A strong westerly flow aloft produced high winds along the Northern Rocky Mountain Front. Sustained winds in excess of 40 mph were reported.
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 TFX wrote it up.
A strong westerly flow aloft produced high winds along the Northern Rocky Mountain Front. Sustained winds in excess of 40 mph were reported.
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 Mar 16, 10:57 AM MST, 2 hours 11 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 1157 AM MDT WED MAR 16 2011 UPDATED AVIATION .UPDATE... UPDATED POPS AND THE WINTER WEATHER ADVISORY DROPPING SOME AREAS TO THE NORTH AS PRECIP HAS ENDED. MOIST SOUTHWESTERLY FLOW WILL CONTINUE THROUGH THE DAY SO THE CHANCE FOR PRECIP OVER THE SOUTHWEST WILL CONTINUE THROUGH TONIGHT. HAVE THUS KEPT THE WINTER WEATHER ADVISORY GOING THERE. WINDS SHOULD CONTINUE TO PICK UP THIS AFTERNOON ACROSS MUCH OF THE AREA AS WELL. && .AVIATION... UPDATED 1800Z. MOIST WEST-SOUTHWEST FLOW ALOFT CONTINUES OVER THE REGION WITH A SURFACE COLD FRONT CONTINUING TO MOVE EASTWARD ACROSS CENTRAL AND SOUTHWEST MONTANA. LIGHT SNOW OVER KBZN HAS TAPERED...HOWEVER WILL CONTINUE OVER THE MOUNTAINS WITH WIDESPREAD OBSCURATION CONTINUING. BRIEF PERIODS OF MVFR AND IFR CONDITIONS ARE POSSIBLE WITHIN RAIN AND SNOW. FROM KHLN AND POINTS NORTH...MAIN IMPACT TO AVIATION WILL BE DEVELOPING GUSTY POST-FRONTAL WEST WINDS WITH GUSTS UP TO 55KTS POSSIBLE ALONG THE ROCKY MOUNTAIN FRONT AND ADJACENT PLAINS. WINDS WILL DECREASE LATE TONIGHT WITH GENERALLY DRY CONDITIONS PERSISTING OVER NORTH-CENTRAL MONTANA DUE TO THE STRONG DOWNSLOPE WINDS. MLS && .HYDROLOGY... WARM TEMPERATURES OVER THE LAST FEW DAYS HAVE CAUSED SIGNIFICANT SNOWMELT ACROSS THE AREA. AREAS OF RURAL FLOODING HAVE DEVELOPED ACROSS NORTH CENTRAL MONTANA. MODERATE TEMPERATURES WILL CONTINUE THROUGH MIDWEEK WITH HIGHS AND LOWS GENERALLY ABOVE NORMAL. && .PREV DISCUSSION... /ISSUED 537 AM MDT WED MAR 16 2011/ TODAY THROUGH FRIDAY...AN UPPER LEVEL LOW PRESSURE TROF WILL BE OVER THE EASTERN PACIFIC THIS MORNING AND A JET IN THE SOUTHWEST FLOW AHEAD OF THIS SYSTEM WILL BE OVER THE CENTRAL ZONES THIS MORNING...DROPPING SOUTH ACROSS THE SW ZONES BY LATE AFTERNOON. COOLER AIR WILL BE MOVING INTO THE ZONES DURING THE DAY AND...DESPITE A WARM START...TEMPS WILL OVERALL BE COOLER THAN YESTERDAY. A SURFACE LOW IN ALBERTA WITH A TROF EXTENDING INTO THE CENTRAL ZONES WILL CAUSE A STRONG SURFACE PRESSURE GRADIENT TODAY ALONG THE LEE OF THE ROCKIES. SEVERAL CONFUSING SIGNALS AS THE HIGH WINDS ARE CONCERNED. THE STRONG PRESSURE GRADIENT ALONG THE LEE SLOPES OF THE ROCKIES SHOULD RELAX SOMEWHAT DURING THE AFTERNOON. THIS MAKES THE HIGH WIND CALL TRICKY SINCE THIS WILL MAINLY BE AN EVENT DRIVEN BY THE LOW LEVEL AND SURFACE WINDS. GOOD MIXING...HOWEVER...DURING THE AFTERNOON SHOULD BRING SOME HIGHER WINDS TO THE SURFACE AND THIS WILL ALSO BE AIDED BY A SHORTWAVE MOVING ACROSS THE FRONT DURING THE DAY. NAM HAS ONLY 40KT WINDS AT MID LEVELS BUT THE GFS IS STRONGER. CAN NOT OVERLOOK THE 65 KT CORE ON THE GFS PROG AND WILL UPGRADE THE HIGH WIND WATCH TO A WARNING. THE OTHER POINT OF INTEREST FOR TODAY IS THE WINTER WEATHER ADVISORY. DYNAMICS ARE RATHER SPARSE...A SERIES OF WEAK DISTURBANCES THAT KEEP UNSETTLED FLOW OVER THE WESTERN MOUNTAINS AND SOUTHWEST MONTANA THROUGH THURSDAY. PRECIP WILL DIMINISH AS A WEAK RIDGE BEGINS TO BUILD AND MOVE INTO PLACE BY FRIDAY. GOOD WARMING ON FRIDAY...ALONG WITH MOISTURE AT LOW LEVELS...SHOULD CREATE SLIGHTLY UNSTABLE CONDITIONS. ZELZER FRIDAY NIGHT THROUGH WEDNESDAY...AN INCREASINGLY UNSETTLED PATTERN DEVELOPS BY THIS WEEKEND...CONTINUING INTO NEXT WEEK AS AN UPPER LEVEL BLOCKING ANTICYCLONE...WHICH HAS BEEN IN PLACE OVER THE BERING STRAIT...MOVES OFF TO THE EAST...ALLOWING A LONGWAVE UPPER LEVEL TROUGH TO BECOME ESTABLISHED ALONG THE WEST COAST. THE FIRST PIECE OF SIGNIFICANT ENERGY TO EJECT OUT OF THE UPPER TROUGH WILL LIFT NE ACROSS THE REGION LATE SATURDAY THROUGH SATURDAY NIGHT...BRINGING A PERIOD OF WIDESPREAD PRECIPITATION TO MUCH OF THE FORECAST AREA. COLD AIR IS SOMEWHAT LIMITED WITH THIS SYSTEM WITH MOST OF THE COOLING COMING FROM ALOFT RATHER THAN THE INTRUSION OF A LOW LEVEL COLD AIRMASS. THEREFORE EXPECT SNOW LEVELS TO BEGIN ABOVE MOST VALLEYS AND PLAINS...LOWERING AS THE SYSTEM PASSES THROUGH SATURDAY NIGHT. MOIST AND SOMEWHAT UNSTABLE FLOW WITH EMBEDDED DISTURBANCES CONTINUING TO EJECT OUT OF THE TROUGH ALONG THE COAST WILL KEEP CONDITIONS UNSETTLED THROUGH THE FIRST HALF OF NEXT WEEK. SIGNIFICANT DIFFERENCES IN TIMING/TRACK/INTENSITY OF INDIVIDUAL SHORTWAVE FEATURES AT THIS TIME RANGE EXISTS AMONG THE LONGER RANGE MODELS...MAKING IT DIFFICULT TO BE MORE SPECIFIC...HOWEVER HAVE KEPT POPS ABOVE CLIMATOLOGICAL AVERAGES AND TEMPS SLIGHTLY BELOW AVERAGE FOR MUCH OF THIS PERIOD. HOENISCH && .PRELIMINARY POINT TEMPS/POPS... GTF 49 28 45 26 / 20 10 10 10 CTB 44 26 41 23 / 10 10 10 10 HLN 50 28 48 25 / 40 30 20 20 BZN 47 26 44 21 / 70 50 40 20 WEY 35 17 30 7 / 100 90 60 30 DLN 46 25 42 20 / 70 40 30 20 HVR 45 22 40 19 / 20 10 10 10 LWT 48 28 43 24 / 30 10 10 10 && .TFX WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL 6 AM MDT THURSDAY EASTERN GLACIER... NORTHERN ROCKY MOUNTAIN FRONT...SOUTHERN ROCKY MOUNTAIN FRONT. WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT BEAVERHEAD... GALLATIN...MADISON. SMALL STREAM FLOOD WARNINGS FOR SELECTED AREAS OF PONDERA...TETON...AND CHOUTEAU COUNTIES CONTINUE IN EFFECT. SMALL STREAM FLOOD ADVISORY FOR CASCADE. SMALL STREAM FLOOD ADVISORY FOR HILL AND BLAINE COUNTIES. FLOOD ADVISORY FOR ICE JAMMING AND SNOW MELT ON THE MISSOURI RIVER ALONG THE NORTHEASTERN FERGUS AND SOUTHWESTERN PHILLIPS COUNTY LINE IN CENTRAL MONTANA && WEATHER.GOV/GREATFALLS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GREAT FALLS MT 528 AM MDT WED MAR 16 2011 MTZ009>013-044>051-171230- NORTHERN ROCKY MOUNTAIN FRONT-EASTERN GLACIER-HILL-CASCADE- CHOUTEAU-TOOLE-LIBERTY-EASTERN PONDERA-BLAINE- SOUTHERN ROCKY MOUNTAIN FRONT-EASTERN TETON-JUDITH BASIN-FERGUS- 528 AM MDT WED MAR 16 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL MONTANA AND NORTH CENTRAL MONTANA. .DAY ONE...TODAY AND TONIGHT A HIGH WIND WARNING IS IN EFFECT FOR THE NORTHERN ROCKIES AND EASTERN GLACIER COUNTY THROUGH TONIGHT. FLOOD WARNINGS REMAIN IN EFFECT FOR PORTIONS OF TETON...PONDERA...AND CHOUTEAU COUNTIES. A FLOOD ADVISORY FOR MELTING SNOW IS IN EFFECT FOR PORTIONS OF CASCADE...BLAINE...AND HILL COUNTIES. A FLOOD ADVISORY FOR SNOW MELT AND ICE JAMMING FOR NORTHEASTERN FERGUS COUNTY REMAINS IN EFFECT. A WINTER WEATHER ADVISORY FOR SNOW FOR THE ROCKY MOUNTAINS IS IN EFFECT UNTIL MIDNIGHT TONIGHT FOR ELEVATIONS ABOVE 5000 FEET. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY THE FLOOD ADVISORY FOR AN ICE JAM AND SNOW MELT REMAINS IN EFFECT UNTIL 315 PM MDT THURSDAY FOR NORTHEASTERN FERGUS COUNTY. THE FLOOD ADVISORY FOR MELTING SNOW REMAINS IN EFFECT UNTIL 330 PM MDT THURSDAY FOR BLAINE AND HILL COUNTIES. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. MTZ008-014-015-052>055-171230- BEAVERHEAD-CENTRAL AND SOUTHERN LEWIS AND CLARK-MADISON-JEFFERSON- BROADWATER-MEAGHER-GALLATIN- 528 AM MDT WED MAR 16 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST MONTANA. .DAY ONE...TODAY AND TONIGHT A WINTER WEATHER ADVISORY FOR SNOW FOR PORTIONS OF SOUTHWEST MONTANA IS EFFECT UNTIL MIDNIGHT TONIGHT FOR ELEVATIONS ABOVE 5000 FEET. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE GREAT FALLS MT
1224 PM MDT WED MAR 16 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1156 AM SNOW 5 S WEST YELLOWSTONE 44.59N 111.12W
03/16/2011 M5.0 INCH GALLATIN MT MESONET
MADISON PLATEAU SNOTEL HAD 5 INCHES OF SNOW IN 12 HOURS
FROM 10PM TO 10AM. ELEVATION 7750 FT.
1204 PM SNOW 3 NNE WEST YELLOWSTONE 44.70N 111.08W
03/16/2011 M8.0 INCH GALLATIN MT MESONET
BLACK BEAR SNOTEL HAD 8 INCHES OF SNOW IN 12 HOURS FROM
4PM TO 4AM. ELEVATION 8170 FEET.
1209 PM SNOW 22 S BIG SKY 44.95N 111.36W
03/16/2011 M6.0 INCH GALLATIN MT MESONET
BEAVER CREEK SNOTEL HAD 6 INCHES OF SNOW IN 12 HOURS
FROM 4PM TO 4AM. ELEVATION 7850 FT.
1211 PM SNOW 21 S BIG SKY 44.96N 111.29W
03/16/2011 M7.0 INCH GALLATIN MT MESONET
CARROT BASIN SNOTEL HAD 7 INCHES OF SNOW IN 12 HOURS
FROM 4PM TO 4AM. ELEVATION 9000 FT.
&&
GUSTAFSON1 high wind. Local standard time, as filed.
Sustained wind speeds of 42 mph were reported for more than an hour at the Cut Bank ASOS 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, March 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: 286120.