Strong southwest flow and favorable jet dynamics brought high wind to the Rattlesnake Range and to Casper in southern Natrona County. Gusts to 75 mph were recorded at an automated sensor in the Rattlesnake Range and a gust of 79 mph was recorded at a private sensor along Wyoming Boulevard in southwest Casper.
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The episode as NWS RIW wrote it up.
Strong southwest flow and favorable jet dynamics brought high wind to the Rattlesnake Range and to Casper in southern Natrona County. Gusts to 75 mph were recorded at an automated sensor in the Rattlesnake Range and a gust of 79 mph was recorded at a private sensor along Wyoming Boulevard in southwest Casper.
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 Riverton, WY wrote its last area forecast discussion before the first event at Nov 11, 9:31 PM MST, 9 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE RIVERTON WY 931 PM MST FRI NOV 11 2011 .UPDATE... A WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW HAS BEEN ISSUED FOR THE EXTREME NORTHWESTERN ZONES...INCLUDING JACKSON HOLE...TETON NATIONAL PARK...AND YELLOWSTONE NATIONAL PARK. A QUICK MOVING SYSTEM WITH DECENT DYNAMICS WILL SUPPORT A SHORT BUT HEAVY BURST OF SNOWFALL ACROSS THE WESTERN MOUNTAINS...THERE WILL ALSO BE STRONG WINDS AHEAD OF AND FOLLOWING THE PASSAGE OF THE TROUGH AND THE COLD FRONT ASSOCIATED WITH THIS SYSTEM. THESE WINDS WILL INCREASE THE IMPACT OF THE FALLING SNOW TO MAKE TRAVEL HAZARDOUS ACROSS THE WEST TODAY. STRONG SUBSIDENCE BEHIND THE TROUGH WILL KEEP WINDS AT THE SURFACE AFTER THE FRONT HAS PASSED...KEEPING THE CHANCE FOR REDUCED VISIBILITY IN BLOWING AND DRIFTING SNOW WELL AFTER THE SNOW HAS STOPPED ACCUMULATING. .PREV DISCUSSION... /ISSUED 237 PM MST FRI NOV 11 2011/ .SHORT TERM...TONIGHT THROUGH MONDAY PACIFIC MOISTURE WILL INCREASE ACROSS THE WEST IN WESTERLY FLOW AHEAD OF A PACIFIC TROUGH MOVING INTO THE PACIFIC NORTHWEST. SNOW WILL DEVELOP OVER THE WESTERN MOUNTAINS AFTER MIDNIGHT AS HIGH WINDS DEVELOP ALONG THE EAST SLOPES OF THE ABSAROKA MOUNTAINS AND ACROSS THE WIND CORRIDOR IN NORTHEAST SWEETWATER... SOUTHERN FREMONT AND NATRONA COUNTIES. SNOWFALL IN THE WEST WILL PICK UP THROUGH THE DAY SATURDAY LOWERING INTO THE VALLEYS AS THE DOWNSLOPE WINDS CONTINUE. WARMING WILL OCCUR WITH THE DOWNSLOPE WINDS. THE PACIFIC TROUGH AND SURFACE COLD FRONT WILL PASS THROUGH DURING THE AFTERNOON AND EARLY EVENING...BRINGING AN END TO THE HIGH WIND POTENTIAL...ALTHOUGH STRONG NORTHWEST WINDS ARE EXPECTED. FROM LATE TONIGHT THROUGH SATURDAY AFTERNOON SNOWFALL UP TO 6 INCHES IS EXPECTED IN THE WESTERN MOUNTAINS WITH UP TO 3 INCHES IN THE VALLEYS. THE MOISTURE IN THE WEST WILL DECREASE AS COLDER AIR MOVES IN WITH SNOWFALL RATES BECOMING LIGHT. SNOWFALL IN THE MOUNTAINS WILL CONTINUE...JUST NOT AS HEAVY. THE ZONAL WEST FLOW WILL CONTINUE SATURDAY NIGHT AND SUNDAY WITH LIGHT SNOWFALL IN THE WEST AND WINDY CONDITIONS ALONG AND EST OF THE CONTINENTAL DIVIDE. TEMPERATURES WILL COOL WITH COLDER AIR ALOFT...BUT THE DOWNSLOPE WARMING WILL MODERATE THE AMOUNT OF COOLING. THE FLOW WILL DRY OUT SOME SUNDAY AND SUNDAY NIGHT WITH SOME LOW LEVEL MOISTURE IN THE FLOW KEEPING SOME VERY LIGHT SNOW OVER THE MOUNTAINS. THIS WILL CONTINUE INTO MONDAY. .LONG TERM...MONDAY NIGHT THROUGH FRIDAY MODELS CONTINUE TO INDICATE A SERIES OF DISTURBANCES PUSHING THROUGH THE FORECAST AREA THROUGH THE FORECAST PERIOD. THESE DISTURBANCES WILL LEAVE SNOWFALL ACROSS THE WESTERN AND NORTHERN PORTIONS OF THE FORECAST AREA THROUGH FRIDAY...ESPECIALLY ACROSS THE NORTHWESTERN MOUNTAINS. LIGHT...ACCUMULATING SNOWFALL IS ANTICIPATED IN ASSOCIATION WITH THESE FEATURES. BECAUSE SOME DISTURBANCES ARE MAINLY ANTICIPATED TO IMPACT THE NORTHERN PORTION OF THE CWA...TEMPERATURES ON THESE SELECT DAYS WILL HAVE PERIODS OF WARMING ACROSS SOUTHERN AND EASTERN WYOMING. HOWEVER...THESE WARMER TEMPERATURES WILL BE SHORT LIVED AS SUBSEQUENT DISTURBANCES WILL BRING IN COOLER AIR OVER MOST OF THE FORECAST AREA. ASIDE FROM SNOWFALL AND TEMPERATURE VARIANCES...THE OTHER CHALLENGE IN THE FORECAST PERIOD IS THE ONGOING ANALYSIS OF INCREASED WIND. THE CONTINUED DISTURBANCES MAY BRING TIGHTER PRESSURE GRADIENTS AND FAVORED SOUTHWEST FLOW OVER THE AREA. THIS MAY RESULT IN STRONGER WIND ACROSS THE WIND CORRIDOR AND THE EASTERN SLOPES OF THE ABSAROKA AND WIND RIVER MOUNTAINS. MODELS REMAIN IN SIMILAR AGREEMENT TO THE PAST FEW DAYS. THE ECMWF REMAINS THE MORE AGGRESSIVE OF THE EXTENDED MODELS...AS IT CONTINUES TO INDICATE MORE OF A PRESENCE OF MOISTURE TO AREAS EAST OF THE DIVIDE DURING THE LATER PORTIONS OF THE FORECAST. THE GFS HAS BEGUN TO DEMONSTRATE SOME INCREASED SNOWFALL COVERAGE BY INTRODUCING THE POTENTIAL FOR SOME SHOWER ACTIVITY ACROSS SOUTHERN WYOMING. GOING FORECAST PACKAGE RETAINS A SLIGHT DRY BIAS TO ALLOW MODELS TO GET INTO BETTER ALIGNMENT. .AVIATION.../00Z ISSUANCE/ VFR CONDITIONS WILL PERSIST ACROSS THE FORECAST AREA THROUGH 06Z THIS EVENING. AFTER 06Z A STRONG SHORTWAVE WILL BEGIN TO PUSH THROUGH THE AREA. THIS SHORTWAVE WILL QUICKLY BRING SNOW TO THE WESTERN MOUNTAINS...WITH SNOWFALL MOVING INTO THE WESTERN VALLEYS BETWEEN 10Z AND 12Z SATURDAY. SNOWFALL WILL THEN SPREAD TO INCLUDE KPNA AND KBPI AFTER 14Z SATURDAY. AS THE SYSTEM PROGRESSES EASTWARD...SNOWFALL WILL BEGIN TO SPREAD TO AREAS EAST OF THE CONTINENTAL DIVIDE AFTER 18Z SATURDAY. THROUGH THE FORECAST PERIOD...MOUNTAINS WILL BE OBSCURED IN LOW CLOUDS AND SNOWFALL... AND MOUNTAIN PASSES MAY CONTAIN INCREASED TURBULENCE AS THE SHORTWAVE PROGRESSES. STRONG WIND IS EXPECTED ACROSS MUCH OF THE WIND CORRIDOR BETWEEN KRKS AND KCPR...AND ALONG THE EASTERN SLOPES OF THE WIND RIVER AND ABSAROKA MOUNTAINS THROUGH MUCH OF THE FORECAST PERIOD...WITH GUSTS TO 35 KTS POSSIBLE. OTHER AREAS WILL SEE INCREASED WIND AFTER 19Z SATURDAY...WITH A WIDESPREAD GUSTY DAY EXPECTED. .FIRE WEATHER... MOISTURE WILL INCREASE IN THE WEST WITH STRONG WINDS ALONG AND EAST OF THE CONTINENTAL DIVIDE. SNOW WILL DEVELOP LATER TONIGHT OVER THE WESTERN MOUNTAINS INCREASING THROUGH SATURDAY AND LOWERING INTO THE VALLEYS. THE STRONG DOWNSLOPE WINDS WILL PRODUCE WARMING EAST OF THE CONTINENTAL DIVIDE. && .RIW WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL 4 PM MST SATURDAY WYZ003-019-020. WINTER WEATHER ADVISORY FROM 5 AM TO 2 PM MST SATURDAY WYZ001-012-013. && SHORT TERM...C.BAKER LONG TERM...BRANHAM AVIATION...BRANHAM FIRE WEATHER...C.BAKER
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE RIVERTON WY 936 PM MST FRI NOV 11 2011 WYZ001>020-022>030-121400- ABSAROKA MOUNTAINS-BIGHORN MOUNTAINS SOUTHEAST- BIGHORN MOUNTAINS WEST-CASPER MOUNTAIN-CODY FOOTHILLS- EAST SWEETWATER COUNTY-FLAMING GORGE- GREEN MOUNTAINS AND RATTLESNAKE RANGE-JACKSON HOLE-LANDER FOOTHILLS- NATRONA COUNTY LOWER ELEVATIONS-NORTH BIG HORN BASIN- NORTHEAST JOHNSON COUNTY-OWL CREEK AND BRIDGER MOUNTAINS- ROCK SPRINGS AND GREEN RIVER-SALT RIVER AND WYOMING RANGES- SOUTH LINCOLN COUNTY-SOUTHEAST BIG HORN BASIN- SOUTHEAST JOHNSON COUNTY-SOUTHWEST BIG HORN BASIN-STAR VALLEY- TETON AND GROS VENTRE MOUNTAINS-UPPER GREEN RIVER BASIN- UPPER GREEN RIVER BASIN FOOTHILLS-UPPER WIND RIVER BASIN- WIND RIVER BASIN-WIND RIVER MOUNTAINS EAST-WIND RIVER MOUNTAINS WEST- YELLOWSTONE NATIONAL PARK- 936 PM MST FRI NOV 11 2011 ...HIGH WIND WARNINGS FOR THE LOWER ELEVATIONS OF NATRONA COUNTY... THE GREEN MOUNTAINS AND RATTLESNAKE RANGE...AND THE CODY FOOTHILLS FROM MIDNIGHT THROUGH SATURDAY AFTERNOON... ...A WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW HAS BEEN ISSUED FOR JACKSON HOLE...YELLOWSTONE NATIONAL PARK AND TETON NANTIONAL PARK FROM 5AM SATURDAY MORNING THROUGH 2PM SATURDAY AFTERNOON... THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL WYOMING. .DAY ONE...REST OF TONIGHT SOUTHWESTERLY WIND WILL GUST UP TO 60 MPH BETWEEN JEFFREY CITY AND CASPER TONIGHT. THE ABSAROKAS...WIND RIVER RANGE...THE BIGHORNS AND THE CODY FOOTHILLS. EXPECT STRONG CROSS WINDS ALONG WY120...FROM BEAVER RIM TO MUDDY GAP...AND IN THE CASPER AREA...THESE WINDS WILL CAUSE DIFFICULT TRAVEL CONDITIONS FOR HIGH PROFILE VEHICLES AND LIGHT TRAILERS. SNOW WILL BEGIN TO FALL ACROSS THE WEST TOWARD MORNING. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY SATURDAY AND SATURDAY NIGHT...SNOW AND LOW VISIBILITY IN BLOWING SNOW LIKELY IN THE WESTERN MOUNTAINS...MAKING TRAVEL AND OUTDOOR ACTIVITIES HAZARDOUS. STRONG WIND POSSIBLE ALONG EAST SLOPES OF WIND RIVER AND ABSAROKA MOUNTAINS...AS WELL AS PORTIONS SOUTH CENTRAL WYOMING. SUNDAY THROUGH WEDNESDAY...INTERMITTENT ACCUMULATING SNOW WITH AREAS OF BLOWING SNOW IN THE NORTHERN AND WESTERN MOUNTAINS. .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT STRONG WINDS IN EXCESS OF 40 MPH AND ANY WIND DAMAGE TONIGHT. SPOTTERS ARE ENCOURAGED TO REPORT SNOWFALL AMOUNTS ON SATURDAY AS WELL. TEAM RIVERTON
The national radar mosaic for the moment the first event began.
2 high wind. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2011Every state in 2011This day in weather historyWarnings in Wyoming, November 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: 353986, 353987.