Alert archive / Colorado / Winter Storm Warnings in 2022

Winter Storm Warning 13, NWS Denver/Boulder, CO

December 28, 202213 counties in Colorado

NWS Denver/Boulder, CO issued this winter storm warning at Dec 28, 2022, 7:33 PM MST for 13 counties in Colorado. It was in force for 10 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
Dec 28, 2022, 7:33 PM MST (02:33 UTC)
Expired
Dec 29, 2022, 5:40 AM MST
In force
10 hr
Issued by
NWS Denver/Boulder, CO

Counties Adams County, CO, Arapahoe County, CO, Boulder County, CO, Broomfield County, CO, Clear Creek County, CO, Denver County, CO, Douglas County, CO, Elbert County, CO, Gilpin County, CO, Jefferson County, CO, Larimer County, CO, Lincoln County, CO, Park County, CO

The radar

The Denver radar (KFTG), 35 km from the middle of the area, began a volume at 02:34 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
Dec 28, 7:33 PM MSTSNOW 5.51 N Genesee, CO
Dec 28, 8:12 PM MSTSNOW 2.62 Se Boulder, COSNOWFALL RATES CLOSE TO 2 INCHES PER HOUR.
Dec 28, 8:31 PM MSTSNOW 81 N Genesee, CO.
Dec 28, 8:31 PM MSTSNOW 81 N Genesee, CO
Dec 28, 8:41 PM MSTSNOW 1.8Arvada, CO
Dec 28, 8:44 PM MSTSNOW 2.52 S Longmont, CO
Dec 28, 8:51 PM MSTSNOW 3.3Arvada, CO
Dec 28, 8:57 PM MSTSNOW 3.53 S Hygiene, CO
Dec 28, 8:59 PM MSTSNOW 5Conifer, CO.
Dec 28, 8:59 PM MSTSNOW 5Conifer, CO
Dec 28, 9:00 PM MSTSNOW 3.53 E Arvada, CO
Dec 28, 9:01 PM MSTSNOW 5.2Lafayette, CO
Dec 28, 9:05 PM MSTSNOW 91 Sse St Marys Glacier, CO.
Dec 28, 9:05 PM MSTSNOW 91 Sse St Marys Glacier, CO
Dec 28, 9:12 PM MSTSNOW 5.9Broomfield, CO
Dec 28, 9:13 PM MSTSNOW 3Poudre Park, CO.
Dec 28, 9:13 PM MSTSNOW 3Poudre Park, CO
Dec 28, 9:14 PM MSTSNOW 94 Ne Nederland, CO.
Dec 28, 9:14 PM MSTSNOW 94 Ne Nederland, CO
Dec 28, 9:20 PM MSTSNOW 6.5Evergreen, CO
Dec 28, 9:24 PM MSTSNOW 5.51 Nw Erie, CO
Dec 28, 9:30 PM MSTSNOW 92 E Crisman, CO.
Dec 28, 9:30 PM MSTSNOW 92 E Crisman, CO
Dec 28, 9:31 PM MSTSNOW 3.91 E Edgewater, CO
Dec 28, 9:35 PM MSTSNOW 10.81 N Genesee, CO
Dec 28, 9:47 PM MSTSNOW 3.32 N Longmont, CO
Dec 28, 9:52 PM MSTSNOW 5.72 Nw Broomfield, CO2.4 INCHES FELL IN THE LAST HOUR.
Dec 28, 9:56 PM MSTSNOW 62 Sw Rocky Flats, COSPOTTER REPORTED IN CLOUD FLASHES OF LIGHTNING, BUT NO THUNDER HEARD.
Dec 28, 9:58 PM MSTSNOW 141 S Crescent Village, CO.
Dec 28, 9:58 PM MSTSNOW 141 S Crescent Village, CO
Dec 28, 10:00 PM MSTSNOW 52 W Pennock Pass, CO
Dec 28, 10:00 PM MSTHEAVY SNOW 6Louisville, CO2 INCH PER HOUR SNOWFALL RATE.
Dec 28, 10:02 PM MSTSNOW 12.11 N Genesee, CO
Dec 28, 10:03 PM MSTSNOW 5.81 Se Littleton, CO
Dec 28, 10:14 PM MSTSNOW 71 Nw Federal Heights, CO
Dec 28, 10:17 PM MSTHEAVY SNOW 8.32 Nnw Louisville, CO2 INCH PER HOUR SNOWFALL RATES.
Dec 28, 10:26 PM MSTSNOW 8.81 Ne Evergreen, CO
Dec 28, 10:32 PM MSTSNOW 4.81 S Parker, CO
Dec 28, 10:42 PM MSTSNOW 7.21 W Westminster, CO
Dec 28, 10:43 PM MSTSNOW 91 Ne Brookvale, CO.
Dec 28, 10:43 PM MSTSNOW 91 Ne Brookvale, CO
Dec 28, 11:12 PM MSTSNOW 5.53 Ne Longmont, CO
Dec 28, 11:15 PM MSTHEAVY SNOW 5.51 Ese Kassler, CO
Dec 28, 11:19 PM MSTSNOW 122 Sw Rocky Flats, CO.
Dec 28, 11:19 PM MSTSNOW 122 Sw Rocky Flats, CO
Dec 28, 11:23 PM MSTSNOW 6.33 E Arvada, CO
Dec 28, 11:26 PM MSTHEAVY SNOW 102 Nnw Louisville, CO.
Dec 28, 11:26 PM MSTHEAVY SNOW 102 Nnw Louisville, CO
Dec 28, 11:30 PM MSTHEAVY SNOW 81 Ene Westminster, CO.
Dec 28, 11:30 PM MSTHEAVY SNOW 81 Ene Westminster, CO
Dec 28, 11:33 PM MSTHEAVY SNOW 8.2Broomfield, CO
Dec 29, 12:00 AM MSTSNOW 9.71 W Wheat Ridge, CO
Dec 29, 12:05 AM MSTHEAVY SNOW 8.61 Ssw Boulder, CO1 INCH PER HOUR SNOWFALL RATES SINCE 10 PM.
Dec 29, 12:11 AM MSTSNOW 14.22 N Aspen Park, CO
Dec 29, 12:14 AM MSTSNOW 11.5Wah Keeney Park, CO
Dec 29, 12:59 AM MSTSNOW 6.52 E Parker, CO
Dec 29, 1:09 AM MSTSNOW 14.53 S Evergreen, CO
Dec 29, 2:19 AM MSTHEAVY SNOW 11.41 Nnw Louisville, CO
Dec 29, 2:20 AM MSTHEAVY SNOW 9.82 Ssw Boulder, CO
Dec 29, 3:52 AM MSTSNOW 11.51 Nw Ponderosa Park, CO

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, 2.6 hours before the alert went out and 312 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 2022-12-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Grand Junction, CO at 00:00Z on 2022-12-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -56 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
1335 m above ground
0-6 km bulk shear
55 kt
0-1 km storm-relative helicity
-56 m²/s²
0-3 km storm-relative helicity
24 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

136 
WWUS45 KBOU 290233
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
733 PM MST Wed Dec 28 2022

COZ035-291200-
/O.UPG.KBOU.WW.Y.0039.000000T0000Z-221229T1200Z/
/O.NEW.KBOU.WS.W.0013.221229T0233Z-221229T1200Z/
Larimer and Boulder Counties Between 6000 and 9000 Feet-
Including the cities of Estes Park, Glendevey, Red Feather Lakes,
and Nederland
733 PM MST Wed Dec 28 2022

...WINTER STORM WARNING IN EFFECT UNTIL 5 AM MST THURSDAY...

* WHAT...Heavy snow ongoing. Additional snow accumulations up to 4-6 
  inches. Winds gusting as high as 35 mph.

* WHERE...The Northern Front Range Foothills.

* WHEN...Until 5 AM MST Thursday.

* IMPACTS...Roads will likely become slick and hazardous. Heavy snow 
  will accumulate on tree branches and powerlines, possibly causing 
  them to break and lead to power outages. Plan on slippery road 
  conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ036-291200-
/O.UPG.KBOU.WW.Y.0039.000000T0000Z-221229T1200Z/
/O.NEW.KBOU.WS.W.0013.221229T0233Z-221229T1200Z/
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Including the cities of Central City, Evergreen, Bailey,
Georgetown, Westcreek, and Idaho Springs
733 PM MST Wed Dec 28 2022

...WINTER STORM WARNING IN EFFECT UNTIL 5 AM MST THURSDAY...

* WHAT...Heavy snow ongoing. Additional snow accumulations between 3 
  and 6 inches.

* WHERE...The Southern Front Range Foothills.

* WHEN...Until 5 AM MST Thursday.

* IMPACTS...Roads will likely become slick and hazardous. Heavy snow 
  will accumulate on tree branches and powerlines, possibly causing 
  them to break and lead to power outages. Plan on slippery road 
  conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ039-040-291500-
/O.UPG.KBOU.WW.Y.0039.000000T0000Z-221229T1500Z/
/O.NEW.KBOU.WS.W.0013.221229T0233Z-221229T1500Z/
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-
Including the cities of Brighton, Parker, Aurora, Arvada,
Boulder, Littleton, Longmont, Denver International Airport, City
of Denver, Highlands Ranch, Lakewood, and Golden
733 PM MST Wed Dec 28 2022

...WINTER STORM WARNING IN EFFECT UNTIL 8 AM MST THURSDAY...

* WHAT...Heavy snow ongoing. Additional snow accumulations between 3 
  and 6 inches.

* WHERE...Boulder and the western suburbs of Denver, and Denver.

* WHEN...Until 8 AM MST Thursday.

* IMPACTS...Roads will likely become slick and hazardous. Heavy snow 
  will accumulate on tree branches and powerlines, possibly causing 
  them to break and lead to power outages. Plan on slippery road 
  conditions. The hazardous conditions could impact the Thursday 
  morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ041-046-291500-
/O.UPG.KBOU.WW.Y.0039.000000T0000Z-221229T1500Z/
/O.NEW.KBOU.WS.W.0013.221229T0233Z-221229T1500Z/
Elbert/Central and East Douglas Counties Above 6000 Feet-North
and Northeast Elbert County Below 6000 Feet/North Lincoln County-
Including the cities of Castle Rock, Limon, Hugo, Fondis, Elbert,
Agate, Kiowa, Larkspur, and Matheson
733 PM MST Wed Dec 28 2022

...WINTER STORM WARNING IN EFFECT UNTIL 8 AM MST THURSDAY...

* WHAT...Heavy snow ongoing. Additional snow accumulations between 3 
  and 6 inches.

* WHERE...Castle Rock, and Limon.

* WHEN...Until 8 AM MST Thursday.

* IMPACTS...Roads will likely become slick and hazardous. Heavy snow 
  will accumulate on tree branches and powerlines, possibly causing 
  them to break and lead to power outages. Plan on slippery road 
  conditions. The hazardous conditions could impact the Thursday 
  morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ043-044-290345-
/O.EXB.KBOU.WW.Y.0039.000000T0000Z-221229T0300Z/
Central and South Weld County-Morgan County-
Including the cities of Brush, Eaton, Roggen, Fort Lupton,
Goodrich, Wiggins, Fort Morgan, and Greeley
733 PM MST Wed Dec 28 2022

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 8 PM MST THIS EVENING...

* WHAT...Wet snow ongoing. Additional snow accumulations up to 1-3 
  inches.

* WHERE...Greeley, and Fort Morgan.

* WHEN...Until 8 PM MST this evening.

* IMPACTS...Roads will likely become slick and hazardous. Plan on 
  slippery road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ045-290345-
/O.EXT.KBOU.WW.Y.0039.000000T0000Z-221229T0300Z/
Central and East Adams and Arapahoe Counties-
Including the cities of Bennett, Byers, Leader, and Deer Trail
733 PM MST Wed Dec 28 2022

...WINTER WEATHER ADVISORY NOW IN EFFECT UNTIL 8 PM MST THIS 
EVENING...

* WHAT...Wet snow ongoing. Additional snow accumulations up to 2-5 
  inches.

* WHERE...Byers.

* WHEN...Until 8 PM MST this evening.

* IMPACTS...Roads will likely become slick and hazardous. Plan on 
  slippery road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ031-291200-
/O.CON.KBOU.WW.Y.0039.000000T0000Z-221229T1200Z/
West Jackson and West Grand Counties Above 9000 Feet-
Including the cities of Mt Zirkel
733 PM MST Wed Dec 28 2022

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

* WHAT...Snow ongoing. Additional snow accumulations up to 2-4 inch.

* WHERE...Rabbit Ears Pass.

* WHEN...Until 5 AM MST Thursday.

* IMPACTS...Roads will likely become slick and hazardous. Plan on 
  slippery road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ049-291500-
/O.CON.KBOU.WW.Y.0039.000000T0000Z-221229T1500Z/
Washington County-
Including the cities of Last Chance, Cope, Akron, and Otis
733 PM MST Wed Dec 28 2022

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

* WHAT...Snow ongoing. Additional snow accumulations between 1 and 3 
  inches.

* WHERE...Akron.

* WHEN...Until 8 AM MST Thursday.

* IMPACTS...Plan on slippery road conditions. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

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

AD
4 follow-up statements
851 
WWUS45 KBOU 290237
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
737 PM MST Wed Dec 28 2022

COZ035-291200-
/O.CON.KBOU.WS.W.0013.000000T0000Z-221229T1200Z/
Larimer and Boulder Counties Between 6000 and 9000 Feet-
Including the cities of Estes Park, Glendevey, Red Feather Lakes,
and Nederland
737 PM MST Wed Dec 28 2022

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

* WHAT...Heavy snow ongoing. Additional snow accumulations up to 4-6 
  inches. Winds gusting as high as 35 mph.

* WHERE...The Northern Front Range Foothills.

* WHEN...Until 5 AM MST Thursday.

* IMPACTS...Roads will likely become slick and hazardous. Heavy snow 
  will accumulate on tree branches and powerlines, possibly causing 
  them to break and lead to power outages. Plan on slippery road 
  conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ036-291200-
/O.CON.KBOU.WS.W.0013.000000T0000Z-221229T1200Z/
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Including the cities of Central City, Evergreen, Bailey,
Georgetown, Westcreek, and Idaho Springs
737 PM MST Wed Dec 28 2022

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

* WHAT...Heavy snow ongoing. Additional snow accumulations between 3 
  and 6 inches.

* WHERE...The Southern Front Range Foothills.

* WHEN...Until 5 AM MST Thursday.

* IMPACTS...Roads will likely become slick and hazardous. Heavy snow 
  will accumulate on tree branches and powerlines, possibly causing 
  them to break and lead to power outages. Plan on slippery road 
  conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ039-040-291500-
/O.CON.KBOU.WS.W.0013.000000T0000Z-221229T1500Z/
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-
Including the cities of Brighton, Parker, Aurora, Arvada,
Boulder, Littleton, Longmont, Denver International Airport, City
of Denver, Highlands Ranch, Lakewood, and Golden
737 PM MST Wed Dec 28 2022

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

* WHAT...Heavy snow ongoing. Additional snow accumulations between 3 
  and 6 inches.

* WHERE...Boulder and the western suburbs of Denver, and Denver.

* WHEN...Until 8 AM MST Thursday.

* IMPACTS...Roads will likely become slick and hazardous. Heavy snow 
  will accumulate on tree branches and powerlines, possibly causing 
  them to break and lead to power outages. Plan on slippery road 
  conditions. The hazardous conditions could impact the Thursday 
  morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ041-046-291500-
/O.CON.KBOU.WS.W.0013.000000T0000Z-221229T1500Z/
Elbert/Central and East Douglas Counties Above 6000 Feet-North
and Northeast Elbert County Below 6000 Feet/North Lincoln County-
Including the cities of Castle Rock, Limon, Hugo, Fondis, Elbert,
Agate, Kiowa, Larkspur, and Matheson
737 PM MST Wed Dec 28 2022

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

* WHAT...Heavy snow ongoing. Additional snow accumulations between 3 
  and 6 inches.

* WHERE...Castle Rock, and Limon.

* WHEN...Until 8 AM MST Thursday.

* IMPACTS...Roads will likely become slick and hazardous. Heavy snow 
  will accumulate on tree branches and powerlines, possibly causing 
  them to break and lead to power outages. Plan on slippery road 
  conditions. The hazardous conditions could impact the Thursday 
  morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ043>045-291500-
/O.EXT.KBOU.WW.Y.0039.000000T0000Z-221229T1500Z/
Central and South Weld County-Morgan County-Central and East
Adams and Arapahoe Counties-
Including the cities of Bennett, Brush, Eaton, Roggen, Fort
Lupton, Deer Trail, Leader, Goodrich, Byers, Wiggins, Fort
Morgan, and Greeley
737 PM MST Wed Dec 28 2022

...WINTER WEATHER ADVISORY NOW IN EFFECT UNTIL 8 AM MST THURSDAY...

* WHAT...Wet snow ongoing. Additional snow accumulations up to 2-5 
  inches.

* WHERE...Greeley, Fort Morgan, and Byers.

* WHEN...Until 8 AM MST Thursday.

* IMPACTS...Roads will likely become slick and hazardous. Plan on 
  slippery road conditions. The hazardous conditions could impact 
  the Thursday morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ031-291200-
/O.CON.KBOU.WW.Y.0039.000000T0000Z-221229T1200Z/
West Jackson and West Grand Counties Above 9000 Feet-
Including the cities of Mt Zirkel
737 PM MST Wed Dec 28 2022

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

* WHAT...Snow ongoing. Additional snow accumulations up to 2-4 inch.

* WHERE...Rabbit Ears Pass.

* WHEN...Until 5 AM MST Thursday.

* IMPACTS...Roads will likely become slick and hazardous. Travel 
  could be very difficult over the high mountain passes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ049-291500-
/O.CON.KBOU.WW.Y.0039.000000T0000Z-221229T1500Z/
Washington County-
Including the cities of Last Chance, Cope, Akron, and Otis
737 PM MST Wed Dec 28 2022

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

* WHAT...Snow expected. Total snow accumulations between 2 and 5 
  inches.

* WHERE...Akron.

* WHEN...Until 8 AM MST Thursday.

* IMPACTS...Plan on slippery road conditions. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

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

AD
009 
WWUS45 KBOU 291034
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
334 AM MST Thu Dec 29 2022

COZ035-036-291145-
/O.CAN.KBOU.WS.W.0013.000000T0000Z-221229T1200Z/
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-
Including the cities of Westcreek, Idaho Springs, Nederland,
Georgetown, Estes Park, Central City, Glendevey, Red Feather
Lakes, Bailey, and Evergreen
334 AM MST Thu Dec 29 2022

...WINTER STORM WARNING IS CANCELLED...

The threat has ended.

$$

COZ039-291145-
/O.CAN.KBOU.WS.W.0013.000000T0000Z-221229T1500Z/
Boulder And Jefferson Counties Below 6000 Feet/West Broomfield
County-
Including the cities of Longmont, Boulder, Arvada, Lakewood, and
Golden
334 AM MST Thu Dec 29 2022

...WINTER STORM WARNING IS CANCELLED...

$$

COZ031-291145-
/O.CAN.KBOU.WW.Y.0039.000000T0000Z-221229T1200Z/
West Jackson and West Grand Counties Above 9000 Feet-
Including the cities of Mt Zirkel
334 AM MST Thu Dec 29 2022

...WINTER WEATHER ADVISORY IS CANCELLED...

The threat has ended.

$$

COZ040-291500-
/O.CON.KBOU.WS.W.0013.000000T0000Z-221229T1500Z/
North Douglas County Below 6000 Feet/Denver/West Adams and
Arapahoe Counties/East Broomfield County-
Including the cities of Denver International Airport, Parker,
Littleton, City of Denver, Brighton, Highlands Ranch, and Aurora
334 AM MST Thu Dec 29 2022

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

* WHAT...Snow ongoing. Additional snow accumulations up to one inch.

* WHERE...Denver.

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

* IMPACTS...Roads will likely become slick and hazardous. Heavy snow 
  will accumulate on tree branches and powerlines, possibly causing 
  them to break and lead to power outages. Plan on slippery road 
  conditions. The hazardous conditions could impact the Thursday 
  morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ041-046-291500-
/O.CON.KBOU.WS.W.0013.000000T0000Z-221229T1500Z/
Elbert/Central and East Douglas Counties Above 6000 Feet-North
and Northeast Elbert County Below 6000 Feet/North Lincoln County-
Including the cities of Limon, Castle Rock, Matheson, Hugo,
Kiowa, Fondis, Agate, Larkspur, and Elbert
334 AM MST Thu Dec 29 2022

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

* WHAT...Snow ongoing. Additional snow accumulations up to one inch. 
  Winds gusting as high as 35 mph.

* WHERE...Castle Rock, and Limon.

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

* IMPACTS...Roads will likely become slick and hazardous. Heavy snow 
  will accumulate on tree branches and powerlines, possibly causing 
  them to break and lead to power outages. Plan on slippery road 
  conditions. The hazardous conditions could impact the Thursday 
  morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ043>045-291500-
/O.CON.KBOU.WW.Y.0039.000000T0000Z-221229T1500Z/
Central and South Weld County-Morgan County-Central and East
Adams and Arapahoe Counties-
Including the cities of Eaton, Fort Morgan, Goodrich, Fort
Lupton, Wiggins, Brush, Roggen, Bennett, Leader, Greeley, Byers,
and Deer Trail
334 AM MST Thu Dec 29 2022

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

* WHAT...Snow ongoing. Additional snow accumulations up to one inch.

* WHERE...Greeley, Fort Morgan, and Byers.

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

* IMPACTS...Roads will likely become slick and hazardous. Plan on 
  slippery road conditions. The hazardous conditions could impact 
  the Thursday morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ049-291500-
/O.CON.KBOU.WW.Y.0039.000000T0000Z-221229T1500Z/
Washington County-
Including the cities of Otis, Last Chance, Akron, and Cope
334 AM MST Thu Dec 29 2022

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

* WHAT...Snow ongoing. Additional snow accumulations between 1 to 3 
  inches.

* WHERE...Akron.

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

* IMPACTS...Plan on slippery road conditions. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

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

Danielson
937 
WWUS45 KBOU 291131
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
431 AM MST Thu Dec 29 2022

COZ040-291245-
/O.CAN.KBOU.WS.W.0013.000000T0000Z-221229T1500Z/
North Douglas County Below 6000 Feet/Denver/West Adams and
Arapahoe Counties/East Broomfield County-
Including the cities of Denver International Airport, Parker,
Littleton, City of Denver, Brighton, Highlands Ranch, and Aurora
431 AM MST Thu Dec 29 2022

...WINTER STORM WARNING IS CANCELLED...

The threat has ended.

$$

COZ043-291245-
/O.CAN.KBOU.WW.Y.0039.000000T0000Z-221229T1500Z/
Central and South Weld County-
Including the cities of Roggen, Eaton, Fort Lupton, and Greeley
431 AM MST Thu Dec 29 2022

...WINTER WEATHER ADVISORY IS CANCELLED...

$$

COZ041-046-291500-
/O.CON.KBOU.WS.W.0013.000000T0000Z-221229T1500Z/
Elbert/Central and East Douglas Counties Above 6000 Feet-North
and Northeast Elbert County Below 6000 Feet/North Lincoln County-
Including the cities of Limon, Castle Rock, Matheson, Hugo,
Kiowa, Fondis, Agate, Larkspur, and Elbert
431 AM MST Thu Dec 29 2022

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

* WHAT...Heavy snow ongoing. Additional snow accumulations up to one 
  inch.

* WHERE...Castle Rock, and Limon.

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

* IMPACTS...Roads will likely become slick and hazardous. Heavy snow 
  will accumulate on tree branches and powerlines, possibly causing 
  them to break and lead to power outages. Plan on slippery road 
  conditions. The hazardous conditions could impact the Thursday 
  morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ044-045-291500-
/O.CON.KBOU.WW.Y.0039.000000T0000Z-221229T1500Z/
Morgan County-Central and East Adams and Arapahoe Counties-
Including the cities of Fort Morgan, Goodrich, Wiggins, Brush,
Leader, Bennett, Byers, and Deer Trail
431 AM MST Thu Dec 29 2022

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

* WHAT...Snow ongoing. Additional snow accumulations up to one inch.

* WHERE...Fort Morgan, and Byers.

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

* IMPACTS...Roads will likely become slick and hazardous. Plan on 
  slippery road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

COZ049-291500-
/O.CON.KBOU.WW.Y.0039.000000T0000Z-221229T1500Z/
Washington County-
Including the cities of Otis, Last Chance, Akron, and Cope
431 AM MST Thu Dec 29 2022

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

* WHAT...Snow ongoing. Additional snow accumulations between 1 to 3 
  inches.

* WHERE...Akron.

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

* IMPACTS...Plan on slippery road conditions. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

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

Danielson
320 
WWUS45 KBOU 291240
WSWBOU

URGENT - WINTER WEATHER MESSAGE
National Weather Service Denver CO
540 AM MST Thu Dec 29 2022

COZ041-046-291345-
/O.CAN.KBOU.WS.W.0013.000000T0000Z-221229T1500Z/
Elbert/Central and East Douglas Counties Above 6000 Feet-North
and Northeast Elbert County Below 6000 Feet/North Lincoln County-
Including the cities of Limon, Castle Rock, Matheson, Hugo,
Kiowa, Fondis, Agate, Larkspur, and Elbert
540 AM MST Thu Dec 29 2022

...WINTER STORM WARNING IS CANCELLED...

The threat has ended.

$$

COZ044-045-291345-
/O.CAN.KBOU.WW.Y.0039.000000T0000Z-221229T1500Z/
Morgan County-Central and East Adams and Arapahoe Counties-
Including the cities of Fort Morgan, Goodrich, Wiggins, Brush,
Leader, Bennett, Byers, and Deer Trail
540 AM MST Thu Dec 29 2022

...WINTER WEATHER ADVISORY IS CANCELLED...

The threat has ended.

$$

COZ049-291500-
/O.CON.KBOU.WW.Y.0039.000000T0000Z-221229T1500Z/
Washington County-
Including the cities of Otis, Last Chance, Akron, and Cope
540 AM MST Thu Dec 29 2022

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

* WHAT...Snow ongoing. Additional snow accumulations between 1 to 3 
  inches.

* WHERE...Akron.

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

* IMPACTS...Plan on slippery road conditions. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

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

Danielson

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 Dec 28, 4:36 PM MST, 2 hours 57 minutes earlier.

Area forecast discussion, Dec 28, 4:36 PM MST, 2 hours 57 minutes before
Area Forecast Discussion
National Weather Service Denver/Boulder CO
436 PM MST Wed Dec 28 2022

.SHORT TERM...(This evening through Thursday)
Issued at 134 PM MST Wed Dec 28 2022

The latest models continue to produce generous qpf values this
evening. We expanded the winter weather advisory this afternoon to
include Washington County, to better blend with Goodland's highlights.
The best combination of low level upslope and upper level forcing
will be this evening, as the trough axis an the left exit region
of the upper level trough moves over the forecast area. The latest
MRMS data shows a broad area of rain/snow over western CO this afternoon
where the strongest mid/upper level QG ascent is at. This moderate
area of ascent will make its way across the cwa this evening.
Very favorable forcing mechanism in place, but for a fairly brief
period of time, No upgrades planned with the ongoing highlights.
The models keeps the highest QPF south of a line from around
Boulder to DIA to the Palmer Divide this evening, then increasing
subsidence/drying starts to spread west to east after midnight.
Most of the snow will have ended by 5 am but slushy/slick roadways
will likely impact the morning commute. A drier northwesterly
flow will be over the region on Thursday with temperatures
slightly cooler the normal, with highs near 40.

.LONG TERM...(Thursday night through Wednesday)
Issued at 134 PM MST Wed Dec 28 2022

The flow aloft will be WNW from Thu night into Fri as a lee trough
develops at the sfc.  Moisture will increase in the mtns Fri aftn
with a chc of orographic snow. Highs will be in the upper 30s to
mid 40s across the plains.

For Fri night into Sat, the flow aloft will become more westerly.
Cross-sections show favorable moisture and orographics in the
mtns with lapse rates around 6 c/km. As a result should see
periods of snow. Across the plains, it will be dry with warmer
temps as highs reach the 45 to 50 degree range.

Looking ahead to Sat night into Sun, the flow aloft will become more
southwesterly.  Lapse rates and moisture will be favorable for more
snow, mainly in those areas favored by SW flow, which would be
mainly zone 31. Across the plains, there are some differences
between the ECMWF and GFS. The ECMWF has a cold front backing into
nern CO on Sun while the GFS keeps this front further to the
north and northeast. This far out really hard to say which
solution will pan out so will keep highs near seasonal levels for
now.

For Sun night into Mon, there is considerable uncertainty on how an
upper level trough will develop as it moves from the Great
Basin/Swrn US towards the central and srn Rockies. The ECMWF
continues its previous solution of taking most of the energy
further south across the srn Rockies. On the other hand, the
Canadian and GFS models have a more nrn track across the central
Rockies with a strong upper level low developing over ern CO, by
Mon aftn. Naturally a more nrn track would bring a higher
potential for snow to the area versus a more srn track. At this
point it's not clear which solution will win out so have gone with
a blended solution for now.

By Tue, the system will move out of the area with dry conditions and
below normal temps.

&&

.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 429 PM MST Wed Dec 28 2022

Light rain showers are possible through 01Z. Conditions will rapidly
drop to IRF starting 01Z at all terminals where ceiling heights and
visibilities will likely be reduced. Heavy snow banding could occur
during 02-06Z for all terminals where LIFR conditions are also
possible. This upslope flow will keep northerly winds in place
during the heavy snow banding. Under the heavier snow bands,
visibility down to a quarter mile is possible with ceiling heights
as low as 200 feet. Visibilities could improve as early as 13-14Z
at all terminals as this system pushes eastward. Ceiling heights
will increase by late morning and VFR conditions are possible late
Thursday morning through the rest of the TAF period.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 5 AM MST Thursday for COZ031-035-
036.

Winter Weather Advisory until 8 AM MST Thursday for COZ039-040-
045-049.

Winter Weather Advisory until 8 AM MST Thursday for COZ041-046.

&&

SHORT TERM...Cooper
LONG TERM...RPK
AVIATION...AD
Hazardous weather outlook, Dec 28, 9:46 AM MST, 9 hours 47 minutes before
Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
946 AM MST Wed Dec 28 2022

COZ030>051-291700-
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-
946 AM MST Wed Dec 28 2022

...Snow will impact travel in the mountains, southern foothills,
and Palmer Divide today and tonight...

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

.DAY ONE...Today and Tonight

Mountain snow will continue throughout the day today with the
heaviest amounts falling over the western slope of the Park Range.
Lighter snow amounts and lesser travel impacts are expected over the
Front Range mountains. Across the I-25 corridor and plains, rain
will begin this afternoon and will switch over to snow during the
late afternoon or early evening. Snow will then last through much
of the night. The heaviest snowfall totals will likely be over
the Palmer Divide and areas to the east past Limon as well as the
southern foothills. 3-6 inches of snow is most likely in those
areas although amounts up to 8 inches are possible.

There is a lot of uncertainty with regards to snow amounts in the
Denver metro and the northern I-25 corridor because of the
initial rain. Snowfall amounts will range from half an inch to
near 6 inches. The evening rush hour could be impacted especially
south of Denver. I-25 over the Palmer Divide will see hazardous
travel late this afternoon and evening.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

The snow will diminish Thursday morning across the mountains and
Palmer Divide region with only light additional accumulations.

Another storm system will bring another round of snow to the
mountain areas from Friday through the weekend, and the lower
elevations from Sunday afternoon into Monday of next week.
Temperatures will also be colder on Monday across lower
elevations.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight, however
snow reports will be appreciated this afternoon and tonight.

In the hours before

Local storm report, Dec 28, 7:15 PM MST, 18 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
715 PM MST WED DEC 28 2022

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0714 PM     SNOW             2 SE BOULDER            40.00N 105.22W
12/28/2022  E0.8 INCH        BOULDER            CO   TRAINED SPOTTER

&&

JLS
Local storm report, Dec 28, 7:16 PM MST, 17 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
716 PM MST WED DEC 28 2022

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0622 PM     SNOW             1 E HIGHLAND PARK       39.49N 105.51W
12/28/2022  M3.0 INCH        PARK               CO   PUBLIC

0630 PM     SNOW             1 N GENESEE             39.70N 105.28W
12/28/2022  M3.8 INCH        JEFFERSON          CO   PUBLIC

0541 PM     SNOW             4 NE NEDERLAND          39.99N 105.45W
12/28/2022  M1.5 INCH        BOULDER            CO   PUBLIC

&&

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 29, 1:53 PM MSTWinter Storm WarningBOUGrand, Jackson69 hr

Nearby

Winter Storm Warnings in Colorado, 2022Every winter storm warning in 2022

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.