Atmospheric conditions favored the downward mixing of higher winds from above as a very strong pacific jet stream emerged eastward over the continental divide. Some funneling was noted, especially along the higher terrain near the Little Rocky Mountains.
Every event with a place to put it; 9 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 GGW wrote it up.
Atmospheric conditions favored the downward mixing of higher winds from above as a very strong pacific jet stream emerged eastward over the continental divide. Some funneling was noted, especially along the higher terrain near the Little Rocky Mountains.
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 Glasgow, MT wrote its last area forecast discussion before the first event at Dec 28, 4:03 AM MST, 4 hours 15 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT 403 AM MST WED DEC 28 2011 .SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH FRIDAY... WINDS WILL BE THE MAIN CONCERN THROUGH THE SHORT TERM WITH STRONG WESTERLY FLOW AND EMBEDDED SHORTWAVES ACROSS MONTANA. SOME PRECIPITATION MAINLY IN THE FORM OF RAIN IS POSSIBLE WITH THE SHORTWAVE...BUT THE STRONG DOWNSLOPE FLOW SHOULD KEEP ACCUMULATIONS LOW. WARM FRONT LIFTING ACROSS MONTANA THIS MORNING...WITH CLOUDS SPREADING EASTWARD. SOME PRECIPITATION POSSIBLE WITH THIS FRONT THROUGH THE MORNING AND EARLY AFTERNOON. NOSE OF THE JET PUSHES ACROSS THE DIVIDE AND DOWNSLOPE WINDS EXPECTED TO KICK IN LATER THIS MORNING. MODELS BRING A 50 KT 850 JET ACROSS MONTANA TODAY BUT WITH WARM AIR ADVECTION LOW LEVEL LAPSE RATE STAY VERY LOW AND DO NOT EXPECT MUCH MIXING OF BOUNDARY LAYER. EXCEPTION WILL BE IN SOUTHWEST PHILLIPS COUNTY WHERE HIGHER TERRAIN WILL INTERSECT THE 850 JET...SO HAVE UPGRADED HIGH WIND WATCH TO A WARNING FOR THE AREA AROUND THE LITTLE ROCKIES. ANOTHER SHORTWAVE PUSHES THROUGH MONTANA ON THURSDAY. SIMILAR CONDITIONS EXPECTED WITH 50 KT 850 JET CROSSING THE REGION IN THE AFTERNOON. MAIN DIFFERENCE FROM TODAY IS THAT COLD AIR ADVECTION IS EXPECTED...WHICH WILL INCREASE LAPSE RATES AND AID MOMENTUM TRANSFER. BEST MIXING IS EXPECTED ACROSS THE SOUTHWEST HALF OF THE CWA ALONG WITH THE 700MB JET. MODELS DIFFERING SLIGHTLY ON THE POSITION OF THE 850 JET BUT WILL GO AHEAD AND ISSUE HIGH WIND WATCH FOR THE SOUTHERN ZONES FOR THURSDAY. FRIDAY WILL SEE A SLIGHT RIDGE BEGIN TO DEVELOP OVER MONTANA AND STRONG WARM AIR ADVECTION. THIS WILL KEEP LAPSE RATES LOW WITH POOR MIXING AND SLOW REBOUND OF TEMPERATURES. EBERT .LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY... THE LONG TERM FORECAST WILL CONTINUE TO BE CHALK FULL OF ABOVE NORMAL TEMPERATURES. THE EXCEPTION WILL BE FRIDAY INTO THIS WEEKEND AS A SHORTWAVE WILL PUSH A WARM FRONT TROUGH EASTERN MONTANA AND THEN DROP A STRONG COLD FRONT THROUGH THE REGION SATURDAY AFTERNOON. WARM FRONT COLD FRONT COMBO AHEAD OF THIS WEAVE WILL BE A FAIRLY DRY FEATURE. NOT A WHOLE LOT OF QPF IN THE MODELS BUT THERE IS SOME INITIALLY FRIDAY EVENING AND FRIDAY NIGHT. HAVE A SLIGHT CHANCE OF A RAIN/SNOW MIX IN THE FORECAST FOR FRIDAY NIGHT. THE QPF IS MUCH LESS ON SATURDAY AND SATURDAY NIGHT AHEAD AND JUST BEHIND THE COLD FRONT SO DECIDED TO GO WITH SNOW FLURRIES. ANOTHER POTENTIAL MAJOR HIGH WIND EVENT WITH THE COLD FRONT ON SATURDAY AS MODELS INDICATE GOOD COLD AIR ADVECTION BEHIND THE FRONT. 850 TEMPERATURES WILL DROP FROM AROUND 2*C ABOVE SATURDAY MORNING TO -12*C SUNDAY MORNING. MODELS FORECAST WINDS UP TO 70 KT AT 850 MB ARE LIKELY TO MIX TO THE SURFACE WITH THIS COLD AIR ADVECTION. AFTER SUNDAY THINGS WILL DRY OUT AS THE MODELS SHOW A LARGE AMPLIFIED UPPER LEVEL RIDGE MOVING OVER EASTERN MONTANA LATE ON MONDAY. THE MODELS ARE IN PRETTY GOOD AGREEMENT ON THIS FEATURE SO THE FIRST WEEK OF THE NEW YEAR WILL BE VERY MILD. 850 MB TEMPERATURES WILL REMAIN IN THE 4*C TO 11*C ABOVE ZERO WHICH FROM MONDAY NIGHT THROUGH THE END OF NEXT WEEK. WEDNESDAY AND THURSDAY HIGHS COULD BE IN THE MID TO UPPER 50S WHICH IN SOME CASES MAY BREAK FEW RECORD HIGH TEMPERATURE READING FOR THOSE DAYS. RSMITH && .AVIATION... VFR CONDITIONS WITH CEILINGS DOWN TO 4K FT AGL AT TIMES TODAY. ANY PRECIPITATION THAT DOES FALL WILL BE IN THE FORM OF RAIN TODAY. EXPECT THE WINDS TO INCREASE FROM WEST SOUTHWEST AT 15 TO 30 KNOTS AT ALL TERMINALS. THE WINDS WILL DECREASE AT ALL TERMINALS AFTER SUNSET. RSMITH && .GLASGOW WATCHES/WARNINGS/ADVISORIES... HIGH WIND WATCH FROM THURSDAY MORNING THROUGH THURSDAY AFTERNOON FOR CENTRAL AND SOUTHEAST PHILLIPS...PETROLEUM...GARFIELD... MCCONE...DAWSON...PRAIRIE...WIBAUX...SOUTHWEST PHILLIPS. HIGH WIND WARNING UNTIL 6 PM MST THIS EVENING FOR SOUTHWEST PHILLIPS. && WEATHER.GOV/GLASGOW
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GLASGOW MT 345 AM MST WED DEC 28 2011 MTZ017>020-024-059-061-062-291045- CENTRAL AND SOUTHERN VALLEY-DANIELS-SHERIDAN-WESTERN ROOSEVELT- RICHLAND-NORTHERN PHILLIPS-NORTHERN VALLEY-EASTERN ROOSEVELT- 345 AM MST WED DEC 28 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...TODAY AND TONIGHT NO HAZARDOUS WEATHER EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY WINDY CONDITIONS ARE EXPECTED ON THURSDAY. WEST WINDS OF 25 TO 35 MPH WITH GUSTS TO AS HIGH AS 50 MPH ARE POSSIBLE THURSDAY AFTERNOON. WINDY CONDITIONS ARE ALSO EXPECTED AGAIN ON SATURDAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ060-291045- SOUTHWEST PHILLIPS- 345 AM MST WED DEC 28 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...TODAY AND TONIGHT A HIGH WIND WARNING IS IN EFFECT FOR THIS AFTERNOON. WEST WINDS OF 30 TO 40 MPH WITH GUSTS TO 60 MPH ARE POSSIBLE. WINDS ARE EXPECTED TO DIMINISH SOMEWHAT THIS EVENING. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY WINDY CONDITIONS ARE EXPECTED AGAIN ON THURSDAY AND A HIGH WIND WATCH IS IN EFFECT. WEST WINDS OF 35 TO 50 MPH WITH GUSTS TO AS HIGH AS 70 MPH ARE POSSIBLE THURSDAY AFTERNOON. WINDY CONDITIONS ARE ALSO EXPECTED ON SATURDAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ016-021>023-025>027-291045- CENTRAL AND SOUTHEAST PHILLIPS-PETROLEUM-GARFIELD-MCCONE-DAWSON- PRAIRIE-WIBAUX- 345 AM MST WED DEC 28 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...TODAY AND TONIGHT NO HAZARDOUS WEATHER EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY WINDY CONDITIONS ARE EXPECTED ON THURSDAY AND A HIGH WIND WATCH IS IN EFFECT. WEST WINDS OF 30 TO 40 MPH WITH GUSTS TO AS HIGH AS 60 MPH ARE POSSIBLE THURSDAY AFTERNOON. WINDY CONDITIONS ARE ALSO EXPECTED ON SATURDAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
The national radar mosaic for the moment the first event began.
9 high wind. Local standard time, as filed.
Sustained winds of 40 to 50 mph were common across the area with gusts near 60 mph. A peak wind gust of 65 mph was measured at the Malta South US-191 DOT site at 10:28 PM MST.
Sustained winds of 40 to 50 mph were common across the area with gusts often above 60 mph. A peak wind gust of 71 mph was measured at the Malta South US-191 DOT site at 11:24 PM MST.
Sustained winds near and above 40 mph occurred for 2 to 3 hours at the Whitewater (QWW) mesonet site.
Sustained winds of 30 to 45 mph were common across the county with a peak wind gust of 61 mph measured at the Saco US-2 DOT site at 1:20 PM MST.
Sustained winds near or above 30 mph were common over multiple hours with a peak wind gust of 57 mph sometime between 12:22 PM and 1:22 PM MST at the Chain Buttes RAWS site.
Sustained winds near and above 40 mph occurred between 1:00 PM and 3:00 PM MST at the East of Fort Peck Dam (QFP) mesonet site and between 5:30 PM and 7:00 PM MST and the Cow Creek DOT site.
Sustained winds of 30 to 40 mph were common across the county with a peak wind gust of 60 mph measured at the King Coulee RAWS site between 1:45 PM and 2:45 PM MST.
Sustained winds of 35 to 45 mph were common across the county with gusts often reaching over 50 mph both at the Dawson Community Airport KGDV AWOS site and the Lindsay Divide DOT site.
Sustained winds near and above 40 mph occurred for a few hours at the Rock Creek (QRC) mesonet site.
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, December 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: 358100, 358104, 358784, 358096, 358782, 358785, 358095, 358783, 358786.