A strong pressure gradient, in combination with a stable atmosphere, created strong winds over parts of Interstate 80. This episode continued into December 2010.
Every event with a place to put it; 8 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 CYS wrote it up.
A strong pressure gradient, in combination with a stable atmosphere, created strong winds over parts of Interstate 80. This episode continued into December 2010.
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 29, 9:22 PM MST, 5 hours 23 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHEYENNE WY 922 PM MST MON NOV 29 2010 .UPDATE... NORTHWEST WINDS HAVE DECREASED OVER THE PAST HOUR OR TWO...SO WENT AHEAD AND CANCELLED THE WIND ADVISORY FOR THE PANHANDLE. NORTHWEST WINDS WILL CONTINUE TO DECREASE THROUGH THE REMAINDER OF THE OVERNIGHT HOURS. && .PREV DISCUSSION... /ISSUED 615 PM MST MON NOV 29 2010/ UPDATE... SATELLITE PIX AND AREA WEBCAMS INDICATE THE SNOW OVER THE SNOWY RANGE AND SIERRA MADRES CONTINUING TO WANE. SO...ALLOWED THE WINTER WEATHER ADVISORY TO EXPIRE ON SCHEDULE AT 6 PM. PREV DISCUSSION... /ISSUED 321 PM MST MON NOV 29 2010/ UPDATE... ALLOWED WINTER WEATHER ADVISORY FOR THE WESTERN AND NORTHERN ZONES TO EXPIRE AT 3 PM. SNOW HAS ENDED ACROSS THIS AREA AND WINDS HAVE STARTED TO DECREASE. A WIND ADVISORY WILL REMAIN IN EFFECT UNTIL 11 PM FOR THE NEB PANHANDLE...AND A WINTER WEATHER ADVISORY WILL CONTINUE UNTIL 6 PM FOR THE SOUTH CENTRAL MOUNTAINS. PREV DISCUSSION... /ISSUED 149 PM MST MON NOV 29 2010/ SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT IR SATELLITE CONTINUES TO SHOW A DECREASING TREND IN ENHANCEMENT OVER THE AREA AS CLOUD TOPS ARE SLOWLY WARMING. THIS INDICATES THAT SNOW SHOULD CONTINUE TO TAPER OFF THROUGH THE REST OF THIS AFTERNOON AND INTO THIS EVENING. HAVE LET THE WINTER WEATHER ADVISORY FOR THE WESTERN AND NORTHERN ZONES EXPIRE. HOWEVER...WILL KEEP THE WINTER WEATHER ADVISORY FOR THE SNOWY AND SIERRA MADRES WHERE SNOW AND BLOWING SNOW WILL LINGER INTO THIS EVENING. WILL ALSO KEEP THE WIND ADVISORY FOR THE NEB PANHANDLE IN EFFECT UNTIL MIDNIGHT AS WINDS ARE STILL AROUND 30 MPH GUSTING TO AROUND 45 MPH. THE GRADIENT WILL BEGIN TO RELAX AFTER SUNSET AND THE ADVISORY MAY BE ABLE TO BE CANCELLED BY MID EVENING. NNW FLOW WILL OCCUR ALOFT TONIGHT AS A DEEP UPPER TROUGH MOVES EAST OF THE PLAINS AND AN UPPER RIDGE MOVES OVER THE WESTERN U.S. A WEAK SHORT WAVE IN THE FLOW WILL MOVE OVER THE SOUTHERN MOUNTAINS...RESULTING IN SOME LINGERING SNOW SHOWERS OVERNIGHT. THE REST OF THE AREA WILL SEE DECREASING CLOUDS AND WINDS OVERNIGHT. NW FLOW WILL OCCUR ALOFT TUES BETWEEN THE DEEP UPPER TROUGH TO THE EAST AND AN UPPER RIDGE OVER THE WESTERN U.S. TEMPERATURES WILL REBOUND A BIT ON TUES WITH WEST TO NORTHWEST DOWNSLOPE WINDS AT THE SURFACE. WINDY CONDITIONS WILL OCCUR ONCE AGAIN ON TUES...BUT THEY SHOULD NOT BE AS STRONG AS TODAY AT THE LOWER ELEVATION OR THE NEB PANHANDLE. THERE IS SOME INDICATION IN THE 700 MB GRADIENT THAT A HIGH WIND WATCH MAY BE NEEDED FOR THE MOUNTAINS FOR TUES NIGHT. NW FLOW WILL CONT ALOFT TUES NIGHT THROUGH WED NIGHT AS THE UPPER RIDGE REMAINS TO THE WEST OF THE FORECAST AREA. TEMPERATURES WILL BE EVEN WARMER ON WED AS THE SURFACE TO 500MB THICKNESS VALUES INCREASE OVER THE AREA. A WEAK DISTURBANCE WILL MOVE OVER THE WESTERN PORTION OF THE CWA ON WED WHICH WILL RESULT IN A CHANCE OF SNOW...MAINLY FOR THE SOUTHERN MOUNTAINS. SNOWFALL AMOUNTS WILL BE AROUND AN INCH OR TWO IN THE SNOWY AND SIERRA MADRE RANGES. LONG TERM...THURSDAY THROUGH MONDAY SOME DISCREPANCIES SEEN IN MEDIUM RANGE MODELS THAT COULD HAVE BIG IMPACTS ON WEATHER THROUGH THE WEEKEND. BOTH THE GFS AND ECMWF START THURSDAY OFF IN AGREEMENT WITH AN UPPER RIDGE OF HIGH PRESSURE BUILDING INTO THE AREA. THIS WILL RESULT IN DRY WEATHER AND WARMER TEMPERATURES THURSDAY WITH HIGHS IN THE UPPER 40S EAST OF THE LARAMIE RANGE...MID TO UPPER 30S WEST. 700MB TEMPERATURES THURSDAY NIGHT CLIMB ABOVE FREEZING ON BOTH MODELS...WITH THE GFS ABOUT 4 DEGREES C WARMER THAN THE ECMWF. REGARDLESS...LOW FRIDAY MORNING LOOK TO BE IN THE UPPER 20S TO LOW 30S CWA-WIDE. CHANGES BEGIN FRIDAY AS THE ECMWF DRIVES A SHORTWAVE THROUGH FROM THE NORTHWEST. GFS HOLDS ONTO THE UPPER RIDGE INTO SATURDAY MORNING. WENT WITH THE ECMWF SOLUTION...INTRODUCING CHANCE POPS INTO CARBON COUNTY FRIDAY AFTERNOON AND SLOWLY SPREADING POPS EASTWARD OVERNIGHT INTO SATURDAY. GFS FINALLY DROPS A DRY COLD FRONT THROUGH SOUTHERN WYOMING SUNDAY MORNING WITH NO PRECIP FORECAST. WILL NEED TO MONITOR THIS FOR A FEW MORE MODEL RUNS TO SEE IF BETTER AGREEMENT MATERIALIZES LATER THIS WEEK. && .AVIATION...06Z TAF ISSUANCE... VFR CONDITIONS WILL PREVAIL AT AREA TERMINALS THROUGH THE PERIOD. THERE WILL BE ISOLATED SNOW SHOWERS THAT PERSIST ACROSS THE SOUTHEAST WYOMING MOUNTAINS OVERNIGHT...SO MOUNTAIN OBSCURATIONS ARE EXPECTED THERE. OTHERWISE...PANHANDLE LOCATIONS WILL SEE NORTHWEST WINDS DECREASE THROUGH THE REST OF THE NIGHT AND INCREASE ONCE AGAIN ON TUESDAY. MEANWHILE...NORTHWEST WINDS WILL BECOME MORE WESTERLY AT WYOMING TERMINALS AND SHOULD STAY BREEZY THROUGHOUT THE PERIOD. && .FIRE WEATHER...NO FIRE WEATHER CONCERNS DUE TO SNOWFALL AND LOW FIRE DANGER. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && AVIATION/UPDATES...HAHN SHORT TERM/FIRE WEATHER...KMD LONG TERM...CLAYCOMB
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHEYENNE WY 947 PM MST MON NOV 29 2010 WYZ101>119-010500- 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- 947 PM MST MON NOV 29 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST CENTRAL WYOMING... SOUTH CENTRAL WYOMING AND SOUTHEAST WYOMING. .DAY ONE...TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY WEST WINDS WILL INCREASE TO 25 TO 35 MPH WITH GUSTS UP TO 50 MPH IN AND AROUND THE SOUTHEAST WYOMING MOUNTAINS ON TUESDAY AND TUESDAY NIGHT. .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 NEZ002-003-019>021-054-055-095-096-010500- DAWES-BOX BUTTE-SCOTTS BLUFF-BANNER-MORRILL-KIMBALL-CHEYENNE- NORTH SIOUX-SOUTH SIOUX- 947 PM MST MON NOV 29 2010 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...TUESDAY THROUGH SUNDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .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.
8 high wind. Local standard time, as filed.
The Union Pacific Railroad sensor at Buford reported sustained winds at or above 40 mph during this time frame. A peak gust of 60 mph occurred at 1400LST.
The sensor at Arlington reported sustained winds at or above 40 mph during this time frame. A peak gust of 65 mph occurred at 1111LST.
The Union Pacific Railroad sensor at Lynch reported sustained winds at or above 40 mph from 415LST to 515LST, and from 1545LST to 1755LST. A peak gust of 58 mph occurred at 445LST.
The Union Pacific Railroad sensor at Emkay reported sustained winds at or above 40 mph during this time frame. A peak gust of 71 mph occurred at 755LST and 1145LST.
The sensor at Vedauwoo measured sustained winds at or above 40 mph from 912LST to 1627LST, and from 2032LST to 2357LST. A peak gust of 58 mph occurred at 2332LST and 2337LST.
The sensor at Wyo Hill on Interstate 25 reported sustained winds at or above 40 mph during this time frame.
The Union Pacific Railroad sensor at Pumpkin Vine reported wind gusts of 58 mph at 1456LST and 1501LST.
The sensor at Bordeaux on Interstate 25 reported sustained winds at or above 40 mph during this time frame. A peak gust of 61 mph occurred at 2315LST and 2320LST.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2010Every state in 2010This day in weather historyWarnings in Wyoming, November 2010
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: 264607, 264463, 264609, 264610, 264464, 264611, 264608, 264612.