Blizzard and Winter Storm in Montana, February 5 to 6, 2017

Name: Blizzard and Winter Storm in Montana, February 5 to 6, 2017
Start: 2017-02-05T00:00
End: 2017-02-06T11:00
Location: Montana

February 5 to 6, 2017 · NWS MSO · 5 events in 4 counties and zones

Where it happened

Every event with a place to put it; 5 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: $10,000
Crop damage: None recorded
Events: 5

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS MSO wrote it up.

A steady stream of moisture coming in from the southwest interacted with the Arctic air sliding down from Canada, and caused heavy snow and gusty easterly winds over northwest Montana. Near whiteout conditions with snowfall rates of 1 to 2 inches per hour were observed. Some places received over 30 inches of new snow. Roads become impassable at times, particularly in the Essex to Kalispell corridor during the Monday morning commute. Previous heavy snowfall that occurred Feb. 3 and 4 compounded snow removal problems in city-centers. Airport operations had difficulty keeping runways clear during this event.

What forecasters said that day

The local office's own words before the first event, 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 the first event at Feb 4, 3:20 PM MST, 8 hours 40 minutes earlier.

Area forecast discussion, Feb 4, 3:20 PM MST, 8 hours 40 minutes before

Area Forecast Discussion
National Weather Service Missoula MT
320 PM MST Sat Feb 4 2017

...ANOTHER ROUND OF SIGNIFICANT SNOWFALL TO IMPACT NORTHWEST
MONTANA SUNDAY THRU MONDAY...

.DISCUSSION...Periods of light snow will continue to fall across
much of the Northern Rockies through the rest of today and
overnight. Total accumulations will be generally light, being on
the order of 1 to 3 inches. However some locations near the Idaho
and Canadian border may see up to 5 inches by Sunday morning. And
that's when things get really interesting.

Forecast models are coming into much better focus regarding a
potentially significant period of very heavy snow that will
develop across NW Montana beginning Sunday afternoon. The synoptic
set up is, quite frankly, textbook to support heavy snowfall. The
combination of:

1. Strengthening low pressure at the surface over Eastern
Washington,
2. Deepening southwest mid-level flow responsible for transporting
relatively warm, moist air into the region,
3. An approaching dry, arctic cold front crossing the Continental
Divide,

This will all result in what could be some of the most impressive
single storm snowfall amounts thus far this winter. Snowfall
rates of 1 to 3 inches per hour for several hours are quite
possible in places like Libby, Kalispell and West Glacier with
travel significantly affected along US-2 and US-93. Valleys
throughout the Glacier region could see upwards of 3 feet with
Marias Pass tipping the scale at around 4 feet of snow! All of
this in a matter of 36 hours. Needless to say, the snowfall from
this storm will be very significant. Add in the possible
combination of wind from the arctic air mass and we may even see
blizzard like conditions for a time on Monday morning in parts of
Kalispell, US-2 and especially thru Bad Rock Canyon.

Farther to the south snowfall amounts will be much less (1 to 4
inches) as the more favorable forcing will not be present. However
this could change should the boundary between warm/moist and
arctic/dry air shift south. So please stay tuned for additional
updates.

Snowfall intensity will significantly decrease Monday night, but
not end. Persistent NW flow will keep moisture and a favorable
environment for snow showers in place thru Wednesday. The next
storm of significance is forecast to impact the Northern Rockies
on Thursday with more snowfall. However the absence of an arctic
boundary will focus the heaviest snowfall to be due to warm air
advection (warm front) followed by a more traditional cold front.
In fact, snow banding could come into play adding additional
enhancement to the snowfall potential. Thereafter cooler, showery
conditions seem to stay in the forecast leading into next weekend
with a possible drying trend by Sunday.

&&

.AVIATION...Snow will impact flight operations at KGPI for the
next several days. KMSO will see periods of mixed wintry
precipitation, transitioning back to snow overnight. KBTM will
largely be down sloped through this evening with occasional
showers developing Sunday morning. KSMN has recently begun
experiencing light freezing rain and will likely see occasional
mixed wintry precipitation overnight.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...Winter Weather Advisory until 11 AM MST Sunday
     Bitterroot/Sapphire Mountains.

     Winter Weather Advisory until 11 AM MST Sunday Lower Clark Fork
     Region.

     Winter Storm Warning until 5 PM MST this afternoon Lower Clark
     Fork Region.

     Winter Storm Warning from 11 AM Sunday to 11 PM MST Monday Lower
     Clark Fork Region.

     Winter Weather Advisory until 11 AM MST Sunday Flathead/Mission
     Valleys...Kootenai/Cabinet Region.

     Winter Storm Warning from 11 AM Sunday to 11 PM MST Monday
     Flathead/Mission Valleys...West Glacier Region.

     Winter Weather Advisory until 11 AM MST Sunday West Glacier
     Region.

     Winter Storm Warning until 5 PM MST this afternoon West Glacier
     Region.

     Winter Storm Warning from 11 AM Sunday to 11 PM MST Monday
     Kootenai/Cabinet Region.

     Winter Weather Advisory until 11 AM MST Sunday Potomac/Seeley
     Lake Region.

     Winter Storm Warning from 11 AM Sunday to 11 PM MST Monday
     Potomac/Seeley Lake Region.

ID...Winter Weather Advisory until 10 AM PST Sunday Northern
     Clearwater Mountains...Southern Clearwater Mountains.

&&

In the hours before

Local storm report, Feb 4, 6:07 PM MST, 5 hours 53 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MISSOULA MT
607 PM MST SAT FEB 4 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0545 PM     FREEZING RAIN    6 NW MISSOULA           46.92N 114.09W
02/04/2017  M0.00 INCH       MISSOULA           MT   OFFICIAL NWS OBS

            .

&&

NWS MISSOULA MT
IRIS SYSTEM

Local storm report, Feb 4, 6:17 PM MST, 5 hours 43 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MISSOULA MT
617 PM MST SAT FEB 4 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0400 PM     SNOW             3 SSE LIBBY             48.34N 115.53W
02/04/2017  E8.0 INCH        LINCOLN            MT   TRAINED SPOTTER

            ESTIMATED 2 FEET ON THE GROUND.

&&

NWS MISSOULA MT
IRIS SYSTEM

Local storm report, Feb 4, 6:22 PM MST, 5 hours 38 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MISSOULA MT
622 PM MST SAT FEB 4 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0518 PM     SNOW             2 ENE LIBBY             48.40N 115.52W
02/04/2017  M8.0 INCH        LINCOLN            MT   TRAINED SPOTTER

            18 INCHES ON THE GROUND.

&&

NWS MISSOULA MT
IRIS SYSTEM

Local storm report, Feb 4, 7:07 PM MST, 4 hours 53 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MISSOULA MT
707 PM MST SAT FEB 4 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1006 AM     SNOW             3 NNE STEVENSVILLE      46.55N 114.06W
02/04/2017  M3.0 INCH        RAVALLI            MT   NWS EMPLOYEE

            . THE DURATION OF THE SNOW EVENT WAS 18
            HOURS.

&&

NWS MISSOULA MT
IRIS SYSTEM

Local storm report, Feb 4, 7:46 PM MST, 4 hours 14 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MISSOULA MT
746 PM MST SAT FEB 4 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0743 PM     HEAVY SNOW       13 NNE HERON            48.23N 115.84W
02/04/2017  M26.0 INCH       LINCOLN            MT   TRAINED SPOTTER

            WOKE UP TO 17 INCHES THIS MORNING. 6 INCHES
            SINCE 2 PM. HEAVY SNOW HAS NOT STOPPED
            TODAY. 3.5 FEET ON THE GROUND. . THE
            DURATION OF THE HEAVY SNOW EVENT WAS 24
            HOURS.

&&

NWS MISSOULA MT
IRIS SYSTEM

Local storm report, Feb 4, 10:01 PM MST, 1 hour 59 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MISSOULA MT
1001 PM MST SAT FEB 4 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0247 PM     AVALANCHE        3 SSW GIBBONSVILLE      45.51N 113.94W
02/04/2017                   LEMHI              ID   DEPT OF HIGHWAYS

            BETWEEN S. TOWER CREEK ROAD AND HULL CREEK
            ROAD ON US-93 ABOUT 23 MILES NORTH OF
            SALMON. IT BLOCKED BOTH LANES FOR 1.5 HOURS.
            IT WAS 100 FEET WIDE AND 10 FEET HIGH. THERE
            WERE 4 LITTLE SLIDES SOUTH OF SALMON ON 93.
            MID-SLOPE TEMPS ROSE TO THE 40S WITH RAIN AT
            TIMES.

&&

NWS MISSOULA MT
IRIS SYSTEM

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

2 winter storm, 1 heavy snow, 1 blizzard, 1 avalanche. Local standard time, as filed.

Heavy Snow, Lower Clark Fork Region

When: February 5, 12:00 AM MST to February 6, 8:00 AM MST
Where: Lower Clark Fork Region forecast zone
Reported by: Public
Coordinates: 47.286, -114.685 (the zone’s center; the record gives no point)

A local ski area reported 35 inches of snow in 36 hours. The Montana Dept. of Transportation reported several accidents along I-90 during this timeframe. Schools were closed due to heavy snow and dangerous travel conditions. The heavy snow also contributed to a power outage that caused the I-90 rest areas to close on the 6th.

Winter Storm, Kootenai/Cabinet Region

When: February 5, 3:00 AM MST to February 6, 9:30 AM MST
Where: Kootenai/Cabinet Region forecast zone
Property damage: $10,000
Reported by: Emergency Manager
Coordinates: 48.171, -114.863 (the zone’s center; the record gives no point)

The emergency manager for Lincoln County estimated 30 to 36 inches of snow had fallen within 48 hours in Libby, MT. A Reverse 911 message went out to all citizens to warn them of this event. Schools were cancelled on Monday Feb. 6. This decision was made a day in advance of the predicted snowfall, which is extremely rare. The Eureka, MT AWOS showed visibility of less than 1 mile for over 8 hours during the peak of the event with periods of less than 0.25 mi visibility. Public reports put 2 day snow totals at 20 to 30 inches in Eureka, MT, depending on which part of town. Also there were reports of blowing and drifting snow between Kalispell and Eureka. The Fire Department in Bull Lake suffered a partial roof collapse from the heavy snow load. This trapped a type 6 fire engine within the building. The damage listed was an estimated amount. During the morning of the 5th there were reports of freezing rain on US-93.

Blizzard, West Glacier Region

When: February 5, 4:30 PM MST to February 6, 11:00 AM MST
Where: West Glacier Region forecast zone
Reported by: SNOTEL
Coordinates: 47.971, -114.069 (the zone’s center; the record gives no point)

US-2 over Marias Pass was closed by the Montana Department of Transportation due to impassable conditions. Severe driving conditions were issued for most highways in this portion of northwest Montana. MDT plow drivers estimated a three day snow total of 48 inches in Essex, MT. Ten foot drifts were seen in the vicinity of roads near Glacier National Park. The Flattop Mountain weather sensor in Glacier National Park reported 26 inches of snow in 24 hours. Another Department of Transportation weather sensor in Essex, MT recorded steady 30 mph winds with frequent gusts into the 40 mph range throughout the event. US-2 at milepost 153 near West Glacier was closed during the early morning hours of the 6th due to heavy snow and drifting.

Winter Storm, Flathead/Mission Valleys

When: February 5, 5:00 PM MST to February 6, 10:00 AM MST
Where: Flathead/Mission Valleys forecast zone
Reported by: Fire Department/Rescue
Coordinates: 47.872, -114.424 (the zone’s center; the record gives no point)

Glacier Park International Airport had to cancel two flights due to intense snowfall, with rates of up to 1.5 inches per hour. Winds combined with snow made it nearly impossible to de-ice planes before departure. The ASOS weather sensor at the airport recorded winds 30 mph gusting into the 40 mph range overnight. The peak wind speed was 33 mph sustained with 44 mph gusts. One airport fire crew employee was unable to get to work on time due to getting stuck in a snow drift. Ground blizzard conditions caused widespread travel impacts. A trained spotter reported glazed ice surfaces in Columbia Falls with freezing rain during the beginning of this event. The public reported very slick side roads due to freezing rain around Kalispell. This initial freezing rain made subsequent snowfall more dangerous to travelers. The US Postal Service did not deliver mail in some portions of the Flathead Valley on the 6th.

Avalanche, West Glacier Region

When: February 6, 12:00 AM MST to 1:00 AM MST
Where: West Glacier Region forecast zone
Reported by: Local Official
Coordinates: 47.971, -114.069 (the zone’s center; the record gives no point)

An avalanche covered the BNSF railway that runs parallel to US-2 near Marias Pass. Avalanche warnings and rail and road closures continued for days after the storm ended.

What these are

Heavy Snow: Snowfall reaching the local warning threshold without the other hazards of a winter storm.
Winter Storm: A storm that brought snow, sleet or freezing rain at warning levels, usually over several hours or days.
Blizzard: Sustained winds or frequent gusts of 35 mph or more with falling or blowing snow that cuts visibility below a quarter mile for three hours or longer.
Avalanche: A mass of snow sliding down a mountainside that caused a death, an injury or damage.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Montana in 2017 Every state in 2017 This day in weather history Warnings in Montana, February 2017

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 682489, 681689, 681698, 681704, 681703.