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTHEAVY SNOW 65 Ssw Glendevey, CORAWAH SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTHEAVY SNOW 65 W Berthoud Falls, COJONES PASS SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTHEAVY SNOW 68 Nw Glendevey, COROACH SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTHEAVY SNOW 7.59 Ene Steamboat Springs, COTOWER SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 TO 1 SNOW-TO-LIQUID RATIO
Feb 15, 8:23 AM MSTHEAVY SNOW 10.54 Se Mount Zirkel, COZIRKEL SNOTEL SNOWFALL BETWEEN 4 PM 02/14/2018 AND 7 AM 02/15/2018 ESTIMATED USING A 15.0 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 (KDEN), launched 00:00Z, 10.3 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 2018-02-14Temperature 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 2018-02-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 54 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
2631 m above ground
0-6 km bulk shear
67 kt
0-1 km storm-relative helicity
54 m²/s²
0-3 km storm-relative helicity
286 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

707 
WWUS45 KBOU 141019
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
319 AM MST Wed Feb 14 2018

...DIFFICULT TRAVEL CONDITIONS TONIGHT AND THURSDAY...

.Heavy snow and blowing snow will create difficult travel
conditions tonight and Thursday over the higher mountainous
terrain of North Central Colorado. Snow will begin late this 
afternoon and early evening, and continue overnight and Thursday. 
Snow will be heavy at times, with snowfall rates of 1 to 2 inches 
an hour possible. Travel tonight and Thursday will be impacted,
especially over mountain passes.

COZ031-033-034-141830-
/O.NEW.KBOU.WS.W.0003.180215T0000Z-180216T0100Z/
Rabbit Ears Pass-
Rocky Mountain National Park and the Medicine Bow Range-
The Mountains of Summit County, the Mosquito Range, and the
Indian Peaks-
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, Willow Creek Pass, 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
319 AM MST Wed Feb 14 2018

...WINTER STORM WARNING IN EFFECT FROM 5 PM THIS AFTERNOON TO
6 PM MST THURSDAY...

* WHAT...Heavy snow and blowing snow expected. Total snow 
  accumulations of 6 to 10 inches, with localized amounts up to 
  14 inches, are expected.

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

* WHEN...From 5 PM this afternoon to 6 PM MST Thursday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions. 
  Winds gusting as high as 60 mph will cause areas of blowing 
  and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions will make travel very hazardous or
impossible. 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.

&&

$$

Hanson
5 follow-up statements
016 
WWUS45 KBOU 141719
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
1019 AM MST Wed Feb 14 2018

...DIFFICULT TRAVEL CONDITIONS TONIGHT AND THURSDAY...

.Heavy snow and strong winds will create difficult travel 
conditions tonight and Thursday over the higher mountainous 
terrain of North Central Colorado. Snow will begin late this 
afternoon and early evening over the northern mountains, spreading
southward over the I-70 corridor after midnight and continuing 
overnight and Thursday. Snow will be heavy at times, with snowfall
rates of 1 to 2 inches an hour possible. Strong winds up to 60 mph will create
low visibility in blowing snow. Travel tonight and Thursday will 
be impacted, especially over mountain passes.

COZ034-150200-
/O.EXT.KBOU.WS.W.0003.180215T0700Z-180216T0100Z/
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
1019 AM MST Wed Feb 14 2018

...WINTER STORM WARNING NOW IN EFFECT FROM MIDNIGHT TONIGHT TO
6 PM MST THURSDAY...

* WHAT...Heavy snow and blowing snow expected. Total snow
  accumulations of 4 to 8 inches, with localized amounts up to 10
  inches, are expected.

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

* WHEN...From midnight tonight to 6 PM MST Thursday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions. Winds
  gusting as high as 60 mph will cause low visibility in areas of
  blowing and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions will make travel very hazardous or
impossible. 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.

&&

$$

COZ031-033-150200-
/O.CON.KBOU.WS.W.0003.180215T0000Z-180216T0100Z/
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
1019 AM MST Wed Feb 14 2018

...WINTER STORM WARNING REMAINS IN EFFECT FROM 5 PM THIS
AFTERNOON TO 6 PM MST THURSDAY...

* WHAT...Heavy snow and blowing snow expected. Total snow 
  accumulations of 6 to 10 inches, with localized amounts up to 
  15 inches, are expected.

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

* WHEN...From 5 PM this afternoon to 6 PM MST Thursday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions. Winds
  gusting as high as 60 mph will cause low visibility in areas of
  blowing and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions will make travel very hazardous or
impossible. 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.

&&

$$
828 
WWUS45 KBOU 142256
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
356 PM MST Wed Feb 14 2018

...DIFFICULT TRAVEL CONDITIONS TONIGHT AND THURSDAY...

.Heavy snow and strong winds will create difficult travel
conditions tonight and Thursday over the higher mountainous
terrain of North Central Colorado. Snow will begin this evening 
over the northern mountains, spreading southward over the I-70 
corridor after midnight and continue on Thursday. Snow will be 
heavy at times, with snowfall rates of 1 to 2 inches an hour 
possible. Strong winds up to 60 mph will create low visibility in 
blowing snow. Travel tonight and Thursday will be impacted, 
especially over mountain passes.

COZ031-033-150700-
/O.CON.KBOU.WS.W.0003.180215T0000Z-180216T0100Z/
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
356 PM MST Wed Feb 14 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MST
THURSDAY...

* WHAT...Heavy snow and blowing snow expected. Total snow
  accumulations of 6 to 12 inches, with localized amounts up to 16 
  inches, are expected.

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

* WHEN...Until 6 PM MST Thursday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions. 
  Winds gusting as high as 55 mph will cause areas of blowing 
  and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions will make travel very hazardous or
impossible. 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.

&&

$$

COZ034-150700-
/O.CON.KBOU.WS.W.0003.180215T0700Z-180216T0100Z/
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
356 PM MST Wed Feb 14 2018

...WINTER STORM WARNING REMAINS IN EFFECT FROM MIDNIGHT TONIGHT
TO 6 PM MST THURSDAY...

* WHAT...Heavy snow and blowing snow expected. Total snow
  accumulations of 5 to 10 inches, with localized amounts up to 14
  inches, are expected.

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

* WHEN...From midnight tonight to 6 PM MST Thursday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions, 
  including during the morning commute on Thursday. Winds 
  gusting as high as 55 mph will cause areas of blowing and 
  drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions will make travel very hazardous or
impossible. 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.

&&

$$
442 
WWUS45 KBOU 150448
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
948 PM MST Wed Feb 14 2018

...DIFFICULT TRAVEL CONDITIONS OVERNIGHT INTO THURSDAY...

.Heavy snow and strong winds will create difficult travel
conditions later tonight and Thursday over the higher mountainous
terrain of North Central Colorado. Snow will increase overnight 
in the mountains and continue on Thursday. Snow will be heavy at 
times, with snowfall rates of 1 to 2 inches an hour possible. 
Strong winds up to 60 mph will create low visibility in blowing 
snow. Travel overnight and Thursday will be impacted, especially 
over mountain passes.

COZ031-033-151300-
/O.CON.KBOU.WS.W.0003.000000T0000Z-180216T0100Z/
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
948 PM MST Wed Feb 14 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MST
THURSDAY...

* WHAT...Heavy snow and blowing snow expected. Total snow
  accumulations of 6 to 12 inches, with localized amounts up to 16 
  inches, are expected.

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

* WHEN...Until 6 PM MST Thursday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions. Winds
  gusting as high as 55 mph will cause areas of blowing and 
  drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions will make travel very hazardous or
impossible. 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.

&&

$$

COZ034-151300-
/O.CON.KBOU.WS.W.0003.180215T0700Z-180216T0100Z/
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
948 PM MST Wed Feb 14 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MST
THURSDAY...

* WHAT...Heavy snow and blowing snow expected. Total snow
  accumulations of 5 to 10 inches, with localized amounts up to 14
  inches, are expected.

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

* WHEN...Until 6 PM MST Thursday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions, 
  including during the morning commute on Thursday. Winds 
  gusting as high as 55 mph will cause areas of blowing and 
  drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions will make travel very hazardous or
impossible. 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.

&&

$$
229 
WWUS45 KBOU 151203
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
503 AM MST Thu Feb 15 2018

...DIFFICULT TRAVEL CONDITIONS IN THE MOUNTAINS TODAY...

.Heavy snow and strong winds will create difficult travel
conditions through this evening over the higher mountainous 
terrain of North Central Colorado. Snow will be heavy at times, 
with snowfall rates of 1 to 2 inches an hour possible. Strong 
winds up to 50 mph will create low visibility in blowing snow. 
Travel today will be impacted, especially over mountain passes.

COZ031-033-152215-
/O.CON.KBOU.WS.W.0003.000000T0000Z-180216T0100Z/
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
503 AM MST Thu Feb 15 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MST THIS
EVENING...

* WHAT...Heavy snow and blowing snow. Additional snow 
  accumulations of 4 to 8 inches are expected.

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

* WHEN...Until 6 PM MST this evening.

* ADDITIONAL DETAILS...Plan on difficult travel conditions. 
  Winds gusting as high as 40 mph will cause areas of blowing 
  and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions will make travel very hazardous or
impossible. 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.

&&

$$

COZ034-152215-
/O.CON.KBOU.WS.W.0003.000000T0000Z-180216T0100Z/
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
503 AM MST Thu Feb 15 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MST THIS
EVENING...

* WHAT...Heavy snow and blowing snow. Additional snow 
  accumulations of 4 to 8 inches are expected.

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

* WHEN...Until 6 PM MST this evening.

* ADDITIONAL DETAILS...Plan on difficult travel conditions. Winds
  gusting as high as 50 mph will cause areas of blowing and 
  drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions will make travel very hazardous or
impossible. 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.

&&

$$
793 
WWUS45 KBOU 151837
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
1137 AM MST Thu Feb 15 2018

...HAZARDOUS TRAVEL CONDITIONS IN THE MOUNTAINS THROUGH EARLY
EVENING...

.Snow, heavy at times, and gusty winds will create hazardous 
travel conditions across the Colorado mountains through early this
evening. Snowfall rates in the heavier snow showers will range
between 1 and 2 inch per hour. Some of this heavier snow will 
spread across the I-70 Mountain Corridor between Vail Pass and the
Eisenhower Tunnel this afternoon. Then snow will gradually
decrease across the northern mountains this evening. Travelers
into the Colorado high country should be prepared for hazardous
winter travel and possible travel restrictions. 

COZ031-033-160100-
/O.CON.KBOU.WS.W.0003.000000T0000Z-180216T0100Z/
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
1137 AM MST Thu Feb 15 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MST THIS
EVENING...

* WHAT...Snow, heavy at times, and blowing snow. Additional snow
  accumulations of 1 to 4 inches are expected.

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

* WHEN...Until 6 PM MST this evening.

* ADDITIONAL DETAILS...Plan on difficult travel conditions, 
  including during the evening commute. Winds gusting as high as 
  40 mph will cause areas of blowing and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions will make travel very hazardous or
impossible. 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.

&&

$$

COZ034-160100-
/O.CON.KBOU.WS.W.0003.000000T0000Z-180216T0100Z/
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
1137 AM MST Thu Feb 15 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MST THIS
EVENING...

* WHAT...Snow, heavy at times, and blowing snow. Additional snow 
  accumulations of 2 to 4 inches are expected.

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

* WHEN...Until 6 PM MST this evening.

* ADDITIONAL DETAILS...Plan on difficult travel conditions, 
  including during the evening commute. Winds gusting as high as 
  40 mph will cause areas of blowing and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions will make travel very hazardous or
impossible. 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.

&&

$$

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 13, 8:50 PM MST, 6 hours 29 minutes earlier.

Area forecast discussion, Feb 13, 8:50 PM MST, 6 hours 29 minutes before
Area Forecast Discussion
National Weather Service Denver/Boulder CO
850 PM MST Tue Feb 13 2018

.UPDATE...
Issued at 850 PM MST Tue Feb 13 2018

Only minor adjustments to the gridded forecast package this
evening. An upper jet moving over the state from the south tonight
and tomorrow will increase the flow over the state. An amplified
mountain wave is forecast to develop which will produce gusty
winds in and near the foothills. The mountain wave structure is
expected to remain in place through the day tomorrow, producing
the gusty winds into tomorrow evening. Peak gusts could be in the
40 to 50 mph range, strongest from about 6 AM through 2 PM. Areas
west of I-25 along with the foothill areas of Larimer County will
see the strongest winds. Temperatures tomorrow will be warmer
again due to warm advection from the westerly flow.

The other thing we will be keeping an eye on is the expected snow
in the mountains tomorrow night through Thursday. At that time,
moisture will be increasing from the northwest as the entrance
region of the upper jet linger over the state. Will not issue any
highlights at this time, but a decent shot of snow sure looks to
be in store. No other changes to the forecast at this time.

&&

.SHORT TERM...(This evening through Wednesday)
Issued at 1219 PM MST Tue Feb 13 2018

The upper low that was over the SW has continued to retrograde
into the Pacific with increasing SW flow over the state. Light
snow over the northern mountains will be light with lingering
moisture and orographics providing for light snow through the
day. At lower elevations temperatures will be warmer than the
last few days with highs reaching into the mid 50s. A 120+ kt jet
streak will make its way NE and into central Colorado overnight
greatly increasing SW flow over the mountains and plains. Speeds
will gradually increase in the mountains through the early morning
hours. Model cross sections are not showing much amplification or
stable layer so do not expect winds to make it too far east on
the plains but lower foothills out to BJC could gust into the 30s
and low 40s at times during the morning hours. Winds will increase
however over the far eastern plains with the possibly of light
gusting and sustained winds of 12 to 15 mph. RH levels are in the
low 20s with decent fuel moisture provided by snow but winds and
temperatures reaching into the low 60s for Wednesday will increase
fire weather concerns for drier areas.

.LONG TERM...(Wednesday night through Tuesday)
Issued at 1219 PM MST Tue Feb 13 2018

For Wednesday night through late Thursday, the next upper level
disturbance will move across Colorado with more widespread
snowfall developing again for the mountains during late Wednesday
night and Thursday. With still a fair amount of wind could see
advisory amounts, especially over zone 31 and 33. An associated
cold front will mover the plains Thursday morning with colder
temperatures expected. Moisture looks rather limited so will only
have a slight chance of snow expected mainly in the afternoon
with increased instability.

Following the upper trof on Thursday, Colorado will transition to
a drier northwest flow pattern for Friday and Saturday. Still
chilly on Friday but warmer on Saturday. Flow aloft shifts back
west and southwest by late Saturday and Sunday as next stronger
system drops in the Great Basin. This system could effect Colorado
in the late Sunday through almost the middle of next week. There
are considerable model differences in the handling of the
amplification and timing with the incoming wave. The European
solution is quicker with the main trof position closer to Colorado
with higher chances of precip as early as Sunday evening for the
mountains and on the plains by Monday. The GFS is slower and
doesn't even bring snow in the mountains until early Tuesday
morning. This GFS solution is much slower than the runs from
yesterday and ensemble data is quite varied. The Canadian run is
even displaced further West. Bottom line, confidence is low on
any one solution, and will keep pops chances on the low side and
broad brush through early next week. The big contrast is in
temperatures where the European solution has a high at Denver of
14, while the GFS has a high of 55 for Monday. Yikes.

&&

.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 850 PM MST Tue Feb 13 2018

VFR conditions will prevail through the period as ceilings and
visibilities will not be an issue. The main impact affecting
operations will be the gusty winds forecast late tonight through
tomorrow evening. BJC will see the gustiest winds and for the
longest period as sustained winds of 20 to 34 knots are forecast
with wind gusts up to 46 knots between 12 and 20Z. Have increased
the winds at DEN and APA due to growing confidence that winds will
gust to 24 knots during the late morning and early afternoon as a
lee trough will be strengthening. Winds will begin to decrease late
tomorrow afternoon as the boundary layer begins to decouple.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&

UPDATE...Dankers
SHORT TERM...Bowen
LONG TERM...Entrekin
AVIATION...Danielson
Hazardous weather outlook, Feb 13, 10:31 AM MST, 16 hours 48 minutes before
Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1031 AM MST Tue Feb 13 2018

COZ030>051-141745-
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-
1031 AM MST Tue Feb 13 2018

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

.DAY ONE...Today and Tonight

It will be mostly sunny and warmer across the Interstate 25
corridor and northeast plains by this afternoon. In the mountains,
snow showers will decrease through the morning and be confined
mainly to southwest facing slopes. Strong gusty winds to 60 mph
are expected to develop in the foothills late tonight. Overnight
temperatures will be slightly warmer with lows in the upper 20s.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Gusty winds up to 60 mph will continue into Wednesday across the
higher mountains and foothills. Mountain areas are expected to see
a period of snow Wednesday night and Thursday. Light snow may
spread onto the plains Thursday. After a dry period Friday and
through the weekend, the next Pacific system may bring snow to
the region by Monday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight.

Nearby

Winter Storm Warnings in Colorado, 2018Every winter storm warning in 2018

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.