After a strong cold front moved across western Montana on the 13th, abundent moisture moved into the region from the southwest, producing heavy snowfall at the pass levels.
Every event with a place to put it; 3 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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.
The episode as NWS MSO wrote it up.
After a strong cold front moved across western Montana on the 13th, abundent moisture moved into the region from the southwest, producing heavy snowfall at the pass levels.
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 14, 4:04 AM MST, 9 hours 49 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
404 AM MST MON FEB 14 2011
.DISCUSSION...THE NORTHERN ROCKIES WILL GENERALLY BE IN BETWEEN
WEATHER FEATURES TODAY WHICH WILL LEAD TO YET ANOTHER GORGEOUS DAY
WITH ABOVE NORMAL TEMPERATURES DESPITE THE APPARENT LACK OF
SUNSHINE DUE TO INCREASING CLOUD COVER. CHANCES FOR PRECIPITATION
INCREASE THIS AFTERNOON BUT MAINLY OVER THE MOUNTAINS WHERE ONLY
VERY LIGHT AMOUNTS OF RAIN AND SNOW ARE EXPECTED. MEANWHILE THE
ATMOSPHERIC PATTERN OVER GRANGEVILLE WILL BE EXCELLENT TO ALLOW
STRONG...GUSTY MOUNTAIN TOP WINDS TO MIX TO THE SURFACE. WIND
GUSTS OVER 40 MPH WILL BE COMMON PLACE THIS AFTERNOON AND
THROUGHOUT THE EVENING AND THUS HAVE ISSUED A WIND ADVISORY FOR
THIS AREA IN EFFECT FROM 1 PM TO 10 PM PST. GUSTY WINDS WILL LIKELY
CONTINUE OVERNIGHT BUT AT THIS TIME IT APPEARS THEY WILL FALL
UNDER ADVISORY CRITERIA (GREATER THAN 40 MPH). HOWEVER THE
FAVORABLE PATTERN APPEARS TO ONCE AGAIN SET UP TUESDAY AFTERNOON
SO YET ANOTHER ADVISORY MAY BE NECESSARY.
GUSTY WINDS MAY ALSO BE AN ISSUE OVER NORTHWEST MONTANA THIS
EVENING AND OVERNIGHT AS A WARM FRONTAL FEATURE MOVES THROUGH THE
AREA. HOWEVER AT THIS TIME BELIEVE THESE WINDS WILL REMAIN BELOW
ADVISORY CRITERIA. VERY STRONG RIDGE TOP WINDS CAN BE EXPECTED
ACROSS THE ENTIRE AREA BUT ESPECIALLY ALONG THE CONTINENTAL DIVIDE
AND IN GLACIER NATIONAL PARK. WOULD NOT BE SURPRISED TO SEE GUSTS
WELL IN EXCESS OF 50 MPH TONIGHT.
TUESDAY A COLD FRONT WILL BEGIN ITS SLOW PASSAGE ACROSS THE
NORTHERN ROCKIES. HOWEVER WITH THE LOW PRESSURE CENTER REMAINING
OFF THE COAST OF WASHINGTON UNTIL LATE WEDNESDAY OR EVEN EARLY
THURSDAY...THE COLD FRONT IS FORECAST TO STALL DIRECTLY OVER
WESTERN MONTANA AND CENTRAL IDAHO. COMBINE THE STALLED FRONT WITH
A VERY STRONG UPPER LEVEL JET WHICH IS USHERING IN A STEADY DIET
OF MOISTURE AND HIGH AMOUNTS OF PRECIPITATION ARE QUITE LIKELY
ACROSS MUCH OF THE NORTHERN ROCKIES. SNOW LEVELS WILL BE VERY
TRICKY DURING THIS TIME FRAME GIVEN THAT LOCATIONS BEHIND THE
FRONT WILL SEE ALL SNOW WHILE THOSE ALONG AND AHEAD OF THE FRONT
EXPERIENCE RAIN OR A RAIN SNOW MIX. THIS SITUATION COULD SET THE
STAGE FOR A PROLONGED PRECIPITATION EVEN WHERE THE CLEARWATER AND
BITTERROOT MOUNTAINS SEE AT LEAST A FOOT OF SNOW OVER A 48 HOURS
PERIOD.
WEDNESDAY NIGHT ONWARD...THE MODELS ARE IN AGREEMENT WITH A BROAD
TROUGH SETTLING OVER THE WESTERN UNITED STATES BY THE END OF WEEK
INTO THE WEEKEND. SEVERAL DISTURBANCE WILL MOVE ACROSS THE
NORTHERN ROCKIES CAUSING A CHANCE FOR SNOW...BUT THE TIMING OF
THESE FEATURES ARE UNCERTAIN AT THIS TIME. THE ONE THING OF IMPACT
IS THE POTENTIAL OF ARCTIC AIR COMING OVER THE DIVIDE FRIDAY
THROUGH SATURDAY. THE MODELS HAVE DIFFERENT SOLUTIONS ON THE
STRENGTH OF THE ARCTIC...BUT LEANED TOWARDS THE ECMWF.
&&
.AVIATION...THE NORTHERN ROCKIES WILL BE IN BETWEEN WEATHER
SYSTEMS TODAY AND THUS EXCELLENT AVIATION CONDITIONS ARE FORECAST.
RIDGE TOP WINDS WILL BE INCREASING THROUGHOUT THE DAY AND
OVERNIGHT BUT LITTLE MORE THAN BREEZY CONDITIONS ARE EXPECTED AT
KMSO...KBTM...KSMN AND KGPI THROUGH THE NEXT TWENTY-FOUR HOURS.
&&
.MSO WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
ID...WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 10 PM PST THIS EVENING
FOR GRANGEVILLE AND VICINITY.
&&
SHORT TERM...DICKERSON
LONG TERM....SMITH
AVIATION...DICKERSONThe national radar mosaic for the moment the first event began.
3 heavy snow. Local standard time, as filed.
The SNOTEL at Lolo pass reported 7 inches of snow in 12 hours.
Chains were required over Lookout pass, with 9 inches of snow reported in 12 hours.
Snowfall was measured at 7 inches 1 miles southeast of Marion Montana.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2011Every state in 2011This day in weather historyWarnings in Montana, February 2011
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: 280093, 280094, 280099.