Alert archive / Montana / Winter Storm Warnings in 2021

Winter Storm Warning 14, NWS Missoula, MT

December 24, 2021Flathead County, Lake County, Montana

NWS Missoula, MT issued this winter storm warning at Dec 24, 2021, 12:32 PM MST for Flathead County, Lake County, Montana. It took effect at Dec 24, 2021, 5:00 PM MST. It was in force for 18 hr. 7 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 24, 2021, 12:32 PM MST (19:32 UTC)
In effect from
Dec 24, 2021, 5:00 PM MST
Expired
Dec 25, 2021, 11:00 AM MST
In force
18 hr
Issued by
NWS Missoula, MT

Counties Flathead County, MT, Lake County, MT

The radar

The Missoula radar (KMSX), 104 km from the middle of the area, began a volume at 19:36 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 25, 12:28 AM MSTHEAVY SNOW 45 Nw Coram, MT
Dec 25, 9:51 AM MSTSNOW 0.58 N Finley Point, MTSNOW OCCURRENCE WITHIN AN HOUR OF DAILY MORNING REPORT.
Dec 25, 10:00 AM MSTSNOW 4.94 Se Essex, MTMESONET STATION S11MT SHED 11.
Dec 25, 10:00 AM MSTSNOW 6.22 Sw Blacktail - Railro, MTMESONET STATION SH7MT SHED 7.
Dec 25, 10:00 AM MSTSNOW 76 N Whitefish, MTMESONET STATION BIGMS 6.3 N WHITEFISH (GNP).
Dec 25, 10:00 AM MSTSNOW 7.95 Ene Blacktail - Railr, MTMESONET STATION MRPMT MARIAS PASS.
Dec 25, 10:00 AM MSTSNOW 10.93 Sw Pinnacle, MTMESONET STATION TRSMT TUNNEL RIDGE SNOW.

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 12:00Z, 7.5 hours before the alert went out and 177 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, Spokane, WA at 12:00Z on 2021-12-24Temperature 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 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Spokane, WA at 12:00Z on 2021-12-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 91 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
815 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
91 m²/s²
0-3 km storm-relative helicity
79 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

589 
WWUS45 KMSO 241932
WSWMSO

URGENT - WINTER WEATHER MESSAGE
National Weather Service Missoula MT
1232 PM MST Fri Dec 24 2021

MTZ002-251800-
/O.UPG.KMSO.WS.A.0010.211225T0000Z-211225T1800Z/
/O.NEW.KMSO.WS.W.0014.211225T0000Z-211225T1800Z/
/O.CON.KMSO.WW.Y.0076.000000T0000Z-211225T0000Z/
West Glacier Region-
1232 PM MST Fri Dec 24 2021

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

* WHAT...For the Winter Storm Warning, heavy snow expected. Total
  snow accumulations of 5 to 8 inches along Hwy 2 to about West
  Glacier, then 8 to 12 inches from West Glacier to Marias Pass. 
  For the Winter Weather Advisory, snow. Additional snow 
  accumulations of up to one inch.

* WHERE...Bad Rock Canyon, Essex, Highway 83 Bigfork to Swan 
  Lake, Marias Pass, and Polebridge.

* WHEN...For the Winter Storm Warning, from 5 PM this afternoon 
  to 11 AM MST Saturday. For the Winter Weather Advisory, until 
  5 PM MST this afternoon.

* IMPACTS...Travel could be affected. The cold wind chills as 
  low as 20 below zero could result in hypothermia if 
  precautions are not taken.

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.

&&

$$

MTZ001-251945-
/O.NEW.KMSO.WS.A.0011.211226T0900Z-211227T0600Z/
/O.CON.KMSO.WW.Y.0077.211224T2100Z-211225T1800Z/
Kootenai/Cabinet Region-
1232 PM MST Fri Dec 24 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST
SATURDAY...
...WINTER STORM WATCH IN EFFECT FROM LATE SATURDAY NIGHT THROUGH
SUNDAY EVENING...

* WHAT...For the Winter Weather Advisory, snow expected. Total
  snow accumulations of 3 to 9 inches. For the Winter Storm Watch, snow
  possible, along with blowing snow and a sudden drop in 
  temperature to below 0 degrees. Total snow accumulations of 2 to
  4 inches possible.
 
* WHERE...Highway 2 Kalispell to Libby, Highway 37 Eureka to 
  Libby, Highway 56 Bull Lake Road, and Highway 93 Eureka to 
  Whitefish.

* WHEN...For the Winter Weather Advisory, until 11 AM MST 
  Saturday. For the Winter Storm Watch, from late Saturday night 
  through Sunday evening.

* IMPACTS...Travel could be very difficult to impossible. The 
  cold wind chills as low as 30 below zero could cause frostbite 
  on exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

Monitor the latest forecasts for updates on this situation. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

MTZ004-251800-
/O.CON.KMSO.WW.Y.0076.000000T0000Z-211225T1800Z/
Lower Clark Fork Region-
1232 PM MST Fri Dec 24 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST
SATURDAY...

* WHAT...Snow. Additional snow accumulations of 4 to 8 inches 
  over Lookout Pass, with 2 to 4 inches across valley locations 
  near the Idaho border. Up to 2 inches elsewhere.

* WHERE...Highway 200 Thompson Falls to Plains, Highway 200 
  Trout Creek to Heron, and I-90 Lookout Pass to Haugan.

* WHEN...Until 11 AM MST Saturday.

* 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.

&&

$$

MTZ003-251945-
/O.NEW.KMSO.WS.A.0011.211226T0900Z-211227T0600Z/
Flathead/Mission Valleys-
1232 PM MST Fri Dec 24 2021

...WINTER STORM WATCH IN EFFECT FROM LATE SATURDAY NIGHT THROUGH
SUNDAY EVENING...

* WHAT...Snow. Total snow accumulations of up to two inches
  possible, along with blowing snow and a sudden drop in 
  temperature to single digits.

* WHERE...Flathead Lake, Flathead Valley, Mission Valley, and 
  Polson.

* WHEN...From late Saturday night through Sunday evening.

* IMPACTS...Travel could be affected. The cold wind chills as 
  low as 15 below zero could result in hypothermia if 
  precautions are not taken.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

MTZ007-251945-
/O.NEW.KMSO.WS.A.0011.211226T0900Z-211227T0600Z/
Butte/Blackfoot Region-
1232 PM MST Fri Dec 24 2021

...WINTER STORM WATCH IN EFFECT FROM LATE SATURDAY NIGHT THROUGH
SUNDAY EVENING...

* WHAT...Heavy snow possible. Total snow accumulations of up to 
  two inches possible.

* WHERE...Butte, Georgetown Lake, Highway 12 Garrison to 
  Elliston, Homestake Pass, and MacDonald Pass.

* WHEN...From late Saturday night through Sunday evening.

* IMPACTS...Travel could be affected. The cold wind chills as 
  low as 25 below zero could cause frostbite on exposed skin in 
  as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$
3 follow-up statements
602 
WWUS45 KMSO 241937
WSWMSO

URGENT - WINTER WEATHER MESSAGE
National Weather Service Missoula MT
1237 PM MST Fri Dec 24 2021

MTZ002-251800-
/O.CON.KMSO.WS.W.0014.211225T0000Z-211225T1800Z/
/O.CON.KMSO.WW.Y.0076.000000T0000Z-211225T0000Z/
West Glacier Region-
1237 PM MST Fri Dec 24 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...
...WINTER STORM WARNING REMAINS IN EFFECT FROM 5 PM THIS
AFTERNOON TO 11 AM MST SATURDAY...

* WHAT...For the Winter Storm Warning, heavy snow expected. 
  Total snow accumulations of 5 to 8 inches along Hwy 2 to about 
  West Glacier, then 8 to 12 inches from West Glacier to Marias 
  Pass. For the Winter Weather Advisory, snow. Additional snow 
  accumulations of up to one inch.

* WHERE...Bad Rock Canyon, Essex, Highway 83 Bigfork to Swan 
  Lake, Marias Pass, and Polebridge.

* WHEN...For the Winter Storm Warning, from 5 PM this afternoon 
  to 11 AM MST Saturday. For the Winter Weather Advisory, until 
  5 PM MST this afternoon.

* IMPACTS...Travel could be affected. The cold wind chills as 
  low as 20 below zero could result in hypothermia if 
  precautions are not taken.

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.

&&

$$

MTZ001-251945-
/O.CON.KMSO.WW.Y.0077.211224T2100Z-211225T1800Z/
/O.CON.KMSO.WS.A.0011.211226T0900Z-211227T0600Z/
Kootenai/Cabinet Region-
1237 PM MST Fri Dec 24 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST
SATURDAY...
...WINTER STORM WATCH REMAINS IN EFFECT FROM LATE SATURDAY NIGHT
THROUGH SUNDAY EVENING...

* WHAT...For the Winter Weather Advisory, snow expected. Total 
  snow accumulations of 3 to 9 inches. For the Winter Storm 
  Watch, snow possible, along with blowing snow and a sudden 
  drop in temperature to below 0 degrees. Total snow 
  accumulations of 2 to 4 inches possible.

* WHERE...Highway 2 Kalispell to Libby, Highway 37 Eureka to 
  Libby, Highway 56 Bull Lake Road, and Highway 93 Eureka to 
  Whitefish.

* WHEN...For the Winter Weather Advisory, until 11 AM MST 
  Saturday. For the Winter Storm Watch, from late Saturday night 
  through Sunday evening.

* IMPACTS...Travel could be very difficult to impossible. The 
  cold wind chills as low as 30 below zero could cause frostbite 
  on exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

Monitor the latest forecasts for updates on this situation.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

MTZ004-251800-
/O.CON.KMSO.WW.Y.0076.000000T0000Z-211225T1800Z/
Lower Clark Fork Region-
1237 PM MST Fri Dec 24 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST
SATURDAY...

* WHAT...Snow. Additional snow accumulations of 4 to 8 inches 
  over Lookout Pass, with 2 to 4 inches across valley locations 
  near the Idaho border. Up to 2 inches elsewhere.

* WHERE...Highway 200 Thompson Falls to Plains, Highway 200 
  Trout Creek to Heron, and I-90 Lookout Pass to Haugan.

* WHEN...Until 11 AM MST Saturday.

* 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.

&&

$$

MTZ003-251945-
/O.CON.KMSO.WS.A.0011.211226T0900Z-211227T0600Z/
Flathead/Mission Valleys-
1237 PM MST Fri Dec 24 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM LATE SATURDAY NIGHT
THROUGH SUNDAY EVENING...

* WHAT...Snow. Total snow accumulations of 1 to 4 inches 
  possible, along with blowing snow and a sudden drop in 
  temperature to single digits.

* WHERE...Flathead Lake, Flathead Valley, Mission Valley, and 
  Polson.

* WHEN...From late Saturday night through Sunday evening.

* IMPACTS...Travel could be affected. The cold wind chills as 
  low as 15 below zero could result in hypothermia if 
  precautions are not taken.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation.

&&

$$

MTZ007-251945-
/O.CON.KMSO.WS.A.0011.211226T0900Z-211227T0600Z/
Butte/Blackfoot Region-
1237 PM MST Fri Dec 24 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM LATE SATURDAY NIGHT
THROUGH SUNDAY EVENING...

* WHAT...Snow. Total snow accumulations of 1 to 4 inches possible,
  along with blowing snow and a sudden drop in temperature below 0
  degrees

* WHERE...Butte, Georgetown Lake, Highway 12 Garrison to 
  Elliston, Ovando, Homestake Pass, and MacDonald Pass.

* WHEN...From late Saturday night through Sunday evening.

* IMPACTS...Travel could be affected. The cold wind chills as 
  low as 25 below zero could cause frostbite on exposed skin in 
  as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation.

&&

$$
111 
WWUS45 KMSO 250951
WSWMSO

URGENT - WINTER WEATHER MESSAGE
National Weather Service Missoula MT
251 AM MST Sat Dec 25 2021

MTZ002-251800-
/O.CON.KMSO.WS.W.0014.000000T0000Z-211225T1800Z/
West Glacier Region-
251 AM MST Sat Dec 25 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...

* WHAT...Heavy snow. Additional snow accumulations of 3 to 6 
  inches.

* WHERE...Bad Rock Canyon, Essex, Highway 83 Bigfork to Swan 
  Lake, Marias Pass, and Polebridge.

* WHEN...Until 11 AM MST this morning.

* IMPACTS...Travel could be very difficult. Areas of blowing and
  drifting snow are expected from Essex to Marias Pass. The cold 
  wind chills as low as 20 below zero could result in hypothermia 
  if precautions are not taken. 

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.

&&

$$

MTZ001-261000-
/O.EXT.KMSO.WS.A.0011.211226T1200Z-211227T0600Z/
/O.CON.KMSO.WW.Y.0077.000000T0000Z-211225T1800Z/
Kootenai/Cabinet Region-
251 AM MST Sat Dec 25 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...
...WINTER STORM WATCH NOW IN EFFECT FROM LATE TONIGHT THROUGH
SUNDAY EVENING...

* WHAT...For the Winter Weather Advisory, snow. Additional snow
  accumulations of 1 to 3 inches. For the Winter Storm Watch,
  heavy snow possible, along with blowing snow, and a sudden drop
  in temperature to below 0 degrees. Total snow accumulations of 
  2 to 4 inches possible.

* WHERE...Highway 2 Kalispell to Libby, Highway 37 Eureka to 
  Libby, Highway 56 Bull Lake Road, and Highway 93 Eureka to 
  Whitefish.

* WHEN...For the Winter Weather Advisory, until 11 AM MST this 
  morning. For the Winter Storm Watch, from late tonight through 
  Sunday evening.

* IMPACTS...Travel could be very difficult to impossible. The 
  cold wind chills as low as 30 below zero could cause frostbite 
  on exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

Monitor the latest forecasts for updates on this situation. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

MTZ004-251800-
/O.CON.KMSO.WW.Y.0076.000000T0000Z-211225T1800Z/
Lower Clark Fork Region-
251 AM MST Sat Dec 25 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...

* WHAT...Snow. Additional snow accumulations of 2 to 5 inches from
  Haugan to Lookout Pass, with up to one inch across valley
  locations. 

* 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 this morning.

* 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.

&&

$$

MTZ003-261000-
/O.EXT.KMSO.WS.A.0011.211226T1200Z-211227T0600Z/
Flathead/Mission Valleys-
251 AM MST Sat Dec 25 2021

...WINTER STORM WATCH NOW IN EFFECT FROM LATE TONIGHT THROUGH
SUNDAY EVENING...

* WHAT...Heavy snow possible. Total snow accumulations of 1 to 4
  inches possible, along with blowing snow, and a sudden drop in
  temperature to single digits.

* WHERE...Flathead Lake, Flathead Valley, Mission Valley, and 
  Polson.

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

* IMPACTS...Travel could be affected. The cold wind chills as 
  low as 15 below zero could result in hypothermia if 
  precautions are not taken.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

MTZ007-261000-
/O.EXT.KMSO.WS.A.0011.211226T1200Z-211227T0600Z/
Butte/Blackfoot Region-
251 AM MST Sat Dec 25 2021

...WINTER STORM WATCH NOW IN EFFECT FROM LATE TONIGHT THROUGH
SUNDAY EVENING...

* WHAT...Heavy snow possible. Total snow accumulations of 1 to 4
  inches possible, along with blowing snow, and a sudden drop in
  temperature below 0 degrees

* WHERE...Butte, Georgetown Lake, Highway 12 Garrison to 
  Elliston, Homestake Pass, and MacDonald Pass.

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

* IMPACTS...Travel could be affected. The cold wind chills as 
  low as 25 below zero could cause frostbite on exposed skin in 
  as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$
678 
WWUS45 KMSO 251800
WSWMSO

URGENT - WINTER WEATHER MESSAGE
National Weather Service Missoula MT
1100 AM MST Sat Dec 25 2021

MTZ002-261800-
/O.EXP.KMSO.WS.W.0014.000000T0000Z-211225T1800Z/
/O.NEW.KMSO.WW.Y.0078.211225T1800Z-211226T0000Z/
/O.NEW.KMSO.WC.Y.0004.211226T0000Z-211226T1800Z/
West Glacier Region-
1100 AM MST Sat Dec 25 2021

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...
...WIND CHILL ADVISORY IN EFFECT FROM 5 PM THIS AFTERNOON TO
11 AM MST SUNDAY...
...WINTER STORM WARNING HAS EXPIRED...

* WHAT...For the Winter Weather Advisory, snow. Additional snow
  accumulations of 1 to 3 inches. For the Wind Chill Advisory,
  very cold wind chills expected. Wind chills as low as 30 below 
  zero.

* WHERE...Bad Rock Canyon, Essex, Highway 83 Bigfork to Swan 
  Lake, Marias Pass, and Polebridge.

* WHEN...For the Winter Weather Advisory, until 5 PM MST this 
  afternoon. For the Wind Chill Advisory, from 5 PM this 
  afternoon to 11 AM MST Sunday.

* IMPACTS...Travel could be affected. The dangerously cold wind 
  chills could cause frostbite on exposed skin in as little as 
  10 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

Use caution while traveling outside. Wear appropriate clothing, a
hat, and gloves. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

MTZ001-261800-
/O.EXP.KMSO.WW.Y.0077.000000T0000Z-211225T1800Z/
/O.CON.KMSO.WS.A.0011.211226T1200Z-211227T0600Z/
Kootenai/Cabinet Region-
1100 AM MST Sat Dec 25 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM LATE TONIGHT THROUGH
SUNDAY EVENING...
...WINTER WEATHER ADVISORY HAS EXPIRED...

* WHAT...Heavy snow possible. Total snow accumulations of 2 to 4 
  inches possible.

* WHERE...Highway 2 Kalispell to Libby, Highway 37 Eureka to 
  Libby, Highway 56 Bull Lake Road, and Highway 93 Eureka to 
  Whitefish.

* WHEN...For the Winter Weather Advisory, until 11 AM MST this 
  morning. For the Winter Storm Watch, from late tonight through 
  Sunday evening.

* IMPACTS...Travel could be very difficult. The cold wind chills 
  as low as 30 below zero could cause frostbite on exposed skin 
  in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

MTZ004-251900-
/O.EXP.KMSO.WW.Y.0076.000000T0000Z-211225T1800Z/
Lower Clark Fork Region-
1100 AM MST Sat Dec 25 2021

...WINTER WEATHER ADVISORY HAS EXPIRED...

$$

MTZ003-261800-
/O.CON.KMSO.WS.A.0011.211226T1200Z-211227T0600Z/
Flathead/Mission Valleys-
1100 AM MST Sat Dec 25 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM LATE TONIGHT THROUGH
SUNDAY EVENING...

* WHAT...Heavy snow possible. Total snow accumulations of 1 to 4 
  inches possible, along with blowing snow, and a sudden drop in 
  temperature to single digits.

* WHERE...Flathead Lake, Flathead Valley, Mission Valley, and 
  Polson.

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

* IMPACTS...Travel could be affected. The cold wind chills as 
  low as 15 below zero could result in hypothermia if 
  precautions are not taken.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation.

&&

$$

MTZ007-261800-
/O.CON.KMSO.WS.A.0011.211226T1200Z-211227T0600Z/
Butte/Blackfoot Region-
1100 AM MST Sat Dec 25 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM LATE TONIGHT THROUGH
SUNDAY EVENING...

* WHAT...Heavy snow possible. Total snow accumulations of 1 to 4 
  inches possible, along with blowing snow, and a sudden drop in 
  temperature below 0 degrees.

* WHERE...Butte, Georgetown Lake, Highway 12 Garrison to 
  Elliston, Homestake Pass, and MacDonald Pass.

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

* IMPACTS...Travel could be affected. The cold wind chills as 
  low as 25 below zero could cause frostbite on exposed skin in 
  as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation.

&&

$$

The office that day

Everything else NWS Missoula, MT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 24, 2:52 AM MSTWinter Storm WatchMSOFlathead, Lake10 hr
Dec 24, 2:52 AM MSTWinter Weather AdvisoryMSOFlathead, Lincoln, Sanders32 hr
Dec 24, 12:32 PM MSTWinter Storm WatchMSODeer Lodge, Flathead, Granite, Lake, Lincoln, Powell and 2 more24 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.