Alert archive / Colorado / High Wind Watches in 2021

High Wind Watch 9, NWS Denver/Boulder, CO

December 28, 20214 counties in Colorado

NWS Denver/Boulder, CO issued this high wind watch at Dec 28, 2021, 1:44 PM MST for 4 counties in Colorado. It took effect at Dec 30, 2021, 5:00 AM MST. It was in force for .

The area

The counties it named.

The facts

Issued
Dec 28, 2021, 1:44 PM MST (20:44 UTC)
In effect from
Dec 30, 2021, 5:00 AM MST
Expired
Dec 29, 2021, 1:36 PM MST
In force
Issued by
NWS Denver/Boulder, CO

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

The radar

The Cheyenne radar (KCYS), 121 km from the middle of the area, began a volume at 20:46 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.

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 8.7 hours before the alert went out and 227 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Denver, CO at 12:00Z on 2021-12-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 12:00Z on 2021-12-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 154 square meters per square second.1939587897Sfc1 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
1393 m above ground
0-6 km bulk shear
58 kt
0-1 km storm-relative helicity
154 m²/s²
0-3 km storm-relative helicity
431 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

726 
WWUS75 KBOU 282044
NPWBOU

URGENT - WEATHER MESSAGE
National Weather Service Denver CO
144 PM MST Tue Dec 28 2021

COZ033-035-290500-
/O.NEW.KBOU.HW.A.0009.211230T1200Z-211231T0600Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-Larimer and
Boulder Counties Between 6000 and 9000 Feet-
Including the cities of Glendevey, Nederland, Rocky Mountain
National Park, Laramie and Medicine Bow Mountains, Red Feather
Lakes, Cameron Pass, Estes Park, Willow Creek Pass, and Rabbit
Ears Range
144 PM MST Tue Dec 28 2021

...HIGH WIND WATCH IN EFFECT FROM LATE WEDNESDAY NIGHT THROUGH 
THURSDAY EVENING...

* WHAT...West winds 25 to 40 mph with gusts to 75 mph possible.

* WHERE...Larimer and Boulder Counties Between 6000 and 9000 Feet 
  and South and East Jackson/Larimer/North and Northeast 
  Grand/Northwest Boulder Counties Above 9000 Feet Counties.

* WHEN...From late Wednesday night through Thursday evening.

* IMPACTS...Damaging winds could blow down trees and power lines. 
  Travel could be difficult, especially for high profile vehicles. 
  Blowing snow may create dangerous driving conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts and warnings for updates.

Winds this strong can make driving difficult, especially for high 
profile vehicles. Use extra caution.

&&

$$

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

Rodriguez
4 follow-up statements
794 
WWUS75 KBOU 290336
NPWBOU

URGENT - WEATHER MESSAGE
National Weather Service Denver CO
836 PM MST Tue Dec 28 2021

COZ033-035-291300-
/O.CON.KBOU.HW.A.0009.211230T1200Z-211231T0600Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-Larimer and
Boulder Counties Between 6000 and 9000 Feet-
Including the cities of Glendevey, Nederland, Rocky Mountain
National Park, Laramie and Medicine Bow Mountains, Red Feather
Lakes, Cameron Pass, Estes Park, Willow Creek Pass, and Rabbit
Ears Range
836 PM MST Tue Dec 28 2021

...HIGH WIND WATCH REMAINS IN EFFECT FROM LATE WEDNESDAY NIGHT 
THROUGH THURSDAY EVENING...

* WHAT...West winds 25 to 40 mph with gusts to 75 mph possible.

* WHERE...Larimer and Boulder Counties Between 6000 and 9000 Feet 
  and South and East Jackson/Larimer/North and Northeast 
  Grand/Northwest Boulder Counties Above 9000 Feet Counties.

* WHEN...From late Wednesday night through Thursday evening.

* IMPACTS...Damaging winds could blow down trees and power lines. 
  Widespread power outages are possible. Travel could be difficult, 
  especially for high profile vehicles.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts and warnings for updates.

Winds this strong can make driving difficult, especially for high 
profile vehicles. Use extra caution.

&&

$$

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

Entrekin
782 
WWUS75 KBOU 291026
NPWBOU

URGENT - WEATHER MESSAGE
National Weather Service Denver CO
326 AM MST Wed Dec 29 2021

COZ033-035-291830-
/O.CON.KBOU.HW.A.0009.211230T1200Z-211231T0600Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-Larimer and
Boulder Counties Between 6000 and 9000 Feet-
Including the cities of Glendevey, Nederland, Rocky Mountain
National Park, Laramie and Medicine Bow Mountains, Red Feather
Lakes, Cameron Pass, Estes Park, Willow Creek Pass, and Rabbit
Ears Range
326 AM MST Wed Dec 29 2021

...HIGH WIND WATCH REMAINS IN EFFECT FROM LATE TONIGHT THROUGH 
THURSDAY EVENING...

* WHAT...West winds 25 to 40 mph with gusts to 75 mph possible.

* WHERE...Larimer and Boulder Counties Between 6000 and 9000 Feet 
  and South and East Jackson/Larimer/North and Northeast 
  Grand/Northwest Boulder Counties Above 9000 Feet Counties.

* WHEN...From late tonight through Thursday evening.

* IMPACTS...Damaging winds could blow down trees and power lines. 
  Widespread power outages are possible. Travel could be difficult, 
  especially for high profile vehicles.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts and warnings for updates.

Winds this strong can make driving difficult, especially for high 
profile vehicles. Use extra caution.

&&

$$

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

RPK
383 
WWUS75 KBOU 291752
NPWBOU

URGENT - WEATHER MESSAGE
National Weather Service Denver CO
1052 AM MST Wed Dec 29 2021

COZ033-035-300800-
/O.CON.KBOU.HW.A.0009.211230T1200Z-211231T0600Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-Larimer and
Boulder Counties Between 6000 and 9000 Feet-
Including the cities of Glendevey, Nederland, Rocky Mountain
National Park, Laramie and Medicine Bow Mountains, Red Feather
Lakes, Cameron Pass, Estes Park, Willow Creek Pass, and Rabbit
Ears Range
1052 AM MST Wed Dec 29 2021

...HIGH WIND WATCH REMAINS IN EFFECT FROM LATE TONIGHT THROUGH 
THURSDAY EVENING...

* WHAT...West winds 25 to 40 mph with gusts to 75 mph possible.

* WHERE...Larimer and Boulder Counties Between 6000 and 9000 Feet 
  and South and East Jackson/Larimer/North and Northeast 
  Grand/Northwest Boulder Counties Above 9000 Feet Counties.

* WHEN...From late tonight through Thursday evening.

* IMPACTS...Damaging winds could blow down trees and power lines. 
  Widespread power outages are possible. Travel could be difficult, 
  especially for high profile vehicles.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts and warnings for updates.

Winds this strong can make driving difficult, especially for high 
profile vehicles. Use extra caution.

&&

$$

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

AD
775 
WWUS75 KBOU 292036
NPWBOU

URGENT - WEATHER MESSAGE
National Weather Service Denver CO
136 PM MST Wed Dec 29 2021

COZ033-035-301800-
/O.UPG.KBOU.HW.A.0009.211230T1200Z-211231T0600Z/
/O.NEW.KBOU.HW.W.0012.211230T1200Z-211231T0600Z/
South and East Jackson/Larimer/North and Northeast
Grand/Northwest Boulder Counties Above 9000 Feet-Larimer and
Boulder Counties Between 6000 and 9000 Feet-
Including the cities of Glendevey, Nederland, Rocky Mountain
National Park, Laramie and Medicine Bow Mountains, Red Feather
Lakes, Cameron Pass, Estes Park, Willow Creek Pass, and Rabbit
Ears Range
136 PM MST Wed Dec 29 2021

...HIGH WIND WARNING IN EFFECT FROM 5 AM TO 11 PM MST THURSDAY...

* WHAT...West winds 25 to 40 mph with gusts to 75 mph possible.

* WHERE...Larimer and Boulder Counties Between 6000 and 9000 Feet 
  and South and East Jackson/Larimer/North and Northeast 
  Grand/Northwest Boulder Counties Above 9000 Feet Counties.

* WHEN...From 5 AM to 11 PM MST Thursday.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected. Travel will be difficult, 
  especially for high profile vehicles.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain in the lower levels of your home during the windstorm, and 
avoid windows. Watch for falling debris and tree limbs. Use caution 
if you must drive.

&&

$$

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

AD

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 28, 1:59 PM MSTWinter Storm WatchBOUBoulder, Clear Creek, Gilpin, Grand, Jackson, Jefferson and 3 more23 hr

Nearby

High Wind Watches in Colorado, 2021Every high wind watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.