A strong upper level disturbance and cold front moved across southeast Wyoming. Sustained west to southwest winds of 35 to 45 mph with gusts to near 70 mph occurred near the Arlington and Elk Mountain areas.
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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 CYS wrote it up.
A strong upper level disturbance and cold front moved across southeast Wyoming. Sustained west to southwest winds of 35 to 45 mph with gusts to near 70 mph occurred near the Arlington and Elk Mountain areas.
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 Cheyenne, WY wrote its last area forecast discussion before the first event at Nov 30, 9:21 PM MST, 15 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHEYENNE WY 921 PM MST FRI NOV 30 2012 .UPDATE... MAIN FOCUS THIS EVENING IS WIND SPEEDS OVER THE WIND PRONE AREAS. AT THIS TIME WINDS REMAIN RELATIVELY SUBDUED. WINDS CURRENTLY GUSTING BELOW 40 MPH IN THE ARLINGTON AREA AND BELOW 20 MPH AT BORDEAUX. MODELS CONTINUE TO INCREASE WINDS ALOFT OVER THE NEXT SEVERAL HOURS BUT NEED TO START SEEING AN INCREASE IN WINDS SOON IF GOING TO HIT HIGH WIND WARNING CRITERIA. NAM AND GFS NOT SHOWING REALLY SHOWING A STABLE LAYER CONDUCIVE OF DIRECTING SURFACE WINDS ALOFT TO THE SURFACE. WOULD LIKE TO SEE A STRONGER STABLE LAYER FOR HIGHER WIND SPEEDS. NO PLANS ON DROPPING HIGH WIND WARNING AT THIS TIME BUT IF WINDS DON'T PICK UP OVER THE NEXT SEVERAL HOURS...IT MAY THEN BE SOMETHING FOR THE NIGHT SHIFT TO CONSIDER. && .PREV DISCUSSION... /ISSUED 400 PM MST FRI NOV 30 2012/ SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT...THE MAIN WEATHER IMPACT LATE TODAY AND INTO THE WEEKEND WILL BE STRONG WINDS. WEST TO SOUTHWEST FLOW ALOFT WILL CONTINUE OVER THE AREA INTO SATURDAY NIGHT WITH WARMER THAN NORMAL TEMPERATURES IN THE 50S TO MID 60S LIKELY. MODEL SHOW A WEAK DISTURBANCE ALOFT QUICKLY PUSHING THROUGH THE FORECAST AREA TONIGHT. A BRIEF PERIOD OF LIGHT SNOWFALL IS EXPECTED IN THE MOUNTAINS WHERE 2 TO 4 INCHES OF SNOW ACCUMULATION IS POSSIBLE. OTHERWISE...DRY CONDITIONS ARE EXPECTED FURTHER EAST DUE TO DRY DOWNSLOPE WINDS. MODELS INDICATE A STRENGTHENING SURFACE AND 700MB PRESSURE GRADIENT THIS EVENING WITH 700 MB WINDS UP TO 60 KNOTS NEAR THE COLORADO BORDER ALONG I80. CONTINUED THE HIGH WIND WARNING FOR THE WIND PRONE LOCATIONS. THERE IS SOME CONCERN THAT HIGH WINDS MAY BE OBSERVED OVER THE FOOTHILLS OF THE SOUTHERN LARAMIE RANGE...AFFECTING I80 AND I25 NEAR CHEYENNE. PORTIONS OF NORTHERN CARBON COUNTY AND ALBANY COUNTY MAY SEE GUSTS AROUND 55 MPH AS WELL...BUT THAT WILL LIKELY OCCUR AFTER SUNRISE SATURDAY MORNING. STRONG WINDS WILL THEN LOWER OVER THE WIND PRONE LOCATIONS OVER SOUTHEAST WYOMING SATURDAY AFTERNOON...ALTHOUGH WINDY CONDITIONS WILL DEVELOP ACROSS MOST OF THE FORECAST AREA DUE TO LLVL MIXING. WARMER TEMPERATURES ARE EXPECTED ON SUNDAY WITH HIGHS NEAR 70 ACROSS PORTIONS OF THE NEBRASKA PANHANDLE AS 700MB TEMPERATURES WARM OVER 5C AHEAD OF THE NEXT SURFACE COLD FRONT AND ASSOCIATED TROUGH. HOWEVER...EVEN STRONGER WINDS COMPARED TO TONIGHT ARE POSSIBLE SUNDAY AND SUNDAY NIGHT AS THE COLD FRONT APPROACHES. 700MB WINDS INCREASE TO 70 KNOTS SUNDAY EVENING AS THE COLD FRONT MOVES ACROSS THE FORECAST AREA. WINTER WEATHER HEADLINES LOOK POSSIBLE FOR THE MOUNTAINS SUNDAY NIGHT WITH A GREATER POTENTIAL OF HEAVY SNOW...WITH ANOTHER ROUND OF HIGH WIND WATCHES/WARNINGS LIKELY SUNDAY AFTERNOON. LONG TERM...MONDAY THROUGH FRIDAY... PROGRESSIVE ZONAL PATTERN TO REMAIN IN PLACE THROUGH THE MIDDLE OF NEXT WEEK WITH MOST MEDIUM RANGE GUIDANCE INDICATING A COOL DOWN BEHIND A COLD FRONTAL PASSAGE FOR THURSDAY AND FRIDAY. THE MAIN STORM TRACK WILL BE CONFINED TO THE NORTH FOR MONDAY THRU WEDNESDAY STEERING A SERIES OF SHORTWAVES GENERALLY NORTH OF THE CWFA. WILL BE DEALING WITH THE REMNANTS OF WHAT WILL BE THE SECOND BOUT WITH STRONG WINDS LATE SUNDAY NIGHT. ALTHOUGH THE LLVL GRADIENT WILL CONTINUE TO BE TIGHT EARLY MONDAY...MODELS SHOW IT RELAXING SOME THROUGH THE DAY. SO...EXPECT CONDITIONS TO REMAIN BREEZY BUT TEMPERATURES STILL FAIRLY MILD ON MONDAY. LEE SIDE SURFACE PRESSURES WILL FALL AGAIN ON TUESDAY...SETTING UP POTENTIALLY ANOTHER MARGINAL HIGH WIND EVENT TUESDAY NIGHT/EARLY WEDNESDAY AS H7 PROGS CLIMB AGAIN TO NEAR 50 KNOTS. TEMPERATURES WILL REMAIN MILD AS H7 TEMPERATURES CLIMB FROM -4C ON MONDAY...TO NEAR 2C FOR TUESDAY AND WEDNESDAY. THIS WILL WARM HIGH TEMPERATURES THAT WILL BE MAINLY IN THE 40S ON MONDAY BACK INTO THE 50S AND EVEN SOME LOW 60S OVR THE PANHANDLE BY WEDNESDAY. MODELS CONSISTENTLY POINT TO A COLD FROPA EARLY THURSDAY...WHICH WILL USHER IN COOLER TEMPERATURES FOR FRIDAY. TEMPERATURES WILL BE TRICKY ON THURSDAY BEING SOLELY DEPENDENT UPON FROPA TIMING. WOULD NOT BE SURPRISED TO SEE HIGH TEMPERATURES BEING REACHED EARLY IN THE DAY AND COOLING THEREAFTER. THIS COLD FRONT WILL PROVIDE THE NEXT CHANCE FOR WIDESPREAD PRECIPITATION ON THURSDAY. ALTHOUGH ITS STILL A LONG WAYS OUT...GIVEN THE SYSTEMS SPEED ANY ACCUMULATIONS LOOKS TO BE ON THE LIGHT SIDE. THE AIR MASS WILL BE DRIER FOR FRIDAY...WITH TEMPERATURES THAT WILL ONLY REACH INTO THE 30S FOR MOST PLACES. AVIATION...00Z ISSUANCE... VFR CONDITIONS WILL PREVAIL AT MOST TERMINALS THIS PERIOD WITH JUST SOME MID/HIGH-LEVEL CLOUDS PASSING THRU. THE EXCEPTION WILL BE AT KRWL WHERE MVFR/IFR CONDITIONS CAN BE EXPECTED 08-14Z IN -SN. OTHERWISE A BREEZY TO LOCALLY WINDY PATTERN TAKING SHAPE AT WYOMING AIRFIELDS. GUSTS OF 25 TO 40 KNOTS CAN BE EXPECTED AT WYOMING TERMINALS TONIGHT AND TOMORROW. MEANWHILE WINDS IN THE WESTERN NEBRASKA PANHANDLE WILL WAIT TO INCREASE UNTIL AFTER 17Z. FIRE WEATHER...FIRE WEATHER CONCERNS WILL BE MINIMAL THROUGH THE WEEKEND AND INTO NEXT WEEK. BREEZY OR WINDY CONDITIONS WILL CONTINUE THIS WEEKEND AS A SERIES OF LOW PRESSURE SYSTEMS TRACK NORTH OF THE AREA ACROSS MONTANA AND SOUTHERN CANADA. MOUNTAIN SNOWFALL IS EXPECTED SUNDAY NIGHT AS A COLD FRONT MOVES SOUTHEAST...OTHERWISE DRY WEATHER IS EXPECTED ACROSS THE HIGH PLAINS. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...HIGH WIND WARNING UNTIL 11 AM SATURDAY FOR WYZ106-WYZ110-WYZ116. NE...NONE. && UPDATE...LIEBL
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHEYENNE WY 854 PM MST FRI NOV 30 2012 WYZ101>119-010945- CONVERSE COUNTY LOWER ELEVATIONS-NIOBRARA COUNTY- NORTH LARAMIE RANGE-FERRIS/SEMINOE/SHIRLEY MOUNTAINS- SHIRLEY BASIN-CENTRAL LARAMIE RANGE AND SOUTHWEST PLATTE COUNTY- EAST PLATTE COUNTY-GOSHEN COUNTY-CENTRAL CARBON COUNTY- NORTH SNOWY RANGE FOOTHILLS-SOUTHWEST CARBON COUNTY- SIERRA MADRE RANGE-UPPER NORTH PLATTE RIVER BASIN-SNOWY RANGE- LARAMIE VALLEY-SOUTH LARAMIE RANGE-SOUTH LARAMIE RANGE FOOTHILLS- CENTRAL LARAMIE COUNTY-EAST LARAMIE COUNTY- 854 PM MST FRI NOV 30 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST CENTRAL WYOMING... SOUTH CENTRAL WYOMING AND SOUTHEAST WYOMING. .DAY ONE...TONIGHT HIGH WIND WARNINGS REMAIN IN PLACE TONIGHT THROUGH SATURDAY MORNING FOR WIND PRONE AREAS OF ARLINGTON...BORDEAUX AND VEDAUWOO IN SOUTHEAST WYOMING. WIND GUSTS AROUND 60 MPH ARE EXPECTED AREAS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY A STRONGER AND MORE WIDESPREAD HIGH WIND EVENT TO TAKE SHAPE SUNDAY EVENING INTO MONDAY AS LOW PRESSURE TRACKS ACROSS MONTANA. WIDESPREAD WIND GUSTS OF 55 TO 65 MPH LOOK LIKELY ACROSS MUCH OF SOUTHEAST WYOMING SUNDAY EVENING INTO MONDAY...WITH 65 TO 75 MPH GUSTS FOR WIND PRONE AREAS LIKE ARLINGTON...BORDEAUX AND VEDAUWOO. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY AND TONIGHT. && THIS PRODUCT...ALONG WITH OTHER WEATHER...HYDROLOGIC...AND CLIMATE INFORMATION IS AVAILABLE ON THE WEB AT... HTTP://WEATHER.GOV/CHEYENNE NEZ002-003-019>021-054-055-095-096-010945- DAWES-BOX BUTTE-SCOTTS BLUFF-BANNER-MORRILL-KIMBALL-CHEYENNE- NORTH SIOUX-SOUTH SIOUX- 854 PM MST FRI NOV 30 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE WESTERN NEBRASKA PANHANDLE. .DAY ONE...TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY WEST TO NORTHWEST WINDS OF 30 TO 40 MPH SUSTAINED WITH GUSTS EXCEEDING 50 MPH ARE POSSIBLE SUNDAY EVENING INTO MONDAY AS A STRONG LOW PRESSURE SYSTEM TRACKS THROUGH MONTANA. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TONIGHT. && THIS PRODUCT...ALONG WITH OTHER WEATHER...HYDROLOGIC...AND CLIMATE INFORMATION IS AVAILABLE ON THE WEB AT... HTTP://WEATHER.GOV/CHEYENNE
The national radar mosaic for the moment the first event began.
2 high wind. Local standard time, as filed.
The WYDOT site at Interstate 80 mile marker 249.1 measured sustained winds of 40 mph or higher.
The WYDOT site at Halleck Ridge measured wind gusts of 58 mph or higher, with a peak gust of 71 mph at 30/2316 MST.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2012Every state in 2012This day in weather historyWarnings in Wyoming, November 2012
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: 415510, 415512.