Winter Storm in Montana, November 17 to 19, 2011

Name: Winter Storm in Montana, November 17 to 19, 2011
Start: 2011-11-17T04:00
End: 2011-11-19T12:00
Location: Montana

November 17 to 19, 2011 · NWS TFX · 3 events in 3 counties and zones

A Pacific storm system brought heavy snow to portions of Southwest Montana. Snow amounts 0f 6 inches or more were reported.

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 3

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 TFX wrote it up.

A Pacific storm system brought heavy snow to portions of Southwest Montana. Snow amounts 0f 6 inches or more were reported.

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 Great Falls, MT wrote its last area forecast discussion before the first event at Nov 16, 9:27 PM MST, 6 hours 33 minutes earlier.

Area forecast discussion, Nov 16, 9:27 PM MST, 6 hours 33 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
927 PM MST WED NOV 16 2011

.UPDATE...
HAVE ALREADY UPDATED FORECAST GRIDS/ZONE FORECASTS...WILL UPDATE
STATE FORECASTS SHORTLY. MAIN UPDATE NEEDED TONIGHT WAS TO LOWER
TONIGHTS LOW TEMPERATURES. THINNING OF THE CLOUDINESS...A
SOMEWHAT SLOWER DEVELOPMENT OF DOWNSLOPING WINDS...AND CONTINUED
VERY LOW DEWPOINTS HAVE ALL CONTRIBUTED TO TEMPERATURES COOLING OF
SOMEWHAT RAPIDLY AFTER SUNSET. A FEW PLACES (SUCH AS LEWISTOWN)
HAVE ALREADY REACHED THEIR FORECAST LOWS. HAVE THEREFORE LOWERED
LOWS ACROSS THE ENTIRE AREA ABOUT 5 TO 10 DEGREES. AM STILL
ANTICIPATING WINDS TO DEVELOP OVERNIGHT WITH A THICKENING OF THE
CLOUD LAYER...SO AM SOMEWHAT EXPECTING THE DROP IN TEMPERATURES
TO LEVEL OFF SHORTLY AFTER MIDNIGHT. WOULD NOT BE SURPRISED TO SEE
TEMPERATURES RISING LATER TONIGHT AS THE WINDS INCREASE. ALSO
INCREASED WINDS ALONG THE RIDGE TOPS IN SOUTHWEST MONTANA WHERE
GUSTS ARE ALREADY STARTING TO INCREASE. WILL ALSO ALLOW THE
HIGHLIGHTS THAT ARE OUT TO CONTINUE AS IS. I SEE NO NEED TO
ADJUST THEM AT THIS POINT.  COULSTON

&&

.AVIATION...
UPDATED 2342Z.
STRONG WINDS ALOFT WILL INCREASE AS A LOW PRESSURE SYSTEM OVER
THE EASTERN PACIFIC MOVES EAST. WINDS ACROSS THE ROCKIES AND LEE
SLOPES WILL GUST TO 70 KTS AT TIMES AND LOCAL GUSTS OVER 50KTS
ARE EXPECTED THROUGH THE DAY ACROSS THE PLAINS. LIGHT SNOW OVER
THE ROCKIES WILL INCREASE IN INTENSITY BY MIDNIGHT AND BECOME
HEAVY AT TIMES THROUGH THURSDAY. IFR CONDS AND OBSCD TERRAIN ARE
EXPECTED AT TIMES. ELSEWHERE...VFR CONDS ARE EXPECTED THROUGH THE
NEXT 24 HOURS.

&&

.PREV DISCUSSION...
/ISSUED 443 PM MST WED NOV 16 2011/
THIS EVENING THROUGH FRIDAY EVENING...FORECAST STILL ON TRACK FOR
VERY ACTIVE WEATHER CONDITIONS THROUGH THE SHORT-TERM FORECAST
PERIOD. HIGH PRESSURE RIDGE THAT BROUGHT THE FAIR SKIES TODAY
STILL COVERS MUCH OF THE STATE BUT WILL MOVE INTO ERN MT TONIGHT.
HIGH CLOUDS ARE STARTING TO INCREASE FROM THE WEST...THE LEADING
EDGE OF THE SIGNIFICANT STORM SYSTEM THAT WILL BRING WINTER
CONDITIONS TO OUR REGION BEGINNING TOMORROW AFTN/EVE. AS THE
RIDGE AXIS MOVES EAST...WINDS OVER SOUTHWEST/CENTRAL MT WILL
SWITCH TO SOUTHWESTERLY AND STEADILY INCREASE. FORECAST MODELS
CONTINUE TO SHOW A BROAD AREA OF GUSTY WINDS AT LOW LEVELS
ALONG/NORTH OF A HELENA TO LEWISTOWN LINE...THUS HAVE UPGRADED
THE HIGH WIND WATCH FOR THE CENTRAL AND HILINE COUNTIES TO A
WARNING. WITH SNOW AND WIND ARRIVING ALONG THE ROCKY MTN FRONT
DURING THE OVERNIGHT PERIOD...HAVE ALSO UPGRADED THAT AREA TO A
WINTER STORM WARNING. AS THE FIRST OF TWO COLD FRONTS PUSHES EAST
OF THE ROCKIES THURS AFTN...RAIN/SNOW MIX WILL DEVELOP
ALONG/BEHIND THE FRONT...CHANGING OVER TO ALL SNOW BY EVE.
ACCUMULATIONS WILL GENERALLY BE LIGHT THOUGH THE HIGHWOODS AND
LITTLE BELT MTNS COULD SEE HEAVIER TERRAIN-ENHANCED SNOWFALL WITH
THE GUSTY WINDS...LEADING TO A NEW WINTER STORM WARNING THERE FOR
THURS AFTN THRU FRI. A SECOND STRONGER COLD FRONT DROPS STRAIGHT
SOUTH FROM ALBERTA EARLY FRI...BRINGING AN ARCTIC AIRMASS AND
ANOTHER ROUND OF SNOW. AS THE COLD AIR MOVES SOUTH IT WILL
ENCOUNTER ADDITIONAL MOISTURE AND ENERGY ASSOCIATED WITH THE CORE
OF THE STORM SYSTEM OVER SOUTHWEST MT...SETTING UP GOOD CHANCE
FOR SEVERAL INCHES OF SNOWFALL THERE ON FRI/SAT...LEADING TO A
NEW WINTER STORM WATCH FOR HEAVY SNOW ABOVE 5500 FT. LOWER
ELEVATIONS AROUND BOZEMAN/ENNIS/THREE FORKS COULD SEE ADVISORY-
LEVEL (3-5 INCHES) SNOWFALL AT THAT TIME. AFTER HIGHS IN THE LOW
/MID-40S TOMORROW...TEMPERATURES TURN SHARPLY COLDER BEHIND THE
SECOND FRONT WITH HIGH TEMPS REACHING ONLY INTO THE MID-TEENS
OVER THE HILINE AND CENTRAL COUNTIES. TEMPS WILL BE ABOUT 10 DEG
WARMER ACROSS THE SOUTHWEST ON FRI UNTIL THE FRONT REACHES THEM
AROUND MIDDAY. WARANAUSKAS

FRIDAY NIGHT THROUGH WEDNESDAY...A WEATHER DISTURBANCE EMBEDDED
IN THE BROAD UPPER TROUGH OVER THE WESTERN U.S. IS FORECAST TO
MOVE INTO THE FORECAST AREA FRIDAY NIGHT. MODELS DIFFER WITH THE
DETAILS OF THIS DISTURBANCE AND ALSO THE ASSOCIATED SNOW. DUE TO
THE UNCERTAINTY DECIDED TO LEAVE THE CURRENT CHANCE OF
PRECIPITATION FORECASTS ALONE FOR THIS PARTICULAR PERIOD. MODELS
DIFFER EVEN MORE WITH DETAILS OF SEVERAL MORE WEATHER
DISTURBANCES FORECAST TO AFFECT THE AREA THROUGH SUNDAY. WILL
CONTINUE WITH THE CURRENT FORECAST OF LOWER CHANCES OF SNOW IN
LINE WITH THE GFS AND ECMWF MODELS. DO NOTE THAT THE GEM
(CANADIAN) MODEL IS MUCH WETTER THAN EITHER THE ECMWF AND GFS FOR
THE SATURDAY NIGHT AND SUNDAY PERIOD BUT AT THIS TIME IT IS
CONSIDERED TO BE AN OUTLIER. THEREAFTER THE ECMWF AND GFS MODELS
HAVE NORTHWEST FLOW EARLY SUNDAY NIGHT TRANSITIONING TO A
SOUTHWEST FLOW ALOFT BY TUESDAY. MODELS DO NOT INDICATE A LOT OF
MOISTURE IN THIS FLOW MONDAY THROUGH TUESDAY AND IT APPEARS THE
ONLY THREAT FOR SNOW WILL BE OVER THE ROCKY MOUNTAIN FRONT. COULD
SEE AN INCREASE IN MOISTURE OVER THE WESTERN MOUNTAINS TOWARDS
MIDWEEK SO INCREASED THE CHANCES OF PRECIPITATION IN THIS AREA.
INHERITED WARMING TREND LATER IN THE WEEKEND THROUGH EARLY NEXT
WEEK LOOKS ON TRACK AND COULD POSSIBLY SEE EVEN WARMER
TEMPERATURES THAN CURRENTLY FORECAST. THE WARMING TREND WILL BE
AIDED BY INCREASED DOWNSLOPE WINDS OVER THE PLAINS. BLANK

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  24  43  13  18 /  10  20  20  70
CTB  18  41   6  16 /  10  20  20  40
HLN  13  42  19  23 /  20  40  20  70
BZN  13  45  21  29 /  20  50  60  70
WEY   3  31  20  27 /  50  80  90  80
DLN  13  40  20  32 /  20  50  70  70
HVR  10  45  11  22 /  10  40  10  20
LWT  11  43  15  20 /  10  20  20  50

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM 6 AM TO 10 PM MST THURSDAY BLAINE...
CASCADE...CENTRAL AND SOUTHERN LEWIS AND CLARK...CHOUTEAU...
EASTERN GLACIER...EASTERN PONDERA...EASTERN TETON...FERGUS...
HILL...JUDITH BASIN...LIBERTY...TOOLE.

WINTER STORM WARNING FROM NOON THURSDAY TO NOON MST SATURDAY FOR
ELEVATIONS ABOVE 5000 FEET FOR CASCADE...JUDITH BASIN...MEAGHER.

WINTER STORM WATCH FROM LATE THURSDAY NIGHT THROUGH SATURDAY
MORNING FOR ELEVATIONS ABOVE 5500 FEET FOR BROADWATER...FERGUS...
GALLATIN...MADISON.

WINTER STORM WARNING UNTIL 5 PM MST THURSDAY NORTHERN ROCKY
MOUNTAIN FRONT...SOUTHERN ROCKY MOUNTAIN FRONT.

&&

SHORT TERM...WARANAUSKAS/COULSTON
LONG TERM...BLANK
AVIATION...ZELZER

WEATHER.GOV/GREATFALLS

Hazardous weather outlook, Nov 16, 5:39 PM MST, 10 hours 21 minutes before

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE GREAT FALLS MT
539 PM MST WED NOV 16 2011

MTZ009-048-171400-
NORTHERN ROCKY MOUNTAIN FRONT-SOUTHERN ROCKY MOUNTAIN FRONT-
539 PM MST WED NOV 16 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL
MONTANA.

.DAY ONE...TONIGHT

A WINTER STORM WARNING IS IN EFFECT BEGINNING AT MIDNIGHT MST
TONIGHT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THE WINTER STORM WARNING IS IN EFFECT THROUGH 5 PM MST THURSDAY.

LIGHT SNOW WILL PERSIST FROM THURSDAY NIGHT INTO THE DAY ON
SATURDAY...BUT WINDS WILL DECREASE AS COLDER CANADIAN AIR MOVES
INTO THE AREA FOR THIS WEEKEND.

.SPOTTER INFORMATION STATEMENT...

ANY SPOTTER REPORTS OF HIGH WINDS OR SNOW TOTALS WILL BE GREATLY
APPRECIATED OVER THE NEXT FEW DAYS.

MTZ012-050-171400-
CASCADE-JUDITH BASIN-
539 PM MST WED NOV 16 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
MONTANA.

.DAY ONE...TONIGHT

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER THROUGH TONIGHT
IS LOW.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A HIGH WIND WARNING IS IN EFFECT FOR THURSDAY FROM 6 AM MST UNTIL
10 PM MST.

A WINTER STORM WARNING IS IN EFFECT FROM NOON MST THURSDAY THROUGH
NOON MST SATURDAY FOR ELEVATIONS ABOVE 5000 FEET.

WINDS WILL DECREASE AFTER THURSDAY AS COLDER CANADIAN AIR MOVES
INTO THE AREA FOR THIS WEEKEND.

.SPOTTER INFORMATION STATEMENT...

ANY SPOTTER REPORTS OF HIGH WINDS OR SNOW TOTALS WILL BE GREATLY
APPRECIATED OVER THE NEXT FEW DAYS.

MTZ010-011-013-044>047-049-171400-
EASTERN GLACIER-HILL-CHOUTEAU-TOOLE-LIBERTY-EASTERN PONDERA-
BLAINE-EASTERN TETON-
539 PM MST WED NOV 16 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL
MONTANA.

.DAY ONE...TONIGHT

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER THROUGH TONIGHT
IS LOW.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A HIGH WIND WARNING IS IN EFFECT FOR THURSDAY FROM 6 AM MST UNTIL
10 PM MST.

LIGHT SNOW WILL BE POSSIBLE FROM THURSDAY NIGHT INTO THE DAY ON
SATURDAY...BUT WINDS WILL DECREASE AS COLDER CANADIAN AIR MOVES
INTO THE AREA FOR THIS WEEKEND.

.SPOTTER INFORMATION STATEMENT...

ANY SPOTTER REPORTS OF HIGH WINDS OR SNOW TOTALS WILL BE GREATLY
APPRECIATED OVER THE NEXT FEW DAYS.

MTZ051-171400-
FERGUS-
539 PM MST WED NOV 16 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
MONTANA.

.DAY ONE...TONIGHT

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER THROUGH TONIGHT
IS LOW.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A HIGH WIND WARNING IS IN EFFECT FOR THURSDAY FROM 6 AM MST UNTIL
10 PM MST.

A WINTER STORM WATCH IS IN EFFECT FROM LATE THURSDAY NIGHT
THROUGH SATURDAY MORNING FOR ELEVATIONS ABOVE 5500 FEET.

WINDS WILL DECREASE AFTER THURSDAY AS COLDER CANADIAN AIR MOVES
INTO THE AREA FOR THIS WEEKEND.

.SPOTTER INFORMATION STATEMENT...

ANY SPOTTER REPORTS OF HIGH WINDS OR SNOW TOTALS WILL BE GREATLY
APPRECIATED OVER THE NEXT FEW DAYS.

MTZ054-171400-
MEAGHER-
539 PM MST WED NOV 16 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST
MONTANA.

.DAY ONE...TONIGHT

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER THROUGH TONIGHT
IS LOW.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A WINTER STORM WARNING IS IN EFFECT FROM NOON MST THURSDAY THROUGH
NOON MST SATURDAY FOR ELEVATIONS ABOVE 5000 FEET.

WINDS WILL DECREASE AFTER THURSDAY AS COLDER CANADIAN AIR MOVES
INTO THE AREA FOR THIS WEEKEND.

.SPOTTER INFORMATION STATEMENT...

ANY SPOTTER REPORTS OF HIGH WINDS OR SNOW TOTALS WILL BE GREATLY
APPRECIATED OVER THE NEXT FEW DAYS.

MTZ014-171400-
CENTRAL AND SOUTHERN LEWIS AND CLARK-
539 PM MST WED NOV 16 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST
MONTANA.

.DAY ONE...TONIGHT

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER THROUGH TONIGHT
IS LOW.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A HIGH WIND WARNING IS IN EFFECT FOR THURSDAY FROM 6 AM MST UNTIL
10 PM MST.

LIGHT SNOW WILL MOVE INTO THE AREA FOR THURSDAY NIGHT INTO THE
DAY ON SATURDAY...BUT WINDS WILL DECREASE AS COLDER CANADIAN AIR
MOVES INTO THE AREA FOR THIS WEEKEND.

.SPOTTER INFORMATION STATEMENT...

ANY SPOTTER REPORTS OF HIGH WINDS OR SNOW TOTALS WILL BE GREATLY
APPRECIATED OVER THE NEXT FEW DAYS.

MTZ015-052-053-055-171400-
MADISON-JEFFERSON-BROADWATER-GALLATIN-
539 PM MST WED NOV 16 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST
MONTANA.

.DAY ONE...TONIGHT

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER THROUGH TONIGHT
IS LOW.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A WINTER STORM WATCH IS IN EFFECT FROM LATE THURSDAY NIGHT
THROUGH SATURDAY MORNING FOR ELEVATIONS ABOVE 5500 FEET.

BREEZY WESTERLY WINDS WILL DECREASE AFTER THURSDAY AS COLDER
CANADIAN AIR MOVES INTO THE AREA FOR THIS WEEKEND.

.SPOTTER INFORMATION STATEMENT...

ANY SPOTTER REPORTS OF HIGH WINDS OR SNOW TOTALS WILL BE GREATLY
APPRECIATED OVER THE NEXT FEW DAYS.

MTZ008-171400-
BEAVERHEAD-
539 PM MST WED NOV 16 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST
MONTANA.

.DAY ONE...TONIGHT

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER THROUGH TONIGHT
IS LOW.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

WESTERLY WINDS WILL INCREASE DURING THE DAY ON THURSDAY AND
CONTINUE INTO THURSDAY NIGHT. A PERIOD OF SIGNIFICANT
ACCUMULATING SNOW WILL THEN BE POSSIBLE ACROSS SOUTHWEST MONTANA
BEGINNING THURSDAY NIGHT AND CONTINUING INTO THE DAY ON SATURDAY.
A STRONG COLD FRONT WILL MOVE THROUGH THE AREA FRIDAY
MORNING...BRINGING MUCH COLDER AIR INTO THE REGION FOR THE
WEEKEND.

.SPOTTER INFORMATION STATEMENT...

ANY SPOTTER REPORTS OF HIGH WINDS OR SNOW TOTALS WILL BE GREATLY
APPRECIATED OVER THE NEXT FEW DAYS.

In the hours before

Local storm report, Nov 17, 2:11 AM MST, 1 hour 49 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
211 AM MST THU NOV 17 2011

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

0108 AM     NON-TSTM WND GST 4 NNE MCALLISTER        45.50N 111.70W
11/17/2011  M57 MPH          MADISON            MT   DEPT OF HIGHWAYS

            57 MPH WIND GUST AT THE DOT SENSOR NEAR NORRIS HILL.
            SUSTAINED WINDS NEAR 49 MPH.

&&

BRUSDA

Local storm report, Nov 17, 2:12 AM MST, 1 hour 48 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
212 AM MST THU NOV 17 2011

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

0100 AM     NON-TSTM WND GST 8 SE EAST GLACIER PARK  48.37N 113.10W
11/17/2011  M65 MPH          GLACIER            MT   MESONET

            65 MPH WIND GUST AT THE DEEP CREEK RAWS LOCATION.

&&

BRUSDA

Event by event

3 winter storm. Local standard time, as filed.

Winter Storm, Southern Lewis and Clark

When: November 17, 4:00 AM MST to November 19, 5:19 AM MST
Where: Southern Lewis and Clark forecast zone
Reported by: Trained Spotter

Six inches of snow fell at East Helena 3WNW.

Winter Storm, Meagher

When: November 17, 4:00 AM MST to November 19, 5:19 AM MST
Where: Meagher forecast zone
Reported by: Trained Spotter

Six inches of snow fell at Neihart 21W.

Winter Storm, Gallatin

When: November 17, 12:00 PM MST to November 19, 12:00 PM MST
Where: Gallatin forecast zone
Reported by: Trained Spotter

Eight inches of snow fell at Bozeman 5SW.

What these are

Winter Storm: A storm that brought snow, sleet or freezing rain at warning levels, usually over several hours or days.

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

The same day elsewhere

Every storm in Montana in 2011 Every state in 2011 This day in weather history Warnings in Montana, November 2011

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: 352140, 352141, 352142.