Alert archive / Montana / Winter Storm Warnings in 2019

Winter Storm Warning 10, NWS Missoula, MT

March 1, 201910 counties in Montana

NWS Missoula, MT issued this winter storm warning at Mar 1, 2019, 3:33 AM MST for 10 counties in Montana. It took effect at Mar 1, 2019, 6:00 AM MST. It was in force for 28 hr. 23 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
Mar 1, 2019, 3:33 AM MST (10:33 UTC)
In effect from
Mar 1, 2019, 6:00 AM MST
Expired
Mar 2, 2019, 9:44 AM MST
In force
28 hr
Issued by
NWS Missoula, MT

Counties Deer Lodge County, MT, Flathead County, MT, Granite County, MT, Lake County, MT, Mineral County, MT, Missoula County, MT, Powell County, MT, Ravalli County, MT, Sanders County, MT, Silver Bow County, MT

The radar

The Missoula radar (KMSX), 18 km from the middle of the area, began a volume at 10:39 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
Mar 1, 7:00 AM MSTSNOW 21 Se Marion, MTCOCORAHS STATION MT-FH-12, 1 ESE MARION.
Mar 1, 7:00 AM MSTSNOW 22 Nw Kalispell, MTCOCORAHS STATION MT-FH-13, 1 NW KALISPELL.
Mar 1, 7:00 AM MSTSNOW 2.2Whitefish, MTCOCORAHS STATION MT-FH-4, WHITEFISH.
Mar 1, 7:00 AM MSTSNOW 2.53 Ene Bigfork, MTCOCORAHS STATION MT-FH-16, 2 E BIGFORK.
Mar 1, 7:00 AM MSTSNOW 2.83 Wnw West Valley, MTCOCORAHS STATION MT-DL-1, 7 NW ANACONDA.
Mar 1, 7:15 AM MSTSNOW 25 N Creston, MTCOCORAHS STATION MT-FH-17, 5 NNW CRESTON.
Mar 1, 1:27 PM MSTSNOW 8Olney, MTTOTAL SINCE LAST NIGHT.
Mar 1, 5:19 PM MSTSNOW 4Columbia Falls, MT
Mar 1, 7:30 PM MSTHEAVY SNOW 5Lolo, MTFELL IN 3 HOURS FROM A HEAVY SNOW BAND.
Mar 1, 9:43 PM MSTSNOW 2.6Bigfork, MTBad visibility and drifting
Mar 1, 10:00 PM MSTSNOW 24 Ssw Missoula, MTLIGHT TO MODERATE SNOW STARTING AROUND 4PM, ACCUMULATED UP TO 2 INCHES BY 10PM 3/1. SOON AFTER, GUSTY EAST WINDS ARRIVED AND STARTED TO SEE BLOWING AND DRIFTING SNOW REDUCING VISIBILITY.
Mar 2, 5:56 AM MSTSNOW 34 N Georgetown, MTDISCOVERY SKI RESORT 24 HOUR SNOWFALL TOTAL.
Mar 2, 6:21 AM MSTSNOW 2.43 Ese Bigfork, MTCOCORAHS STATION MT-LK-15, 3 E BIGFORK.
Mar 2, 6:30 AM MSTSNOW 25 N Creston, MTCOCORAHS STATION MT-FH-17, 5 NNW CRESTON.
Mar 2, 6:39 AM MSTSNOW 3Polson, MTROAD REPORTS STATED BLOWING AND DRIFTING SNOW AROUND FLATHEAD LAKE OVERNIGHT.
Mar 2, 6:51 AM MSTSNOW 34 Ese Evaro, MTSNOW BOWL SKI RESORT NEW SNOW IN THE LAST 24 HOURS.
Mar 2, 7:00 AM MSTSNOW 2.3Turah, MTCOCORAHS STATION MT-MS-23, TURAH.
Mar 2, 7:00 AM MSTSNOW 2.63 Se Condon, MTCOCORAHS STATION MT-MS-27, 3 SE CONDON.
Mar 2, 7:00 AM MSTSNOW 3.6Whitefish, MTCOCORAHS STATION MT-FH-4, WHITEFISH.
Mar 2, 8:00 AM MSTSNOW 2.31 Wsw Rollins, MTCOCORAHS STATION MT-LK-11, ROLLINS.
Mar 2, 9:00 AM MSTSNOW 3.8Ronan, MTCOCORAHS STATION MT-LK-13, RONAN.
Mar 2, 9:19 AM MSTSNOW 4.58 N Finley Point, MTSNOW ACCUMULATED YESTERDAY AFTERNOON THROUGH THE OVERNIGHT HOURS.
Mar 2, 9:32 AM MSTSNOW 3Anaconda, MTSNOW FELL OVERNIGHT.

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, 10.6 hours before the alert went out and 212 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 00:00Z on 2019-03-01Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Spokane, WA at 00:00Z on 2019-03-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 43 square meters per square second.193958Sfc1 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
664 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
43 m²/s²
0-3 km storm-relative helicity
97 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

138 
WWUS45 KMSO 011033
WSWMSO

URGENT - WINTER WEATHER MESSAGE
National Weather Service Missoula MT
333 AM MST Fri Mar 1 2019

MTZ002-021045-
/O.UPG.KMSO.WS.A.0006.190301T1300Z-190302T1900Z/
/O.NEW.KMSO.WS.W.0010.190301T1300Z-190302T1900Z/
West Glacier Region-
333 AM MST Fri Mar 1 2019

...WINTER STORM WARNING IN EFFECT FROM 6 AM THIS MORNING TO NOON
MST SATURDAY...

* WHAT...Blowing and drifting snow followed by extremely cold wind
  chills expected. Total snow accumulations of 4 to 6 inches 
  expected.

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

* WHEN...From 6 AM this morning to noon MST Saturday.

* ADDITIONAL DETAILS...Travel could be very difficult. Areas of 
  blowing snow could significantly reduce visibility. The 
  dangerously cold wind chills as low as 40 below zero could 
  cause frostbite on exposed skin in as little as 10 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow means severe winter weather
conditions will make travel very hazardous or impossible. 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.

&&

$$

MTZ003-021045-
/O.UPG.KMSO.WS.A.0006.190301T1900Z-190302T1900Z/
/O.NEW.KMSO.WS.W.0010.190301T1700Z-190302T1900Z/
Flathead/Mission Valleys-
333 AM MST Fri Mar 1 2019

...WINTER STORM WARNING IN EFFECT FROM 10 AM THIS MORNING TO NOON
MST SATURDAY...

* WHAT...Blowing and drifting snow followed by extremely cold wind
  chills expected. Total snow accumulations of 1 to 3 inches 
  expected.

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

* WHEN...From 10 AM this morning to noon MST Saturday.

* ADDITIONAL DETAILS...Plan on slippery road conditions. Areas 
  of blowing snow could significantly reduce visibility. The 
  cold wind chills as low as 20 below zero could cause frostbite 
  on exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow means severe winter weather
conditions will make travel very hazardous or impossible. 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.

&&

$$

MTZ007-043-021045-
/O.UPG.KMSO.WS.A.0006.190301T1900Z-190302T1900Z/
/O.NEW.KMSO.WS.W.0010.190301T1700Z-190302T1900Z/
Butte/Blackfoot Region-Potomac/Seeley Lake Region-
333 AM MST Fri Mar 1 2019

...WINTER STORM WARNING IN EFFECT FROM 10 AM THIS MORNING TO NOON
MST SATURDAY...

* WHAT...Blowing and drifting snow followed by extremely cold wind
  chills. Total snow accumulations of 1 to 3 inches expected.

* WHERE...Georgetown Lake, Highway 12 Garrison to Elliston,
  Homestake Pass, MacDonald Pass, Highway 200 Bonner to Greenough, 
  and I-90 East Missoula to Bearmouth.

* WHEN...From 10 AM this morning to noon MST Saturday.

* ADDITIONAL DETAILS...Plan on slippery road conditions. 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...

A Winter Storm Warning for snow means severe winter weather
conditions will make travel very hazardous or impossible. 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.

&&

$$

MTZ006-021045-
/O.CON.KMSO.WS.A.0006.190301T1900Z-190302T1900Z/
Bitterroot/Sapphire Mountains-
333 AM MST Fri Mar 1 2019

...WINTER STORM WATCH REMAINS IN EFFECT FROM NOON MST TODAY
THROUGH SATURDAY MORNING...

* WHAT...Blowing and drifting snow possible followed by low wind
  chills. Total snow accumulations of up to two inches possible.

* WHERE...Bitterroot/Sapphire Mountains.

* WHEN...From noon MST today through Saturday morning.

* ADDITIONAL DETAILS...Plan on slippery road conditions. The 
  cold wind chills as low as 15 below zero could result in 
  hypothermia if precautions are not taken.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Watch means there is potential for significant
snow, sleet or ice accumulations that may impact travel. Continue
to monitor the latest forecasts. 

&&

$$

MTZ005-021045-
/O.CON.KMSO.WS.A.0006.190302T0100Z-190302T1900Z/
Missoula/Bitterroot Valleys-
333 AM MST Fri Mar 1 2019

...WINTER STORM WATCH REMAINS IN EFFECT FROM THIS EVENING THROUGH
SATURDAY MORNING...

* WHAT...Blowing and drifting snow possible followed by low wind
  chills. Total new snow accumulations of up to one inch 
  possible.

* WHERE...Missoula Valley.

* WHEN...From this evening through Saturday morning.

* ADDITIONAL DETAILS...Plan on slippery road conditions. The 
  cold wind chills as low as 15 below zero could result in 
  hypothermia if precautions are not taken.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Watch means there is potential for significant
snow, sleet or ice accumulations that may impact travel. Continue
to monitor the latest forecasts. 

&&

$$

MTZ004-021045-
/O.CON.KMSO.WS.A.0006.190302T0100Z-190302T1900Z/
Lower Clark Fork Region-
333 AM MST Fri Mar 1 2019

...WINTER STORM WATCH REMAINS IN EFFECT FROM THIS EVENING THROUGH
SATURDAY MORNING...

* WHAT...Blowing and drifting snow possible followed by low wind
  chills. Total new snow accumulations of up to two inches 
  possible.

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

* WHEN...From this evening through Saturday morning.

* ADDITIONAL DETAILS...Plan on slippery road conditions. The 
  cold wind chills as low as 15 below zero could result in 
  hypothermia if precautions are not taken.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Watch means there is potential for significant
snow, sleet or ice accumulations that may impact travel. Continue
to monitor the latest forecasts. 

&&

$$
3 follow-up statements
033 
WWUS45 KMSO 011838
WSWMSO

URGENT - WINTER WEATHER MESSAGE
National Weather Service Missoula MT
1138 AM MST Fri Mar 1 2019

MTZ005-021900-
/O.UPG.KMSO.WS.A.0006.190302T0100Z-190302T1900Z/
/O.EXB.KMSO.WS.W.0010.190302T0100Z-190302T1900Z/
Missoula/Bitterroot Valleys-
1138 AM MST Fri Mar 1 2019

...WINTER STORM WARNING IN EFFECT FROM 6 PM THIS EVENING TO NOON
MST SATURDAY...

* WHAT...Blowing and drifting snow followed by extremely cold wind
  chills expected. Total snow accumulations of up to one inch 
  expected.

* WHERE...Missoula/Bitterroot Valleys.

* WHEN...From 6 PM this evening to noon MST Saturday.

* ADDITIONAL DETAILS...Travel could become very difficult due to
  deep snow drifts over roadways. Areas of blowing snow could 
  significantly reduce visibility. Dangerously cold wind chills as
  low as 20 below zero could cause frostbite on exposed skin in 
  as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for blowing snow means severe winter 
weather conditions will make travel very hazardous or impossible. 
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.

&&

$$

MTZ004-021900-
/O.UPG.KMSO.WS.A.0006.190302T0100Z-190302T1900Z/
/O.EXB.KMSO.WS.W.0010.190302T0100Z-190302T1900Z/
Lower Clark Fork Region-
1138 AM MST Fri Mar 1 2019

...WINTER STORM WARNING IN EFFECT FROM 6 PM THIS EVENING TO NOON
MST SATURDAY...

* WHAT...Blowing and drifting snow followed by extremely cold wind
  chills expected. Total snow accumulations of up to two inches 
  expected.

* WHERE...Evaro Hill, Highway 200 Thompson Falls to Plains, I90
  Superior to Missoula.

* WHEN...From 6 PM this evening to noon MST Saturday.

* ADDITIONAL DETAILS...Travel could become very difficult due to
  deep snow drifts over roadways, particularly for areas east of
  Superior. Areas of blowing snow could significantly reduce 
  visibility. Dangerously cold wind chills as low as 20 below zero
  could cause frostbite on exposed skin in as little as 30 
  minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for blowing snow means severe winter 
weather conditions will make travel very hazardous or impossible. 
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.

&&

$$

MTZ002-021900-
/O.CON.KMSO.WS.W.0010.000000T0000Z-190302T1900Z/
West Glacier Region-
1138 AM MST Fri Mar 1 2019

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON MST
SATURDAY...

* WHAT...Blowing and drifting snow followed by extremely cold 
  wind chills expected. Total snow accumulations of 4 to 6 
  inches expected.

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

* WHEN...From 6 AM this morning to noon MST Saturday.

* ADDITIONAL DETAILS...Travel could be very difficult. Areas of 
  blowing snow could significantly reduce visibility. The 
  dangerously cold wind chills as low as 40 below zero could 
  cause frostbite on exposed skin in as little as 10 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for blowing snow means severe winter 
weather conditions will make travel very hazardous or impossible. 
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.

&&

$$

MTZ003-021900-
/O.CON.KMSO.WS.W.0010.000000T0000Z-190302T1900Z/
Flathead/Mission Valleys-
1138 AM MST Fri Mar 1 2019

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON MST
SATURDAY...

* WHAT...Blowing and drifting snow followed by extremely cold 
  wind chills expected. Total snow accumulations of 1 to 3 
  inches expected.

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

* WHEN...From 10 AM this morning to noon MST Saturday.

* ADDITIONAL DETAILS...Travel could be very difficult due to
  drifting snow across roadways. Areas of blowing snow could 
  significantly reduce visibility. The cold wind chills as low as 
  20 below zero could cause frostbite on exposed skin in as little
  as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for blowing snow means severe winter 
weather conditions will make travel very hazardous or impossible. 
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.

&&

$$

MTZ007-043-021900-
/O.CON.KMSO.WS.W.0010.000000T0000Z-190302T1900Z/
Butte/Blackfoot Region-Potomac/Seeley Lake Region-
1138 AM MST Fri Mar 1 2019

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON MST
SATURDAY...

* WHAT...Blowing and drifting snow followed by extremely cold 
  wind chills. Total snow accumulations of 1 to 3 inches 
  expected.

* WHERE...Georgetown Lake, Highway 12 Garrison to Elliston, 
  Homestake Pass, MacDonald Pass, Highway 200 Bonner to 
  Greenough, and I-90 East Missoula to Bearmouth.

* WHEN...From 10 AM this morning to noon MST Saturday.

* ADDITIONAL DETAILS...Travel could be very difficult due to
  drifting snow across roadways. Areas of blowing snow could 
  significantly reduce visibility. 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...

A Winter Storm Warning for blowing snow means severe winter 
weather conditions will make travel very hazardous or impossible. 
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.

&&

$$

MTZ006-021900-
/O.UPG.KMSO.WS.A.0006.190301T1900Z-190302T1900Z/
/O.NEW.KMSO.WW.Y.0032.190301T1900Z-190302T1900Z/
Bitterroot/Sapphire Mountains-
1138 AM MST Fri Mar 1 2019

...WINTER WEATHER ADVISORY IN EFFECT UNTIL NOON MST SATURDAY...

* WHAT...Snow and blowing snow expected followed by dangerous wind
  chills. Total snow accumulations of 1 to 3 inches expected.

* WHERE...Bitterroot/Sapphire Mountains.

* WHEN...Until noon MST Saturday.

* ADDITIONAL DETAILS...Plan on slippery road conditions. The 
  cold wind chills as low as 20 below zero could cause frostbite 
  on exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow and blowing snow means periods
of snow will cause primarily travel difficulties. Expect snow 
covered roads and limited visibilities, and use caution while 
driving. 

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

&&

$$

MTZ001-021900-
/O.NEW.KMSO.WW.Y.0032.190302T0100Z-190302T1900Z/
Kootenai/Cabinet Region-
1138 AM MST Fri Mar 1 2019

...WINTER WEATHER ADVISORY IN EFFECT FROM 6 PM THIS EVENING TO
NOON MST SATURDAY...

* WHAT...Snow and blowing snow expected. Total snow accumulations
  of 1 to 3 inches expected.

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

* WHEN...From 6 PM this evening to noon MST Saturday.

* ADDITIONAL DETAILS...Plan on slippery road conditions. Blowing
  snow will lower visibility at times and may cause drifting in
  localized areas. The cold wind chills as low as 20 below zero 
  could cause frostbite on exposed skin in as little as 30 
  minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow and blowing snow means periods
of snow will cause primarily travel difficulties. Expect snow 
covered roads and limited visibilities, and use caution while 
driving. 

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

&&

$$
830 
WWUS45 KMSO 012148
WSWMSO

URGENT - WINTER WEATHER MESSAGE
National Weather Service Missoula MT
248 PM MST Fri Mar 1 2019

MTZ002-021900-
/O.NEW.KMSO.WC.A.0001.190303T0400Z-190303T1500Z/
/O.CON.KMSO.WS.W.0010.000000T0000Z-190302T1900Z/
West Glacier Region-
248 PM MST Fri Mar 1 2019

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON MST
SATURDAY...
...WIND CHILL WATCH IN EFFECT FROM SATURDAY EVENING THROUGH
SUNDAY MORNING...

* WHAT...Blowing and drifting snow followed by extremely cold wind
  chills expected. Total new snow accumulations of 4 to 6 inches
  expected. Winds gusting as high as 35 mph. Wind chills as low as
  50 below zero possible late Saturday night through Sunday
  morning.

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

* WHEN...For the Winter Storm Warning, until noon MST Saturday. 
  For the Wind Chill Watch, from Saturday evening through Sunday 
  morning.

* ADDITIONAL DETAILS...Plan on slippery road conditions. Areas 
  of blowing snow could significantly reduce visibility. The 
  dangerously cold wind chills could cause frostbite on exposed 
  skin in as little as 10 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for blowing and drifting snow means severe
winter weather conditions will make travel very hazardous or 
impossible. If you must travel, keep an extra flashlight, food and
water in your vehicle in case of an emergency. 

A Wind Chill Watch means there is the potential for a combination
of very cold air and the wind to create dangerously low wind
chill values. Monitor the latest forecasts and warnings for
updates on this situation. 

&&

$$

MTZ003-021900-
/O.NEW.KMSO.WC.A.0001.190303T0400Z-190303T1500Z/
/O.CON.KMSO.WS.W.0010.000000T0000Z-190302T1900Z/
Flathead/Mission Valleys-
248 PM MST Fri Mar 1 2019

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON MST
SATURDAY...
...WIND CHILL WATCH IN EFFECT FROM SATURDAY EVENING THROUGH
SUNDAY MORNING...

* WHAT...Blowing and drifting snow followed by extremely cold wind
  chills expected. Total new snow accumulations of 1 to 3 inches
  expected. Winds gusting as high as 40 mph. Wind chills as low as
  35 below zero possible late Saturday night through Sunday
  morning.

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

* WHEN...For the Winter Storm Warning, until noon MST Saturday. 
  For the Wind Chill Watch, from Saturday evening through Sunday 
  morning.

* ADDITIONAL DETAILS...Plan on slippery road conditions. Areas 
  of blowing snow could significantly reduce visibility. The 
  dangerously cold wind chills could cause frostbite on exposed 
  skin in as little as 10 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for blowing and drifting snow means severe
winter weather conditions will make travel very hazardous or 
impossible. If you must travel, keep an extra flashlight, food and
water in your vehicle in case of an emergency. 

A Wind Chill Watch means there is the potential for a combination
of very cold air and the wind to create dangerously low wind
chill values. Monitor the latest forecasts and warnings for
updates on this situation. 

&&

$$

MTZ007-021900-
/O.NEW.KMSO.WC.A.0001.190303T0400Z-190303T1500Z/
/O.CON.KMSO.WS.W.0010.000000T0000Z-190302T1900Z/
Butte/Blackfoot Region-
248 PM MST Fri Mar 1 2019

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON MST
SATURDAY...
...WIND CHILL WATCH IN EFFECT FROM SATURDAY EVENING THROUGH
SUNDAY MORNING...

* WHAT...Blowing and drifting snow followed by extremely cold wind
  chills. Total new snow accumulations of 1 to 3 inches expected.
  Wind chills as low as 55 below zero possible late Saturday 
  night through Sunday morning.

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

* WHEN...For the Winter Storm Warning, until noon MST Saturday. 
  For the Wind Chill Watch, from Saturday evening through Sunday 
  morning.

* ADDITIONAL DETAILS...Plan on slippery road conditions. The 
  dangerously cold wind chills could cause frostbite on exposed 
  skin in as little as 5 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for blowing and drifting snow means severe
winter weather conditions will make travel very hazardous or 
impossible. If you must travel, keep an extra flashlight, food and
water in your vehicle in case of an emergency. 

A Wind Chill Watch means there is the potential for a combination
of very cold air and the wind to create dangerously low wind
chill values. Monitor the latest forecasts and warnings for
updates on this situation. 

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

&&

$$

MTZ043-021900-
/O.NEW.KMSO.WC.A.0001.190303T0400Z-190303T1500Z/
/O.CON.KMSO.WS.W.0010.000000T0000Z-190302T1900Z/
Potomac/Seeley Lake Region-
248 PM MST Fri Mar 1 2019

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON MST
SATURDAY...
...WIND CHILL WATCH IN EFFECT FROM SATURDAY EVENING THROUGH
SUNDAY MORNING...

* WHAT...Blowing and drifting snow followed by extremely cold wind
  chills. Total new snow accumulations of 2 to 4 inches expected.
  Wind chills as low as 50 below zero possible late Saturday 
  night through Sunday morning.

* WHERE...Highway 200 Bonner to Greenough, Highway 83 Seeley 
  Lake to Condon, and I-90 East Missoula to Bearmouth.

* WHEN...For the Winter Storm Warning, until noon MST Saturday. 
  For the Wind Chill Watch, from Saturday evening through Sunday 
  morning.

* ADDITIONAL DETAILS...Plan on slippery road conditions. The 
  dangerously cold wind chills could cause frostbite on exposed 
  skin in as little as 10 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for blowing and drifting snow means severe
winter weather conditions will make travel very hazardous or 
impossible. If you must travel, keep an extra flashlight, food and
water in your vehicle in case of an emergency. 

A Wind Chill Watch means there is the potential for a combination
of very cold air and the wind to create dangerously low wind
chill values. Monitor the latest forecasts and warnings for
updates on this situation. 

&&

$$

MTZ005-021900-
/O.CON.KMSO.WS.W.0010.190302T0100Z-190302T1900Z/
Missoula/Bitterroot Valleys-
248 PM MST Fri Mar 1 2019

...WINTER STORM WARNING REMAINS IN EFFECT FROM 6 PM THIS EVENING
TO NOON MST SATURDAY...

* WHAT...Blowing and drifting snow followed by extremely cold wind
  chills expected. Total new snow accumulations of up to one inch
  expected.

* WHERE...Missoula/Bitterroot Valleys.

* WHEN...From 6 PM this evening to noon MST Saturday.

* ADDITIONAL DETAILS...Travel could become very difficult due to 
  deep snow drifts over roadways. Areas of blowing snow could 
  significantly reduce visibility. Dangerously cold wind chills 
  as low as 20 below zero could cause frostbite on exposed skin 
  in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for blowing and drifting snow means severe
winter weather conditions will make travel very hazardous or 
impossible. 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.

&&

$$

MTZ004-021900-
/O.CON.KMSO.WS.W.0010.190302T0100Z-190302T1900Z/
Lower Clark Fork Region-
248 PM MST Fri Mar 1 2019

...WINTER STORM WARNING REMAINS IN EFFECT FROM 6 PM THIS EVENING
TO NOON MST SATURDAY...

* WHAT...Blowing and drifting snow followed by extremely cold wind
  chills expected. Total new snow accumulations of up to two 
  inches expected.

* WHERE...Evaro Hill, Highway 200 Thompson Falls to Plains, I90 
  Superior to Missoula.

* WHEN...From 6 PM this evening to noon MST Saturday.

* ADDITIONAL DETAILS...Travel could become very difficult due to 
  deep snow drifts over roadways, particularly for areas east of 
  Superior. Areas of blowing snow could significantly reduce 
  visibility. Dangerously cold wind chills as low as 20 below 
  zero could cause frostbite on exposed skin in as little as 30 
  minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for blowing snow means severe winter
weather conditions will make travel very hazardous or impossible.
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.

&&

$$

MTZ001-021900-
/O.CON.KMSO.WW.Y.0032.190302T0100Z-190302T1900Z/
Kootenai/Cabinet Region-
248 PM MST Fri Mar 1 2019

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM THIS
EVENING TO NOON MST SATURDAY...

* WHAT...Snow and blowing snow expected. Total snow 
  accumulations of 1 to 3 inches expected.

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

* WHEN...From 6 PM this evening to noon MST Saturday.

* ADDITIONAL DETAILS...Plan on slippery road conditions. Blowing 
  snow will lower visibility at times and may cause drifting in 
  localized areas. The cold wind chills as low as 20 below zero 
  could cause frostbite on exposed skin in as little as 30 
  minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow and blowing snow means periods
of snow will cause primarily travel difficulties. Expect snow
covered roads and limited visibilities, and use caution while
driving.

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

&&

$$

MTZ006-021900-
/O.CON.KMSO.WW.Y.0032.000000T0000Z-190302T1900Z/
Bitterroot/Sapphire Mountains-
248 PM MST Fri Mar 1 2019

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL NOON MST
SATURDAY...

* WHAT...Snow and blowing snow expected followed by dangerous 
  wind chills. Total snow accumulations of 1 to 3 inches 
  expected.

* WHERE...Bitterroot/Sapphire Mountains.

* WHEN...Until noon MST Saturday.

* ADDITIONAL DETAILS...Plan on slippery road conditions. The 
  cold wind chills as low as 20 below zero could cause frostbite 
  on exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow and blowing snow means periods
of snow will cause primarily travel difficulties. Expect snow
covered roads and limited visibilities, and use caution while
driving.

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

&&

$$
617 
WWUS45 KMSO 021644
WSWMSO

URGENT - WINTER WEATHER MESSAGE
National Weather Service Missoula MT
944 AM MST Sat Mar 2 2019

MTZ007-031645-
/O.CAN.KMSO.WS.W.0010.000000T0000Z-190302T1900Z/
/O.UPG.KMSO.WC.A.0001.190303T0400Z-190303T1500Z/
/O.NEW.KMSO.WC.W.0004.190302T1644Z-190303T1800Z/
Butte/Blackfoot Region-
944 AM MST Sat Mar 2 2019

...WIND CHILL WARNING IN EFFECT UNTIL 11 AM MST SUNDAY...
...WINTER STORM WARNING IS CANCELLED...

* WHAT...Dangerously cold wind chills occurring. Wind chills as
  cold as 40 to 50 below zero, especially tonight into early
  Sunday morning. Drifting snow will continue, especially tonight.
  Snow showers will produce up to 1 inch of additional snowfall.

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

* WHEN...Until 11 AM MST Sunday.

* ADDITIONAL DETAILS...The dangerously cold wind chills could
  cause frostbite on exposed skin in as little as 5 minutes.
  Drifting snow on roadways may make travel difficult in local 
  areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Wind Chill Warning means the combination of very cold air and
the wind will create dangerously low wind chill values. Frostbite
can occur quickly and even hypothermia or death if precautions
are not taken. 

&&

$$

MTZ003-031500-
/O.CAN.KMSO.WS.W.0010.000000T0000Z-190302T1900Z/
/O.UPG.KMSO.WC.A.0001.190303T0400Z-190303T1500Z/
/O.NEW.KMSO.WC.W.0004.190303T0600Z-190303T1500Z/
Flathead/Mission Valleys-
944 AM MST Sat Mar 2 2019

...WIND CHILL WARNING IN EFFECT FROM 11 PM THIS EVENING TO 8 AM
MST SUNDAY...
...WINTER STORM WARNING IS CANCELLED...

* WHAT...Dangerously cold wind chills expected. Wind chills as 
  low as 35 below zero expected.

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

* WHEN...From 11 PM this evening to 8 AM MST Sunday.

* ADDITIONAL DETAILS...The dangerously cold wind chills could 
  cause frostbite on exposed skin in as little as 10 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Wind Chill Warning means the combination of very cold air and
the wind will create dangerously low wind chill values. Frostbite
can occur quickly and even hypothermia or death if precautions
are not taken. 

&&

$$

MTZ002-043-031645-
/O.CAN.KMSO.WS.W.0010.000000T0000Z-190302T1900Z/
/O.UPG.KMSO.WC.A.0001.190303T0400Z-190303T1500Z/
/O.NEW.KMSO.WC.W.0004.190303T0000Z-190303T1800Z/
West Glacier Region-Potomac/Seeley Lake Region-
944 AM MST Sat Mar 2 2019

...WIND CHILL WARNING IN EFFECT FROM 5 PM THIS AFTERNOON TO 11 AM
MST SUNDAY...
...WINTER STORM WARNING IS CANCELLED...

* WHAT...Dangerously cold wind chills expected. Wind chills as low
  as 30 to 40 below zero expected, down to 50 below zero in the
  higher terrain.

* WHERE...Bad Rock Canyon, Essex, Highway 83 Bigfork to Swan 
  Lake, Marias Pass, Polebridge, Highway 200 Bonner to 
  Greenough, Highway 83 Seeley Lake to Condon, and I-90 East 
  Missoula to Bearmouth.

* WHEN...From 5 PM this afternoon to 11 AM MST Sunday.

* ADDITIONAL DETAILS...The dangerously cold wind chills could 
  cause frostbite on exposed skin in as little as 10 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Wind Chill Warning means the combination of very cold air and
the wind will create dangerously low wind chill values. Frostbite
can occur quickly and even hypothermia or death if precautions
are not taken. 

&&

$$

MTZ005-031500-
/O.CAN.KMSO.WS.W.0010.000000T0000Z-190302T1900Z/
/O.NEW.KMSO.WC.W.0004.190303T0900Z-190303T1500Z/
Missoula/Bitterroot Valleys-
944 AM MST Sat Mar 2 2019

...WIND CHILL WARNING IN EFFECT FROM 2 AM TO 8 AM MST SUNDAY...
...WINTER STORM WARNING IS CANCELLED...

* WHAT...Dangerously cold wind chills expected. Wind chills as low
  as 30 below zero expected. Snow showers in the southern
  Bitterroot Valley could produce up to 1 inch of additional
  snowfall.

* WHERE...Missoula/Bitterroot Valleys.

* WHEN...From 2 AM to 8 AM MST Sunday.

* ADDITIONAL DETAILS...The cold wind chills could cause 
  frostbite on exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Wind Chill Warning means the combination of very cold air and
the wind will create dangerously low wind chill values. Frostbite
can occur quickly and even hypothermia or death if precautions
are not taken. 

&&

$$

MTZ004-021745-
/O.CAN.KMSO.WS.W.0010.000000T0000Z-190302T1900Z/
Lower Clark Fork Region-
944 AM MST Sat Mar 2 2019

...WINTER STORM WARNING IS CANCELLED...

Winds continue to relax, which will minimize blowing and drifting
snow to more localized areas.

$$

MTZ001-006-021745-
/O.CAN.KMSO.WW.Y.0032.000000T0000Z-190302T1900Z/
Kootenai/Cabinet Region-Bitterroot/Sapphire Mountains-
944 AM MST Sat Mar 2 2019

...WINTER WEATHER ADVISORY IS CANCELLED...

Winds continue to relax, which will minimize blowing and drifting
snow to more localized areas.

$$

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 Missoula, MT wrote its last area forecast discussion before this winter storm warning went out at Mar 1, 3:32 AM MST, 1 minute earlier.

Area forecast discussion, Mar 1, 3:32 AM MST, 1 minute before
Area Forecast Discussion
National Weather Service Missoula MT
332 AM MST Fri Mar 1 2019

...BLOWING AND DRIFTING SNOW FOLLOWED BY EXTREMELY COLD WIND
CHILLS ALONG THE CONTINENTAL DIVIDE THROUGH SATURDAY...

.DISCUSSION...The forecast remains on track for the next arctic
front to arrive in western Montana today. It will move into the
state from Canada near Glacier Park and slide down the front
range. This is a very strong, very cold high pressure system which
has prompted us to issue warnings for our zones along the
Continental Divide. This system will unfold in 5 steps in
northwest Montana:

1) Deep, fresh snow already on the ground from recent systems.
2) 2-4 inches of new, powdery snow in northwest Montana.
3) Strong east winds 20-30 mph.
4) Blowing and drifting snow causing whiteout conditions at times.
5) Very cold temperatures causing very cold wind chills.
6) Very, very cold temperatures Monday, Tuesday, and Wednesday mornings.

The rest of western Montana will see around half an inch of new
snow with strong winds and very cold temperatures at least 20
degrees below average for the next few days. While this is
certainly extreme conditions, especially for this time of year, it
is not unprecedented. Looking back through the records for more
than a century there have been several occurrences of systems this
cold in late February and early March. So it is likely we will
see some daily records set, but unlikely that we will break the
record lows for the entire month of March.

Central Idaho will also be much colder than average, but is not
expected to receive much if any snow from this system.

Models agree well also on another system bringing snow to the
region Wednesday night into Thursday. At a time of year we might
expect some rain though, the temperatures remain cold enough that
Montana should experience all snow, whereas in central Idaho
there will be some rain mixed in.

&&

.AVIATION...Clear skies last night has allowed for the development
of patchy freezing fog throughout the Northern Rockies. This fog
will dissipate by mid to late morning and potentially impact KMSO
and KBTM. A subtle feature is dropping out of Alberta Canada this
morning causing light snow over KGPI. A secondary system swings
through the region from the west later today causing scattered
showers over the remainder of the region. The biggest concern will
be the strong arctic airmass that will blast through the region
from the north and east. KGPI will be first impacted as wind gusts
over 30 mph and enhanced snow is expected around 01/15z. The
arctic will push into KMSO and KBTM around 02/00z. Blowing and
drifting snow will also be an issue as this arctic impacts the
region.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...Winter Storm Warning from 10 AM this morning to noon MST
     Saturday Butte/Blackfoot Region...Potomac/Seeley Lake
     Region.

     Winter Storm Watch from noon MST today through Saturday morning
     Bitterroot/Sapphire Mountains.

     Winter Storm Watch from this evening through Saturday morning
     Missoula/Bitterroot Valleys.

     Winter Storm Watch from this evening through Saturday morning
     Lower Clark Fork Region.

     Winter Storm Warning from 10 AM this morning to noon MST
     Saturday Flathead/Mission Valleys.

     Winter Storm Warning from 6 AM this morning to noon MST Saturday
     West Glacier Region.

ID...None.
&&

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 1, 11:38 AM MSTWinter Weather AdvisoryMSOFlathead, Granite, Lincoln, Missoula, Ravalli, Sanders22 hr
Mar 1, 2:48 PM MSTWind Chill WatchMSODeer Lodge, Flathead, Granite, Lake, Missoula, Powell and 2 more19 hr

Nearby

Winter Storm Warnings in Montana, 2019Every winter storm warning in 2019

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.