Alert archive / Montana / Winter Storm Warnings in 2021
Winter Storm Warning 1, NWS Missoula, MT
NWS Missoula, MT issued this winter storm warning at Jan 2, 2021, 3:16 AM MST for Mineral County, Missoula County, Sanders County, Montana. It took effect at Jan 2, 2021, 5:00 PM MST. It was in force for 19 hr. 1 report 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
- Jan 2, 2021, 3:16 AM MST (10:16 UTC)
- In effect from
- Jan 2, 2021, 5:00 PM MST
- Expired
- Jan 3, 2021, 12:22 PM MST
- In force
- 19 hr
- Issued by
- NWS Missoula, MT
Counties Mineral County, MT, Missoula County, MT, Sanders County, MT
The radar
The Missoula radar (KMSX), 59 km from the middle of the area, began a volume at 10:15 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Jan 3, 10:35 AM MST | HEAVY SNOW 9 | 3 Nnw East Portal, MT | MDT REPORTED SEVERE DRIVING CONDITIONS DUE TO HEAVY SNOW FROM LOOKOUT PASS TO TAFT 7:35 AM TO 10:30 AM WITH 9 INCHES REPORTED AT THE BASE OF SKI LOOKOUT. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Spokane, WA (KOTX), launched 00:00Z, 10.3 hours before the alert went out and 137 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
- 1191 m above ground
- 0-6 km bulk shear
- 45 kt
- 0-1 km storm-relative helicity
- 155 m²/s²
- 0-3 km storm-relative helicity
- 219 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
560 WWUS45 KMSO 021016 WSWMSO URGENT - WINTER WEATHER MESSAGE National Weather Service Missoula MT 316 AM MST Sat Jan 2 2021 MTZ004-032000- /O.UPG.KMSO.WS.A.0001.210103T0000Z-210103T2100Z/ /O.NEW.KMSO.WS.W.0001.210103T0000Z-210103T2000Z/ Lower Clark Fork Region- 316 AM MST Sat Jan 2 2021 ...WINTER STORM WARNING IN EFFECT FROM 5 PM THIS AFTERNOON TO 1 PM MST SUNDAY... * WHAT...Heavy mixed precipitation expected. A burst of snow will impact Lookout Pass through daybreak today, accumulating 3 to 6 inches. The next period of interest will be tonight into Sunday with heavy mixed precipitation expected. Additional snow accumulations of up 12 inches at Lookout Pass with only light amounts for lower elevations. Ice accumulations of a light glaze are possible for valleys as well. Highest impacts are expected from Taft to Lookout Pass on I-90, however icy and slick conditions may exist east of Taft. Winds gusting as high as 45 mph. * WHERE...Evaro Hill, Highway 200 Thompson Falls to Plains, Highway 200 Trout Creek to Heron, and I-90 Lookout Pass to Haugan. * WHEN...From 5 PM this afternoon to 1 PM MST Sunday. * IMPACTS...Travel will be difficult from Taft to Lookout Pass. Patchy blowing snow could significantly reduce visibility. Gusty winds could bring down tree branches leading to localized power outages. 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. && $$
2 follow-up statements
926 WWUS45 KMSO 022058 WSWMSO URGENT - WINTER WEATHER MESSAGE National Weather Service Missoula MT 158 PM MST Sat Jan 2 2021 MTZ004-032000- /O.CON.KMSO.WS.W.0001.210103T0000Z-210103T2000Z/ Lower Clark Fork Region- 158 PM MST Sat Jan 2 2021 ...WINTER STORM WARNING REMAINS IN EFFECT FROM 5 PM THIS AFTERNOON TO 1 PM MST SUNDAY... * WHAT...Heavy mixed precipitation expected. Accumulations of up 12 inches at Lookout Pass with only light amounts for lower elevations. Ice accumulations of a light glaze are possible for valleys as well. Highest impacts are expected from Taft to Lookout Pass on I-90, however icy and slick conditions may exist east of Taft. Winds gusting as high as 45 mph in the higher elevations. * WHERE...Evaro Hill, Highway 200 Thompson Falls to Plains, Highway 200 Trout Creek to Heron, and I-90 Lookout Pass to Haugan. * WHEN...From 5 PM this afternoon to 1 PM MST Sunday. * IMPACTS...Travel could be affected. Patchy blowing snow could significantly reduce visibility. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions for the state you are calling from can be obtained by calling 5 1 1. && $$ MTZ006-032000- /O.NEW.KMSO.WW.Y.0001.210103T0000Z-210103T2000Z/ Bitterroot/Sapphire Mountains- 158 PM MST Sat Jan 2 2021 ...WINTER WEATHER ADVISORY IN EFFECT FROM 5 PM THIS AFTERNOON TO 1 PM MST SUNDAY... * WHAT...Snow expected. Total snow accumulations of 3 to 6 inches. Winds gusting as high as 50 mph. * WHERE...Bitterroot/Sapphire Mountains. * WHEN...From 5 PM this afternoon to 1 PM MST Sunday. * IMPACTS...Travel could be affected. Patchy blowing snow could significantly reduce visibility. Gusty winds could bring down tree branches. 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. && $$ MTZ002-032000- /O.NEW.KMSO.WW.Y.0001.210103T0600Z-210103T2000Z/ West Glacier Region- 158 PM MST Sat Jan 2 2021 ...WINTER WEATHER ADVISORY IN EFFECT FROM 11 PM THIS EVENING TO 1 PM MST SUNDAY... * WHAT...Mixed precipitation expected. Total snow accumulations of trace to 2 inches below 3500 feet and 4 to 9 inches Essex to Marias Pass and ice accumulations of a light glaze. Winds gusting as high as 55 mph in the higher elevations. * WHERE...Bad Rock Canyon, Essex, Highway 83 Bigfork to Swan Lake, Marias Pass, and Polebridge. * WHEN...From 11 PM this evening to 1 PM MST Sunday. * IMPACTS...Travel could be affected. Areas of blowing snow could significantly reduce visibility. Strong winds could cause damage to trees and power lines. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions for the state you are calling from can be obtained by calling 5 1 1. && $$ IDZ005-006-032000- /O.NEW.KMSO.WW.Y.0001.210103T0000Z-210103T2000Z/ Northern Clearwater Mountains-Southern Clearwater Mountains- 1258 PM PST Sat Jan 2 2021 ...WINTER WEATHER ADVISORY IN EFFECT FROM 4 PM THIS AFTERNOON TO NOON PST SUNDAY ABOVE 3500 FEET... * WHAT...Mixed precipitation expected above 3500 feet. Total snow accumulations of 4 to 7 inches and ice accumulations of a light glaze. Winds gusting as high as 40 mph in the higher elevations. * WHERE...Lolo Pass...Northern Clearwater Mountains and Southern Clearwater Mountains. * WHEN...From 4 PM this afternoon to noon PST Sunday. * IMPACTS...Travel could be affected. Patchy 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. && $$
153 WWUS45 KMSO 031922 WSWMSO URGENT - WINTER WEATHER MESSAGE National Weather Service Missoula MT 1222 PM MST Sun Jan 3 2021 MTZ004-032030- /O.CAN.KMSO.WS.W.0001.000000T0000Z-210103T2000Z/ Lower Clark Fork Region- 1222 PM MST Sun Jan 3 2021 ...WINTER STORM WARNING IS CANCELLED... Conditions have significantly improved. $$ MTZ006-032030- /O.CON.KMSO.WW.Y.0001.000000T0000Z-210103T2000Z/ Bitterroot/Sapphire Mountains- 1222 PM MST Sun Jan 3 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 1 PM MST THIS AFTERNOON... * WHAT...Snow. Additional snow accumulations of up to one inch. Winds gusting as high as 40 mph. * WHERE...Lost Trail Pass...Bitterroot/Sapphire Mountains. * WHEN...Until 1 PM MST this afternoon. * IMPACTS...Travel could be affected. 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. && $$ MTZ002-032030- /O.CON.KMSO.WW.Y.0001.000000T0000Z-210103T2000Z/ West Glacier Region- 1222 PM MST Sun Jan 3 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 1 PM MST THIS AFTERNOON... * WHAT...Snow. Additional snow accumulations of up to one inch. Winds gusting as high as 50 mph. * WHERE...Bad Rock Canyon, Essex, Highway 83 Bigfork to Swan Lake, Marias Pass, and Polebridge. * WHEN...Until 1 PM MST this afternoon. * IMPACTS...Travel could be affected. Widespread blowing snow could significantly reduce visibility. Gusty winds could bring down tree branches. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions for the state you are calling from can be obtained by calling 5 1 1. && $$ IDZ005-006-032030- /O.CON.KMSO.WW.Y.0001.000000T0000Z-210103T2000Z/ Northern Clearwater Mountains-Southern Clearwater Mountains- 1122 AM PST Sun Jan 3 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL NOON PST TODAY ABOVE 3500 FEET... * WHAT...Snow above 3500 feet. Additional snow accumulations of up to one inch. Winds gusting as high as 35 mph. * WHERE...Southern Clearwater Mountains and Northern Clearwater Mountains. * WHEN...Until noon PST today. * IMPACTS...Travel could be affected. Patchy 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. && $$
The office that day
Everything else NWS Missoula, MT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jan 2, 1:37 PM MST | Wind Advisory | MSO | Deer Lodge, Flathead, Granite, Lake, Lincoln, Missoula and 4 more | 27 hr |
| Jan 2, 1:58 PM MST | Winter Weather Advisory | MSO | Flathead, Granite, Lake, Missoula, Ravalli | 23 hr |
Nearby
Winter Storm Warnings in Montana, 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.