Alert archive / Idaho / Winter Storm Warnings in 2021
Winter Storm Warning 15, NWS Missoula, MT
NWS Missoula, MT issued this winter storm warning at Dec 30, 2021, 7:50 AM PST for Clearwater County, Idaho County, Idaho. It was in force for 11 hr. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Dec 30, 2021, 7:50 AM PST (15:50 UTC)
- Expired
- Dec 30, 2021, 7:00 PM PST
- In force
- 11 hr
- Issued by
- NWS Missoula, MT
Counties Clearwater County, ID, Idaho County, ID
The radar
The Missoula radar (KMSX), 148 km from the middle of the area, began a volume at 15:52 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
Spokane, WA (KOTX), launched 12:00Z, 3.8 hours before the alert went out and 172 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 606 m above ground
- 0-6 km bulk shear
- 84 kt
- 0-1 km storm-relative helicity
- 280 m²/s²
- 0-3 km storm-relative helicity
- 247 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
495
WWUS45 KMSO 301550
WSWMSO
URGENT - WINTER WEATHER MESSAGE
National Weather Service Missoula MT
850 AM MST Thu Dec 30 2021
IDZ007-311600-
/O.UPG.KMSO.WW.Y.0081.000000T0000Z-211231T1800Z/
/O.NEW.KMSO.WS.W.0015.211230T1550Z-211231T0300Z/
/O.NEW.KMSO.WW.Y.0082.211231T0300Z-211231T1800Z/
Orofino/Grangeville Region-
750 AM PST Thu Dec 30 2021
...WINTER STORM WARNING IN EFFECT UNTIL 7 PM PST THIS EVENING...
...WINTER WEATHER ADVISORY IN EFFECT FROM 7 PM THIS EVENING TO
10 AM PST FRIDAY...
* WHAT...For the Winter Storm Warning, snow and blowing snow.
Snow accumulations of 2 to 4 inches.
For the Winter Weather Advisory, snow expected.
Additional snow accumulations of 1 to 3 inches.
* WHERE...Camas Prairie, Grangeville and vicinity, and Greer
Grade.
* WHEN...For the Winter Storm Warning, until 7 PM PST this
evening. For the Winter Weather Advisory, from 7 PM this
evening to 10 AM PST Friday.
* IMPACTS...Travel will be affected. Gusty southerly winds to 35 mph
will produce Blowing Snow which will significantly
reduce visibility to near zero at times.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency.
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.
&&
$$
MTZ002-311600-
/O.CON.KMSO.WW.Y.0081.000000T0000Z-211231T1800Z/
West Glacier Region-
850 AM MST Thu Dec 30 2021
...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST
FRIDAY...
* WHAT...Snow. Additional snow accumulations of 1 to 3 inches.
* WHERE...Bad Rock Canyon, Essex, Highway 83 Bigfork to Swan
Lake, Marias Pass, and Polebridge.
* WHEN...Until 11 AM MST Friday.
* IMPACTS...Travel could be affected. Patchy blowing snow could
significantly reduce visibility. The dangerously cold wind
chills as low as 30 below zero could cause frostbite on
exposed skin in as little as 10 minutes.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Slow down and use caution while traveling.
The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.
&&
$$
MTZ004-311600-
/O.CON.KMSO.WW.Y.0081.000000T0000Z-211231T1800Z/
Lower Clark Fork Region-
850 AM MST Thu Dec 30 2021
...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST
FRIDAY...
* WHAT...Snow. Additional snow accumulations of 1 to 3 inches.
* WHERE...Evaro Hill, Highway 200 Thompson Falls to Plains,
Highway 200 Trout Creek to Heron, and I-90 Lookout Pass to
Haugan.
* WHEN...Until 11 AM MST Friday.
* IMPACTS...Travel could be affected. The cold wind chills as
low as 10 below zero could result in hypothermia if
precautions are not taken.
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.
&&
$$
IDZ005-311600-
/O.CON.KMSO.WW.Y.0081.000000T0000Z-211231T1800Z/
Northern Clearwater Mountains-
750 AM PST Thu Dec 30 2021
...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM PST
FRIDAY...
* WHAT...Snow. Additional snow accumulations of 4 to 6 inches.
* WHERE...Elk River, Highway 11 Pierce to Headquarters, and
Pierce.
* WHEN...Until 10 AM PST Friday.
* IMPACTS...Travel could be affected.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Slow down and use caution while traveling.
The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.
&&
$$
IDZ006-311600-
/O.CON.KMSO.WW.Y.0081.000000T0000Z-211231T1800Z/
Southern Clearwater Mountains-
750 AM PST Thu Dec 30 2021
...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM PST
FRIDAY...
* WHAT...Snow. Additional snow accumulations of 4 to 6 inches.
* WHERE...Dixie, Elk City, and Highway 12 Lowell to Lolo Pass.
* WHEN...Until 10 AM PST Friday.
* IMPACTS...Travel could be affected. The cold wind chills as
low as 10 below zero could result in hypothermia if
precautions are not taken.
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.
&&
$$
IDZ008-311600-
/O.CON.KMSO.WW.Y.0081.000000T0000Z-211231T1800Z/
Lower Hells Canyon/Salmon River Region-
750 AM PST Thu Dec 30 2021
...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM PST
FRIDAY...
* WHAT...Snow. Additional snow accumulations of 4 to 6 inches.
* WHERE...Lower Hells Canyon/Salmon River Region.
* WHEN...Until 10 AM PST Friday.
* IMPACTS...Travel could be affected.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Slow down and use caution while traveling.
The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.
&&
$$1 follow-up statement
451 WWUS45 KMSO 310305 WSWMSO URGENT - WINTER WEATHER MESSAGE National Weather Service Missoula MT 805 PM MST Thu Dec 30 2021 IDZ007-311800- /O.EXP.KMSO.WS.W.0015.000000T0000Z-211231T0300Z/ /O.CON.KMSO.WW.Y.0082.000000T0000Z-211231T1800Z/ Orofino/Grangeville Region- 705 PM PST Thu Dec 30 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM PST FRIDAY... ...WINTER STORM WARNING HAS EXPIRED... * WHAT...Snow. Additional snow accumulations of 2 to 4 inches. * WHERE...Camas Prairie, Grangeville and vicinity, and Greer Grade. * WHEN...For the Winter Weather Advisory, from 7 PM this evening to 10 AM PST Friday. * IMPACTS...Travel could be affected. 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. && $$ MTZ002-311800- /O.CON.KMSO.WW.Y.0081.000000T0000Z-211231T1800Z/ West Glacier Region- 805 PM MST Thu Dec 30 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST FRIDAY... * WHAT...Snow. Additional snow accumulations of 1 to 3 inches. * WHERE...Bad Rock Canyon, Essex, Highway 83 Bigfork to Swan Lake, Marias Pass, and Polebridge. * WHEN...Until 11 AM MST Friday. * IMPACTS...Travel could be affected. Patchy blowing snow could significantly reduce visibility. The dangerously cold wind chills as low as 30 below zero could cause frostbite on exposed skin in as little as 10 minutes. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions for the state you are calling from can be obtained by calling 5 1 1. && $$ MTZ004-311800- /O.CON.KMSO.WW.Y.0081.000000T0000Z-211231T1800Z/ Lower Clark Fork Region- 805 PM MST Thu Dec 30 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST FRIDAY... * WHAT...Snow. Additional snow accumulations of 1 to 3 inches. * WHERE...Evaro Hill, Highway 200 Thompson Falls to Plains, Highway 200 Trout Creek to Heron, and I-90 Lookout Pass to Haugan. * WHEN...Until 11 AM MST Friday. * IMPACTS...Travel could be affected. The cold wind chills as low as 10 below zero could result in hypothermia if precautions are not taken. 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. && $$ IDZ005-311800- /O.CON.KMSO.WW.Y.0081.000000T0000Z-211231T1800Z/ Northern Clearwater Mountains- 705 PM PST Thu Dec 30 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM PST FRIDAY... * WHAT...Snow. Additional snow accumulations of 2 to 4 inches. * WHERE...Elk River, Highway 11 Pierce to Headquarters, and Pierce. * WHEN...Until 10 AM PST Friday. * IMPACTS...Travel could be affected. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions for the state you are calling from can be obtained by calling 5 1 1. && $$ IDZ006-311800- /O.CON.KMSO.WW.Y.0081.000000T0000Z-211231T1800Z/ Southern Clearwater Mountains- 705 PM PST Thu Dec 30 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM PST FRIDAY... * WHAT...Snow. Additional snow accumulations of 2 to 4 inches. * WHERE...Dixie, Elk City, and Highway 12 Lowell to Lolo Pass. * WHEN...Until 10 AM PST Friday. * IMPACTS...Travel could be affected. The cold wind chills as low as 10 below zero could result in hypothermia if precautions are not taken. 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. && $$ IDZ008-311800- /O.CON.KMSO.WW.Y.0081.000000T0000Z-211231T1800Z/ Lower Hells Canyon/Salmon River Region- 705 PM PST Thu Dec 30 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 10 AM PST FRIDAY... * WHAT...Snow. Additional snow accumulations of 1 to 3 inches. * WHERE...Lower Hells Canyon/Salmon River Region. * WHEN...Until 10 AM PST Friday. * IMPACTS...Travel could be affected. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions for the state you are calling from can be obtained by calling 5 1 1. && $$
The office that day
Everything else NWS Missoula, MT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 30, 7:50 AM PST | Winter Weather Advisory | MSO | Clearwater, Idaho | 26 hr |
Nearby
Winter Storm Warnings in Idaho, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.