Favorable jet dynamics and a tight pressure gradient brought mountain wave activity to the Cody and Lander foothills. The hardest hit area was in Park County along the foothills from Cody to Clark.
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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 RIW wrote it up.
Favorable jet dynamics and a tight pressure gradient brought mountain wave activity to the Cody and Lander foothills. The hardest hit area was in Park County along the foothills from Cody to Clark. Peak gusts on the west side of Cody frequently topped 60 mph and peaked at 79 mph at 1356MST. Farther north near Clark, gusts routinely blew in excess of 70 mph with a peak wind of 95 mph recorded at 0813MST. High wind was also recorded across Johnson and Natrona counties as well as southern Fremont 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 Riverton, WY wrote its last area forecast discussion before the first event at Jan 24, 10:33 PM MST, 1 hour 7 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RIVERTON WY 1033 PM MST TUE JAN 24 2012 .SHORT TERM...TONIGHT THROUGH FRIDAY OUR QUICK HITTING STORM SYSTEM PRODUCED A QUICK 2 TO 5 INCHES OUT WEST AND ALONG THE FOOTHILLS FROM LANDER TO CASPER...CASPER MOUNTAIN LAST NIGHT INTO THIS MORNING. RAPID CLEARING FOR MOST AREAS THIS MORNING EXCEPT FOR PERSISTENT LOW CLOUDS AND AREAS OF FOG IN PARTS OF THE STAR VALLEY...ESPECIALLY SOUTH AND ALONG THE FOOTHILLS. NEXT SYSTEM IS FAST APPROACHING ALONG WITH MASSIVE 180KT MOVING ACROSS THE EASTERN PACIFIC AND ONTO THE PACNW COAST. THE MAIN CONCERN FOR TONIGHT WILL BE EXPECTED HIGH WIND EVENT ALONG THE CODY FOOTHILLS BEGINNING THIS EVENING AND CONTINUING THROUGH MUCH OF THE DAY WEDNESDAY. THIS SYSTEM IS VERY SIMILAR TO A HIGH WIND EVENT ON NOVEMBER 16TH AND 17TH WHICH PRODUCED 87 MPH WINDS IN CLARK AND 100 MPH WINDS IN THE CLARK'S FORK GAP. HOWEVER...THIS SYSTEM IS SHOWING EVEN STRONGER PARAMETERS INCLUDING A MUCH STRONGER JET...STRONGER MOUNTAIN TOP INVERSION...STRONGER THERMAL GRADIENT FOR GAP FLOW AND EVEN A STRONGER MOUNTAIN WAVE SIGNATURE ON THE LCL WRF CROSS SECTION AROUND CLARK. HAVE BEEFED UP THE WIND SPEEDS WITH THE HIGH WIND WARNING UPGRADE TO INCLUDE 80 TO 90 MPH OR MORE AROUND CLARK. SOME CONCERN THAT THIS COULD BE A MORE RARE 100-120 MPH TYPE EVENT FOR CLARK AND VICINITY. SHOULD SEE A THREE PRONGED EVENT WITH INITIAL GAP FLOW EARLY IN THE EVENING...THEN SOME AREAS OF MOUNTAIN WAVE...ESPECIALLY AROUND AND JUST SOUTH OF CLARK AND FINALLY A MORE WIDESPREAD HIGH WIND EVENT DURING THE DAY WEDNESDAY AS RIGHT FRONT QUAD OF 180KT JET MOVES INTO A FAVORABLE POSITION. OUT WEST...LIGHT SNOW WILL MOVE IN QUICKLY THIS EVENING WITH AN INCREASINGLY FAVORABLE ISENTROPIC UPGLIDE SIGNATURE. SNOW LOOKS GENERALLY LIGHT FOR TONIGHT THROUGH WEDNESDAY NIGHT WITH MORE SIGNIFICANT SNOW POSSIBLE AS A STRONGER SHORTWAVE DEVELOPS AND MOVES INTO THE AREA LATE THURSDAY INTO THURSDAY EVENING ALONG WITH VERY FAVORABLE DENDRITIC GROWTH TEMPERATURES IN THE CLOUD LAYER. COLD FRONT WILL ALSO EFFECT AREAS EAST OF THE DIVIDE THURSDAY NIGHT WITH A BRIEF PERIOD OF UPSLOPE AND LIGHT SNOW POSSIBLE... ESPECIALLY FROM LANDER TO CASPER. MUCH COLDER FRIDAY WITH -13 TO -15C AIR AT H7. UNTIL THEN...FAIRLY MILD...ESPECIALLY EAST OF THE DIVIDE THE NEXT COUPLE DAYS. NUDGED SOME TEMPERATURES UP WEDNESDAY BUT NOT QUITE BUYING INTO THOSE MID 60S THE MAV HAS FOR LANDER! COULD SEE 50S BUT FOR NOW KEPT THEM IN THE MID TO UPPER 40S. A LOT OF AREAS WILL SEE SOME WIND THE NEXT FEW DAYS...ESPECIALLY THE DUBOIS AREA AND THE WIND CORRIDOR TO INCLUDE CASPER. SHOULD RESULT IN MILDER OVERNIGHT LOWS. .LONG TERM...FRIDAY NIGHT THROUGH TUESDAY THE BEGINNING OF THE FORECAST PERIOD TO REMAIN FAIRLY BENIGN UNDER NORTHWEST FLOW. THE FORECAST THEN BECOMES A BIT CHALLENGES AS MODELS CONTAIN SIGNIFICANT VARIANCES AFTER SUNDAY MORNING. THE ECMWF APPEARS TO BE THE SLIGHTLY FAVORED SOLUTION AS IT INDICATES SOME MOISTURE ASSOCIATED WITH A WEAK SHORTWAVE MOVING INTO NORTHWESTERN WYOMING SUNDAY MORNING. THE GFS...MEANWHILE...MAINTAINS A DRY RIDGE. GOING FORECAST TRENDS TOWARDS THE ECMWF...THOUGH IT DOES NOT INDICATE SIGNIFICANT POPS FOR NOW UNTIL MODELS BEGIN TO COME INTO BETTER AGREEMENT. THAT BEING SAID...SNOWFALL POTENTIAL EXISTS ACROSS THE WESTERN MOUNTAINS THROUGH MUCH OF THE REMAINDER OF THE FORECAST PERIOD AS A SERIES OF SHORTWAVES ARE EXPECTED TO IMPACT THE FORECAST AREA. LOW PRECIPITATION PROBABILITIES REMAIN INCLUDED IN THE CURRENT FORECAST PACKAGE. TEMPERATURES WILL REMAIN A STRONG CHALLENGE UNTIL IT IS DETERMINED IF ADDITIONAL ACCUMULATING SNOWFALL WILL OCCUR...OR IF THE WEAK WAVES WILL INDEED BRING COOLER AIR ACROSS THE FORECAST AREA. ATTEMPTED TO MAKE MINOR CHANGES TO THE PAST FORECAST PACKAGE BECAUSE OF THESE CONCERNS. && .AVIATION.../06Z ISSUANCE/ WEST OF THE DIVIDE...MOIST WESTERLY FLOW SHOULD RESULT IN MVFR/IFR CONDITIONS DEVELOPING BETWEEN 10Z AND 14Z ACROSS FAR WESTERN WYOMING. SNOW WILL BE ON THE LIGHT SIDE...BUT MVFR AND BRIEF IFR CONDITIONS ARE EXPECTED FOR KJAC TERMINAL. KPNA AND KBPI COULD ALSO EXPERIENCE MVFR CONDITIONS TODAY...BUT CONFIDENCE IS NOT HIGH ENOUGH TO PREVAIL MVFR CONDITIONS IN THE TAF AT THE MOMENT. SNOW IS EXPECTED TO DECREASE IN COVERAGE LATE WEDNESDAY AFTERNOON...WITH VERY LIGHT SNOW/FLURRIES MAINLY IN THE MOUNTAINS WEDNESDAY TONIGHT...OCCASIONAL MAKING IT TO THE VALLEY FLOOR. MOUNTAINS WILL BE OBSCURED FOR MUCH IF NOT ALL OF THE FORECAST PERIOD. EAST OF THE DIVIDE...BREEZY TO VERY WINDY CONDITIONS WILL PREVAIL IN THE EASTERN SLOPES OF MOUNTAINS AND ADJACENT FOOTHILLS...AS WELL AS ACROSS THE WIND CORRIDOR FROM KRKS-KCPR. OTHERWISE VFR CONDITIONS ARE EXPECTED THROUGH THE FORECAST PERIOD WITH CONSIDERABLE HIGH CLOUDINESS AND SOME MID LEVEL CLOUDINESS AT TIMES. && .FIRE WEATHER... WINDY EAST OF THE DIVIDE THE NEXT COUPLE DAYS WITH SNOW AND WIND WEST OF THE DIVIDE. THE CODY FOOTHILLS CAN EXPECT HIGH WINDS THROUGH WEDNESDAY. THE SNOW WILL BE MAINLY LIGHT THROUGH WEDNESDAY NIGHT AND POTENTIALLY HEAVIER ON THURSDAY. A COLD FRONT WILL SLIDE SOUTH FOR AREAS EAST OF THE DIVIDE THURSDAY NIGHT WITH A CHANCE OF SNOW. && .RIW WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING FROM 5 PM THIS AFTERNOON TO 2 PM MST WEDNESDAY WYZ003. && SHORT TERM...SKRBAC LONG TERM...BRANHAM AVIATION...WM FIRE WEATHER...SKRBAC
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE RIVERTON WY 152 PM MST TUE JAN 24 2012 WYZ001>020-022>030-251200- 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- 152 PM MST TUE JAN 24 2012 ...HIGH WIND WARNING CODY FOOTHILLS TONIGHT THROUGH WEDNESDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL WYOMING. .DAY ONE...TODAY AND TONIGHT VERY STRONG TO POTENTIALLY DAMAGING WIND ARE EXPECTED TONIGHT ALONG THE CODY FOOTHILLS. WIND SPEEDS OF 30 TO 40 MPH WILL BLOW WITH GUSTS OVER 60 MPH. WIND GUSTS COULD EXCEED 80 TO 90 MPH FROM CLARK TO ABOUT 10 MILES SOUTH OF CLARK. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY WEDNESDAY...VERY STRONG TO DAMAGING WIND WILL CONTINUE ALONG THE CODY FOOTHILLS. SIGNIFICANT SNOWFALL MAY DEVELOP IN THE FAR WEST THURSDAY THROUGH THURSDAY EVENING. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY AND TONIGHT. TEAM RIVERTON
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE RIVERTON WY 552 PM MST TUE JAN 24 2012 WYZ023-250500- STAR VALLEY- 552 PM MST TUE JAN 24 2012 THROUGH MIDNIGHT...AREAS OF DENSE FOG WILL OCCUR ACROSS STAR VALLEY...ESPECIALLY BETWEEN SMOOT AND THAYNE...INCLUDING AFTON. VISIBILITY WILL BE REDUCED TO LESS THAN A QUARTER OF A MILE IN THE FOG. MOTORISTS SHOULD BE PREPARED FOR A SUDDEN REDUCTION IN VISIBILITY...SLOW DOWN AND USE LOW BEAMS WHEN FOG IS ENCOUNTERED... AND BE AWARE SOME BLACK ICE COULD BE PRESENT ON AREA ROADWAYS. 21
The national radar mosaic for the moment the first event began.
5 high wind. Local standard time, as filed.
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, January 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: 357650, 357646, 357648, 357647, 357649.