Alert archive / Colorado / Winter Storm Warnings in 2021

Winter Storm Warning 2, NWS Denver/Boulder, CO

February 4, 2021Grand County, Jackson County, Colorado

NWS Denver/Boulder, CO issued this winter storm warning at Feb 4, 2021, 3:30 AM MST for Grand County, Jackson County, Colorado. It took effect at Feb 4, 2021, 5:00 PM MST. It was in force for 36 hr. 4 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 4, 2021, 3:30 AM MST (10:30 UTC)
In effect from
Feb 4, 2021, 5:00 PM MST
Expired
Feb 6, 2021, 5:00 AM MST
In force
36 hr
Issued by
NWS Denver/Boulder, CO

Counties Grand County, CO, Jackson County, CO

The radar

The Cheyenne radar (KCYS), 147 km from the middle of the area, began a volume at 10:35 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 5, 7:00 AM MSTSNOW 2.12 Ssw Elkdale, COCOCORAHS STATION CO-GR-68 TABERNASH 2.7 NW.
Feb 5, 7:00 AM MSTSNOW 52 Ssw Fraser, CO
Feb 5, 8:00 AM MSTSNOW 91 Nne Rabbit Ears Pass, COCOLUMBINE SNOTEL: ESTIMATED USING A 15 TO 1 SNOW TO LIQUID RATIO.
Feb 5, 8:00 AM MSTSNOW 10.511 Nnw Rabbit Ears Pass, COTOWER SNOTEL: ESTIMATED USING A 15 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

Grand Junction, CO (KGJT), launched 00:00Z, 10.5 hours before the alert went out and 239 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, Grand Junction, CO at 00:00Z on 2021-02-04Temperature 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, Grand Junction, CO at 00:00Z on 2021-02-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -47 square meters per square second.1939587897117136156175Sfc1 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
1056 m above ground
0-6 km bulk shear
70 kt
0-1 km storm-relative helicity
-47 m²/s²
0-3 km storm-relative helicity
-13 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

559 
WWUS45 KBOU 041030
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
330 AM MST Thu Feb 4 2021

COZ031-041830-
/O.NEW.KBOU.WS.W.0002.210205T0000Z-210206T1200Z/
/O.CON.KBOU.WW.Y.0005.000000T0000Z-210204T1600Z/
West Jackson and West Grand Counties Above 9000 Feet-
Including the cities of Mt Zirkel
330 AM MST Thu Feb 4 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 9 AM MST THIS 
MORNING...
...WINTER STORM WARNING IN EFFECT FROM 5 PM THIS AFTERNOON TO 5 AM 
MST SATURDAY...

* WHAT...Snow and blowing snow decreasing this morning. The snow and 
  wind will increase again tonight and continue through Friday 
  night.  The snow may be heavy at times on Friday.  Total new snow 
  accumulations of 10 to 18 inches by late Friday night. Winds 
  gusting up to 50 mph.

* WHERE...Rabbit Ears Pass.

* WHEN...For the Winter Storm Warning, from 5 PM this afternoon to 5 
  AM MST Saturday. For the Winter Weather Advisory, until 9 AM MST 
  this morning.

* IMPACTS...Travel could be very difficult late tonight through 
  Friday night.  Visibilities may drop below 1/4 mile due to falling 
  and blowing snow.

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.

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.

&&

$$

COZ034-041500-
/O.CON.KBOU.WS.W.0001.000000T0000Z-210204T1500Z/
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 Indian Peaks, Eisenhower Tunnel, East
Slopes Southern Gore Range, Mount Evans, East Slopes Mosquito
Range, Breckenridge, Winter Park, Williams Fork Mountains,
Kenosha Mountains, and Berthoud Pass
330 AM MST Thu Feb 4 2021

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

* WHAT...Snow and blowing snow decreasing this morning.  Additional 
  snow accumulations of 1 to 2 inches.

* 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. The hazardous 
  conditions could impact this mornings 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.

&&

$$

COZ033-041600-
/O.CON.KBOU.WW.Y.0005.000000T0000Z-210204T1600Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-
Including the cities of Laramie and Medicine Bow Mountains,
Rabbit Ears Range, Cameron Pass, Rocky Mountain National Park,
and Willow Creek Pass
330 AM MST Thu Feb 4 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 9 AM MST THIS 
MORNING...

* WHAT...Snow and blowing snow decreasing this morning. Additional 
  accumulations of 1 to 2 inches.  Winds gusting up to 50 mph.

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

* WHEN...Until 9 AM MST this morning.

* IMPACTS...Plan on slippery road conditions. The hazardous 
  conditions could impact this mornings 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.

&&

$$

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

RPK
7 follow-up statements
183 
WWUS45 KBOU 041458
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
758 AM MST Thu Feb 4 2021

COZ034-041600-
/O.EXP.KBOU.WS.W.0001.000000T0000Z-210204T1500Z/
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 Indian Peaks, Eisenhower Tunnel, East
Slopes Southern Gore Range, Mount Evans, East Slopes Mosquito
Range, Breckenridge, Winter Park, Williams Fork Mountains,
Kenosha Mountains, and Berthoud Pass
758 AM MST Thu Feb 4 2021

...WINTER STORM WARNING WILL EXPIRE AT 8 AM MST THIS MORNING...

Road conditions should generally improve during the day, though 
exposed higher areas will continue to have areas of blowing and 
drifting snow.

$$

COZ031-042300-
/O.CAN.KBOU.WW.Y.0005.000000T0000Z-210204T1600Z/
/O.CON.KBOU.WS.W.0002.210205T0000Z-210206T1200Z/
West Jackson and West Grand Counties Above 9000 Feet-
Including the cities of Mt Zirkel
758 AM MST Thu Feb 4 2021

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

* WHAT...Only light snow is expected today. The snow and wind will 
  increase again tonight and continue through Friday night.  The 
  snow may be heavy at times on Friday.  Total new snow 
  accumulations of 10 to 18 inches are expected by late Friday 
  night, with winds gusting up to 50 mph.

* WHERE...Rabbit Ears Pass.

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

* IMPACTS...Travel could be very difficult to impossible on Friday 
  and Friday night. Visibilities may drop below 1/4 mile due to 
  falling and blowing snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Consider traveling over Rabbit Ears Pass today while conditions are 
better, or taking alternate routes. If you must travel during the 
storm, bring 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.

&&

$$

COZ033-041600-
/O.CAN.KBOU.WW.Y.0005.000000T0000Z-210204T1600Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-
Including the cities of Laramie and Medicine Bow Mountains,
Rabbit Ears Range, Cameron Pass, Rocky Mountain National Park,
and Willow Creek Pass
758 AM MST Thu Feb 4 2021

...WINTER WEATHER ADVISORY IS CANCELLED...

Any snow today will be very light, though there will still be areas 
of blowing and drifting snow in exposed higher areas. Road 
conditions should generally improve during the day.

$$

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

Gimmestad
695 
WWUS45 KBOU 042139
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
239 PM MST Thu Feb 4 2021

COZ031-051200-
/O.CON.KBOU.WS.W.0002.210205T0000Z-210206T1200Z/
West Jackson and West Grand Counties Above 9000 Feet-
Including the cities of Mt Zirkel
239 PM MST Thu Feb 4 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM MST SATURDAY...

* WHAT...Snow and wind will increase again tonight and continue 
  through Friday night.  The snow may be heavy at times on Friday 
  and Friday night.  Total new snow accumulations of 10 to 18 inches 
  are expected by late Friday night, with even heavier amounts 
  possible above timberline.
  Winds will gust up to 50 mph producing near blizzard conditions in 
  blowing and drifting snow.

* WHERE...Rabbit Ears Pass.

* WHEN...Until 5 AM MST Saturday.

* IMPACTS...Travel could be very difficult to impossible Friday 
  afternoon and Friday night. Consider traveling before conditions 
  deteriorate or taking another route.

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 can 
be obtained by calling 5 1 1 or visiting www.cotrip.org.

&&

$$

COZ033-034-051200-
/O.NEW.KBOU.WW.Y.0006.210204T2139Z-210206T1200Z/
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
239 PM MST Thu Feb 4 2021

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 5 AM MST SATURDAY...

* WHAT...Winds gusting as high as 65 mph will produce extensive 
  blowing and drifting snow with near blizzard conditions at times 
  in exposed areas. Periods of light snowfall through Friday 
  morning, then steadier snow Friday afternoon and evening. 
  Additional snow through Friday night will be 4 to 10 inches in the 
  higher mountains, with lighter amounts in the valleys.

* 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 5 AM MST Saturday.

* IMPACTS...Travel could be very difficult, especially over Loveland 
  and Berthoud Passes and along US 285 in South Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

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

Gimmestad/Direnzo
735 
WWUS45 KBOU 051001
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
301 AM MST Fri Feb 5 2021

COZ031-051815-
/O.CON.KBOU.WS.W.0002.000000T0000Z-210206T1200Z/
West Jackson and West Grand Counties Above 9000 Feet-
Including the cities of Mt Zirkel
301 AM MST Fri Feb 5 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM MST SATURDAY...

* WHAT...Snow and wind will increase today and continue through 
  tonight.  The snow may be heavy at times.  Total new snow 
  accumulations of 10 to 18 inches are expected by late tonight, 
  with even heavier amounts possible above timberline. Winds will 
  gust up to 50 mph producing near blizzard conditions in blowing 
  and drifting snow.

* WHERE...Rabbit Ears Pass.

* WHEN...Until 5 AM MST Saturday.

* IMPACTS...Travel could be very difficult to impossible. The 
  hazardous conditions could impact the morning and evening 
  commutes. Visibilities may drop below 1/4 mile due to falling and 
  blowing snow.

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.

&&

$$

COZ033-034-051815-
/O.CON.KBOU.WW.Y.0006.000000T0000Z-210206T1200Z/
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
301 AM MST Fri Feb 5 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 AM MST 
SATURDAY...

* WHAT...Winds gusting as high as 65 mph will produce extensive 
  blowing and drifting snow with near blizzard conditions at times 
  in exposed areas. Periods of light snowfall this morning, then 
  steadier snow this afternoon and evening. Additional snow through 
  late tonight will be 4 to 10 inches in the higher mountains, with 
  lighter amounts in the valleys.

* 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 5 AM MST Saturday.

* IMPACTS...Plan on slippery road conditions. The hazardous 
  conditions could impact the morning and evening commutes.

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.

&&

$$

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

RPK
512 
WWUS45 KBOU 051814
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
1114 AM MST Fri Feb 5 2021

COZ031-060400-
/O.CON.KBOU.WS.W.0002.000000T0000Z-210206T1200Z/
West Jackson and West Grand Counties Above 9000 Feet-
Including the cities of Mt Zirkel
1114 AM MST Fri Feb 5 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM MST SATURDAY...

* WHAT...Snow and wind will increase today and continue through 
  tonight.  The snow may be heavy at times.  Total new snow 
  accumulations of 10 to 18 inches are expected by late tonight, 
  with even heavier amounts possible above timberline. Winds will 
  gust up to 50 mph producing near blizzard conditions in blowing 
  and drifting snow.

* WHERE...Rabbit Ears Pass.

* WHEN...Until 5 AM MST Saturday.

* IMPACTS...Travel could be very difficult to impossible. The 
  hazardous conditions could impact the Friday evening commute. 
  Visibilities may drop below 1/4 mile due to falling and blowing 
  snow.

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 can 
be obtained by calling 5 1 1 or visiting www.cotrip.org.

&&

$$

COZ033-034-060400-
/O.CON.KBOU.WW.Y.0006.000000T0000Z-210206T1200Z/
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
1114 AM MST Fri Feb 5 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 AM MST 
SATURDAY...

* WHAT...Snow will increase this afternoon and evening. Additional 
  snow accumulations of 4 to 10 inches at higher elevations, with 
  lighter amounts in the valleys. Winds gusting as high as 55 mph 
  will cause extensive blowing and drifting snow.

* 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 5 AM MST Saturday.

* IMPACTS...Travel could be very difficult. Areas of blowing snow 
  could significantly reduce visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

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

Gimmestad
939 
WWUS45 KBOU 060358
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
858 PM MST Fri Feb 5 2021

COZ031-061200-
/O.CON.KBOU.WS.W.0002.000000T0000Z-210206T1200Z/
West Jackson and West Grand Counties Above 9000 Feet-
Including the cities of Mt Zirkel
858 PM MST Fri Feb 5 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM MST SATURDAY...

* WHAT...Snow will continue tonight. Additional snow accumulations 
  of 1 to 5 inches are expected by 5 AM Saturday morning, with even 
  heavier amounts possible above timberline. Winds will gust up to 
  50 mph producing near blizzard conditions in blowing and drifting 
  snow.

* WHERE...Rabbit Ears Pass.

* WHEN...Until 5 AM MST Saturday.

* IMPACTS...Plan on slippery road conditions. Areas of blowing snow 
  could significantly reduce visibility. Gusty winds could bring 
  down tree branches. Visibilities may drop below 1/4 mile due to 
  falling and blowing snow.

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.

Persons should consider delaying all travel. If travel is absolutely 
necessary, drive with extreme caution. Consider taking a winter 
storm kit along with you, including such items as tire chains, 
booster cables, flashlight, shovel, blankets and extra clothing. 
Also take water, a first aid kit, and anything else that would help 
you survive in case you become stranded.

&&

$$

COZ033-034-061200-
/O.CON.KBOU.WW.Y.0006.000000T0000Z-210206T1200Z/
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
858 PM MST Fri Feb 5 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 AM MST 
SATURDAY...

* WHAT...Snow will continue overnight. Additional snow accumulations 
  of 1 to 3  inches are expected through 5 AM Saturday morning, with 
  lighter amounts in the valleys. Winds gusting as high as 55 mph 
  will cause extensive blowing and drifting snow.

* 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 5 AM MST Saturday.

* IMPACTS...Plan on slippery road conditions. Areas of blowing snow 
  could significantly reduce visibility. Extensive damage to trees 
  and power lines is possible.

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.

&&

$$

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

RJK
189 
WWUS45 KBOU 061042
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
342 AM MST Sat Feb 6 2021

COZ031-061845-
/O.NEW.KBOU.WW.Y.0007.210207T0000Z-210207T1200Z/
/O.CON.KBOU.WS.W.0002.000000T0000Z-210206T1200Z/
West Jackson and West Grand Counties Above 9000 Feet-
Including the cities of Mt Zirkel
342 AM MST Sat Feb 6 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM MST EARLY THIS 
MORNING...
...WINTER WEATHER ADVISORY IN EFFECT FROM 5 PM THIS AFTERNOON TO 5 
AM MST SUNDAY...

* WHAT...Snow will gradually decrease this morning. Additional snow 
  accumulations of 1 to 3 inches may occur today. Winds will gust up 
  to 40 mph producing blowing and drifting snow.  Snow will then 
  increase again this evening and continue overnight with additional 
  accumulations of 5 to 10 inches.  Winds will gust to 50 mph at 
  times with near blizzard conditions in blowing snow.

* WHERE...Rabbit Ears Pass.

* WHEN...For the Winter Weather Advisory, from 5 PM this afternoon 
  to 5 AM MST Sunday. For the Winter Storm Warning, until 5 AM MST 
  early this morning.

* IMPACTS...Travel could be very difficult. Areas of blowing snow 
  could significantly reduce visibility. Visibilities may drop below 
  1/4 mile due to falling and blowing snow.

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.


&&

$$

COZ033-061845-
/O.NEW.KBOU.WW.Y.0007.210207T0000Z-210207T1200Z/
/O.CON.KBOU.WW.Y.0006.000000T0000Z-210206T1200Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-
Including the cities of Laramie and Medicine Bow Mountains,
Rabbit Ears Range, Cameron Pass, Rocky Mountain National Park,
and Willow Creek Pass
342 AM MST Sat Feb 6 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 AM MST EARLY 
THIS MORNING...
...WINTER WEATHER ADVISORY IN EFFECT FROM 5 PM THIS AFTERNOON TO 5 
AM MST SUNDAY...

* WHAT...Snow will decrease morning. Additional snow accumulations 
  of 1 to 3  inches are expected today. Winds gusting as high as 50 
  mph will cause blowing and drifting snow.  Snow will then increase 
  this evening and continue overnight.  Additional accumulations of 
  4 to 8 inches will be possible.  Winds gusting to 70 mph will 
  produce near blizzard conditions in blowing snow.

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

* WHEN...For the first Winter Weather Advisory, from 5 PM this 
  afternoon to 5 AM MST Sunday. For the second Winter Weather 
  Advisory, until 5 AM MST early this morning.

* IMPACTS...Plan on slippery road conditions. Widespread blowing 
  snow could significantly reduce visibility with very difficult 
  travel conditions.

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.

&&

$$

COZ034-061200-
/O.CON.KBOU.WW.Y.0006.000000T0000Z-210206T1200Z/
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 Indian Peaks, Eisenhower Tunnel, East
Slopes Southern Gore Range, Mount Evans, East Slopes Mosquito
Range, Breckenridge, Winter Park, Williams Fork Mountains,
Kenosha Mountains, and Berthoud Pass
342 AM MST Sat Feb 6 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 AM MST EARLY 
THIS MORNING...

* WHAT...Snow will decrease this morning. Additional snow 
  accumulations of 1 to 2 inches are expected today. Winds gusting 
  as high as 50 mph will cause blowing and drifting snow over the 
  higher mountain passes early this morning.

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

* WHEN...Until 5 AM MST early this morning.

* IMPACTS...Plan on slippery road conditions. Blowing snow could 
  significantly reduce visibility early this morning.

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.

&&

$$

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

RPK
143 
WWUS45 KBOU 061207
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
507 AM MST Sat Feb 6 2021

COZ031-062015-
/O.EXP.KBOU.WS.W.0002.000000T0000Z-210206T1200Z/
/O.CON.KBOU.WW.Y.0007.210207T0000Z-210207T1200Z/
West Jackson and West Grand Counties Above 9000 Feet-
Including the cities of Mt Zirkel
507 AM MST Sat Feb 6 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 5 PM THIS 
AFTERNOON TO 5 AM MST SUNDAY...
...WINTER STORM WARNING HAS EXPIRED...

* WHAT...Snow will gradually decrease this morning. Additional snow 
  accumulations of 1 to 3 inches may occur today. Winds will gust up 
  to 40 mph producing blowing and drifting snow.  Snow will then 
  increase again this evening and continue overnight with additional 
  accumulations of 5 to 10 inches.  Winds will gust to 50 mph at 
  times with near blizzard conditions in blowing snow.

* WHERE...Rabbit Ears Pass.

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

* IMPACTS...Travel could be very difficult tonight. Areas of blowing 
  snow could significantly reduce visibility.

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.

&&

$$

COZ033-062015-
/O.EXP.KBOU.WW.Y.0006.000000T0000Z-210206T1200Z/
/O.CON.KBOU.WW.Y.0007.210207T0000Z-210207T1200Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-
Including the cities of Laramie and Medicine Bow Mountains,
Rabbit Ears Range, Cameron Pass, Rocky Mountain National Park,
and Willow Creek Pass
507 AM MST Sat Feb 6 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 5 PM THIS 
AFTERNOON TO 5 AM MST SUNDAY...
...WINTER WEATHER ADVISORY HAS EXPIRED...

* WHAT...Snow will decrease morning. Additional snow accumulations 
  of 1 to 3  inches are expected today. Winds gusting as high as 50 
  mph will cause blowing and drifting snow.  Snow will then increase 
  this evening and continue overnight.  Additional accumulations of 
  4 to 8 inches will be possible.  Winds gusting to 70 mph will 
  produce near blizzard conditions in blowing snow tonight.

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

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

* IMPACTS...Plan on slippery road conditions. Widespread blowing 
  snow could significantly reduce visibility with difficult travel 
  tonight.

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.

&&

$$

COZ034-061315-
/O.EXP.KBOU.WW.Y.0006.000000T0000Z-210206T1200Z/
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 Indian Peaks, Eisenhower Tunnel, East
Slopes Southern Gore Range, Mount Evans, East Slopes Mosquito
Range, Breckenridge, Winter Park, Williams Fork Mountains,
Kenosha Mountains, and Berthoud Pass
507 AM MST Sat Feb 6 2021

...WINTER WEATHER ADVISORY HAS EXPIRED...

Areas of light snow will continue today with an additional 1 to 2 
inches possible.  Wind gusts to 50 mph will produce areas of blowing 
snow over the higher passes.

$$

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

RPK

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 3, 8:44 PM MSTSpecial Weather StatementBOUArapahoe, Douglas, Elbert46 min
Feb 3, 9:38 PM MSTSpecial Weather StatementBOUDouglas, Elbert52 min
Feb 3, 10:39 PM MSTSpecial Weather StatementBOUElbert36 min
Feb 4, 2:39 PM MSTWinter Weather AdvisoryBOUBoulder, Clear Creek, Gilpin, Grand, Jackson, Jefferson and 3 more38 hr

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.