West winds increased during the overnight hours around Elk Mountain in Carbon County.
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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.
West winds increased during the overnight hours around Elk Mountain in Carbon County.
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 23, 8:44 PM MST, 4 hours 32 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHEYENNE WY 844 PM MST MON NOV 23 2009 .UPDATE... A DRYING AND STABILIZING AIR MASS HAS DISSIPATED ANY HINT OF WRAP-AROUND MOISTURE ACROSS SE ZONES THIS EVENING. SATELLITE PIX DEPICT ONLY A FEW CLOUD FRAGMENTS REMAINING ACROSS SOUTHEAST WYOMING AND THE WESTERNMOST ROW OF COUNTIES IN NEBRASKA. SO...HAVE REDUCED CLOUD-COVER ACROSS ALL AREAS OF THE CWA OVERNIGHT. REMOVED PRECIP CHANCES ACROSS THE SOUTHEAST...BUT DID KEEP SMALL CHANCES GOING ACROSS JUST THE HIGHER PEAKS OF THE SNOWY RANGE THROUGH MIDNIGHT. OTHERWISE...CONDITIONS WILL REMAIN DRY THROUGH THE REMAINDER OF THE OVERNIGHT. HAHN && .PREV DISCUSSION... /ISSUED 152 PM MST MON NOV 23 2009/ SHORT TERM...TONIGHT THROUGH WEDNESDAY...CURRENT KCYS RADAR LOOP SHOWS ISOLD SNOW SHOWERS/FLURRIES OVER THE MOUNTAINS OF SRN WYOMING AND ALONG I25 NORTH OF CHEYENNE WITH DOUGLAS REPORTING A HALF MILE VISIBILITY AND MODERATE SNOW IN THE LAST HALF HOUR. EXPECT HIS ACTIVITY TO REMAIN ISOLATED INTO LATE THIS AFTERNOON BEFORE DISSIPATING AROUND SUNSET AS THE COLD FRONT AND INTENSIFYING SURFACE LOW OVER KANSAS CONTINUE TO PUSH EAST OF THE REGION TONIGHT. EXPECT TEMPS TO REMAIN BELOW NORMAL TONIGHT WITH CLEARING SKIES AND GOOD RADIATIONAL COOLING. WINDS WILL SLOWLY DISSIPATE BY MIDNIGHT AS THE PRESSURE GRADIENT DECREASES ACROSS THE REGION. THE UPPER LEVEL TROUGH CURRENTLY OVER THE AREA IS EXPECTED TO PUSH EAST OF THE AREA INTO THE GREAT PLAINS AND GREAT LAKES REGION BY TUESDAY RESULTING IN COOL NORTHWEST FLOW OVER SOUTHEAST WYOMING AND THE NEBRASKA PANHANDLE...WITH HIGHS IN THE UPPER 30S TO UPPER 40S EAST OF THE LARAMIE RANGE...AND UPPER 20S TO MID 30S ACROSS CARBON AND ALBANY COUNTIES. MODELS IN GOOD AGREEMENT FOR WEDNESDAY...SHOWING THE NEXT COLD FRONT MOVING INTO THE HIGH PLAINS. THIS FRONT WILL BE DRIER...SINCE ITS EXPECTED TO MOVE INTO THE AREA FROM THE NORTH AND HAS VERY LITTLE MOISTURE WITH IT. HOWEVER...MODELS SHOW A STRONG 120 KT JET PUSHING ACROSS ERN WYOMING EARLY WEDNESDAY AND SOME LLVL LIFT...SO CAN NOT RULE OUT A BAND OF LIGHT SNOW OR FLURRIES ALONG THE FRONT OVER THE NRN NEBRASKA PANHANDLE AND ERN WYOMING TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING. AFTER THE FRONT PUSHES ACROSS THE AREA...EXPECT WINDS TO INCREASE FROM THE NORTH BETWEEN 25 TO 35 MPH WITH GUSTS POSSIBLY AROUND 50 MPH WEDNESDAY ALONG AND EAST OF THE LARAMIE RANGE WITH WIND ADVISORY CONDITIONS POSSIBLE OVER THE PANHANDLE. OTHERWISE...COOLER THAN NORMAL TEMPS WILL CONTINUE INTO WEDNESDAY WITH HIGHS 3 TO 7 DEGS COOLER COMPARED TO TUESDAY. LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY...DRY AND MILD CONDITIONS EXPECTED FOR THANKSGIVING DAY THROUGH FRIDAY AS AN UPPER RIDGE SHIFTS ACROSS THE REGION. SOME BREEZINESS OVER AN CLOSE TO THE MOUNTAINS AS SOME SFC TROFFING CREATES SOME DECENT PRESSURE GRADIENT BUT NO HIGH WINDS FORESEEN. OVER THE WEEKEND INTO EARLY NEXT WEEK NEXT UPPER SYSTEM SHOULD AFFECT THE AREA. MODELS DIFFER ON HANDLING OF THIS SYSTEM...MAINLY WITH HOW MUCH ENERGY GOES WHERE...WHICH WOULD AFFECT DETAILS OVER THE CWA. CURRENT EXTENDED FCST LOOKS TO BE IN DECENT SHAPE AND CANNOT SEE GOOD REASON TO ALTER AT THIS TIME. WILL MAINTAIN COOLING TREND OVER THE WEEKEND AS NEXT FRONT DUE FRIDAY NIGHT WITH SOME LIGHT PCPN POSSIBLE MAINLY OVERT THE MTNS AND FAR NORTH SECTIONS OF THE CWA. OTHERWISE NO BIG SURGES OF VERY COLD AIR SEEN HEADED THIS WAY WITH GENERALLY PROGRESSIVE PATTERN KEEPING ARCTIC AIR BOTTLED WELL NORTH. && AVIATION...CURRENT OBSERVATIONS SHOW IMPROVING CONDITIONS THIS AFTERNOON AS THE COLD FRONT...WHICH PUSHED ACROSS THE AREA YESTERDAY EVENING AND LAST NIGHT...CONTINUES TO MOVE SOUTHEAST INTO KANSAS AND CNTRL NEBRASKA. SNOW HAS DIMINISHED TO ISOLD SNOW SHOWERS...MAINLY IN THE MOUNTAINS AND ALONG I25. HOWEVER...NORTHWEST WINDS WILL REMAIN GUSTY INTO THIS EVENING WITH SUSTAINED WINDS BETWEEN 15 TO 25 KTS AND GUSTS AROUND 35 KTS...BECOMING WEST AND DIMINISHING TO 10 TO 20 KTS LATE IN THE EVENING. EXPECT BRIEF PERIODS OF IFR CONDITIONS IN MODERATE SNOW SHOWERS LATE THIS AFTERNOON...WITH ACTIVITY DISSIPATING AROUND SUNSET. && FIRE WEATHER...NO FIRE WEATHER CONCERNS THROUGH THURSDAY WITH COOL TEMPERATURES AND HIGH HUMIDITIES EXPECTED. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && SHORT TERM/AVIATION...TJT LONG TERM...RE
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHEYENNE WY 1218 PM MST MON NOV 23 2009 NEZ002-003-019>021-054-055-095-096-WYZ101>119-241230- DAWES-BOX BUTTE-SCOTTS BLUFF-BANNER-MORRILL-KIMBALL-CHEYENNE- NORTH SIOUX-SOUTH SIOUX-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- 1218 PM MST MON NOV 23 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE WESTERN NEBRASKA PANHANDLE...EAST CENTRAL WYOMING...SOUTH CENTRAL WYOMING AND SOUTHEAST WYOMING. .DAY ONE...THIS AFTERNOON AND TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .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
The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
Wyoming Department of Transportation sensor (KARL) measured sustained winds in excess of 40 mph from 116 through 621 AM with a peak gust of 62 mph at 3 AM.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2009Every state in 2009This day in weather historyWarnings in Wyoming, November 2009
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: 197544.