A strong low pressure system and associated cold front moved through Wyoming on Tuesday, October 16, and brought strong wind gusts to many locations east of the Continental Divide. Wind gusts to over 100 mph were reported on some ridgetops with wind gusts routinely topping 60 mph, and in some cases 75 mph, across the lower elevations.
Every event with a place to put it; 7 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 RIW wrote it up.
A strong low pressure system and associated cold front moved through Wyoming on Tuesday, October 16, and brought strong wind gusts to many locations east of the Continental Divide. Wind gusts to over 100 mph were reported on some ridgetops with wind gusts routinely topping 60 mph, and in some cases 75 mph, across the lower elevations.
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 Oct 16, 2:47 AM MST, 2 hours 13 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RIVERTON WY 347 AM MDT TUE OCT 16 2012 .SHORT TERM...TODAY THROUGH THURSDAY NIGHT THE LOW SPINNING AT 54N/139W WILL SWING A VIGOROUS SHORTWAVE TROUGH ACROSS THE CWA TODAY AS THE PARENT LOW CLOSES OFF AND TRACKS SOUTHEAST ACROSS SASKATCHEWAN. THIS SHORTWAVE WILL PUSH A STRONG COLD FRONT ACROSS THE AREA THIS EVENING. WEST SOUTHWEST WINDS WILL INCREASE AS THE PRESSURE GRADIENT TIGHTENS AHEAD OF THE APPROACHING ASSOCIATED COLD FRONT. THE COLD FRONT PUSHES SOUTH ACROSS THE MONTANA BORDER AROUND 00Z WEDNESDAY AND ACROSS CENTRAL WYOMING 06Z WEDNESDAY. THE HIGH WIND WATCH HAS BEEN UPGRADED TO A WARNING ACROSS MUCH OF CENTRAL AND SOUTHERN WYOMING FOR TODAY. WILL ALSO LET THE HIGH WIND WARNING IN PARK COUNTY RIDE THROUGH THE DAY TODAY ALTHOUGH THE MOST PERSISTENT HIGH WINDS SHOULD OCCUR EARLIER IN THE DAY TODAY. THE HIGH WINDS IN CLARK IN NORTHERN PARK COUNTY AND THE ADJACENT ABSAROKA MOUNTAINS WILL TRANSITION TO A GRADIENT WIND LATER THIS MORNING. ONCE THE FRONT PUSHES ON THROUGH...THERE WILL BE A QUICK BLAST OF NORTHWEST THEN NORTH WINDS AS 11MB 3 HOURLY SURFACE PRESSURE RISES OCCUR AFTER THE FROPA THIS EVENING. THEN ONCE THE PARENT LOW TRACKS SOUTHEAST FROM SASKATCHEWAN TO MANITOBA AND STRENGTHENS...THE GRADIENT WILL TIGHTEN ON THE BACK SIDE OF THE LOW INCREASING THE NORTHWEST WIND FAVORED AREAS...ESPECIALLY IN NORTHERN JOHNSON COUNTY WHERE A HIGH WIND WATCH HAS BEEN ISSUED FROM 15Z WEDNESDAY THROUGH 03Z THURSDAY. DURING THIS TIME FRAME...6 30 METER HEIGHT CONTOURS AT 700MB WILL BE FOUND OVER WYOMING...A GOOD INDICATION OF A STRONG GRADIENT WIND. AS FOR PRECIPITATION ASSOCIATED WITH THIS WEATHER SYSTEM...IT APPEARS THAT UP TO AROUND ONE HALF OF AN INCH OF PRECIPITATION WILL FALL OVER PORTIONS OF THE WESTERN MOUNTAINS AND THE BIG HORN MOUNTAINS TODAY AND THIS EVENING. INCREASING WESTERLY DIFLUENT FLOW OCCURRING AHEAD OF THE APPROACHING TROUGH WILL AID IN LIFT IN ADDITION TO THE STRONG WESTERLY UPSLOPE COMPONENT. THEN THE PRECIP WILL BREAK OUT EAST OF THE DIVIDE AHEAD OF AND ALONG THE APPROACHING FRONT BY THIS AFTERNOON. ANY SNOW THAT FALLS IN THE MOUNTAINS WILL BE MAINLY ON THE LIGHT SIDE WITH POCKETS OF UP TO 5 TO 10 INCHES AT THE HIGHEST ELEVATIONS ABOVE 10000 FEET. WITH H7 TEMPS DROPPING TO -10 IN NORTHEAST WYOMING WEDNESDAY...TEMPERATURES WILL BE AROUND 20 DEGREES COLDER WEDNESDAY THEN TODAY. EXPECT DRY CONDITIONS AND A SLIGHT WARM UP THURSDAY AS HIGH PRESSURE BUILDS IN FROM THE WEST. .LONG TERM...FRIDAY THROUGH TUESDAY MEDIUM RANGE MODELS ARE DRAMATICALLY DIFFERENT TONIGHT WITH MOST OF THE CHANGES SHOWING UP BETWEEN THE 18Z RUNS AND THE 00Z RUNS. VERY COMPLEX CHALLENGING HEMISPHERIC PATTERN TO FORECAST WITH MORE RETROGRESSION SHOWING UP IN THE MODELS TONIGHT AND DRAMATICALLY DIFFERENT UPSTREAM PATTERN AND EASTERN PACIFIC...ALASKA RIDGE DEVELOPMENT. THE ECMWF STILL HAS MORE SHORTWAVE ENERGY MOVING THROUGH THE SW FLOW TO KEEP THE POTENTIAL FOR THE CANADIAN COLD FRONT TO SAG SWD INTO AREAS EAST OF THE DIVIDE AS EARLY AS SUNDAY AND THEN REMAIN IN PLACE THROUGH AT LEAST THE END OF THE MEDIUM RANGE PERIOD AND POSSIBLY BEYOND. THE GFS HAS A WEAKER BOUNDARY SAGGING SOUTH SUNDAY AND HOLDING INTO MONDAY BEFORE BEING WASHED OUT IN THE DEVELOPING SOUTHWEST FLOW. THE DIFFERENCES ON TUESDAY COULDN'T BE MUCH MORE DRAMATIC WITH THE GFS SHOWING A WARM SW FLOW AND H7 TEMPERATURES AROUND +8C WHILE THE ECMWF STILL HAS THE COLD FRONT ENTRENCHED WITH H7 TEMPERATURE AS COLD AS -10C ACROSS THE NORTH TO A AROUND ZERO ALONG THE UTAH BORDER. THE GFS HAS BACKED OFF ON THE STRENGTH OF THE SURFACE HIGH TO THE NORTH WHILE THE ECMWF STILL HAS A 1045MB OR GREATER SURFACE HIGH COMING INTO PLAY. FORECAST IS LEANING MORE TOWARDS SOME UPSLOPE CONTINUING EAST OF THE DIVIDE EARLY NEXT WEEK WITH A CHANCE OF RAIN OR SNOW BUT CONFIDENCE ON THE DETAILS IS LOW WITH THE COMPLEXITY OF THE UPPER PATTERN AND THE MODELS INABILITY TO HANDLE IT. THE MEDIUM RANGE PERIODS SHOULD BEGIN QUITE MILD FRIDAY AND SATURDAY WITH THE POTENTIAL FOR DRAMATIC CHANGE TO COLDER AND UNSETTLED WEATHER EARLY NEXT WEEK...ESPECIALLY NORTH AND EAST. && .AVIATION.../12Z ISSUANCE/ A STRONG WEATHER SYSTEM WILL MOVE THROUGH THE REGION TODAY INTO TONIGHT. WINDY CONDITIONS WILL OCCUR IN MANY PLACES TODAY AND TONIGHT. EXPECT WIND GUSTS OF 30 TO 40 KNOTS AT MANY LOCATIONS...WITH LOCAL GUSTS UP TO 50 KNOTS. RAIN AND SNOW WILL OCCUR IN WESTERN WY TODAY WITH THE PRECIPITATION PUSHING EAST OF THE DIVIDE AFTER 20Z AS THE COLD FRONT PROGRESSES EAST. MVFR TO IFR CONDITIONS WILL BE COMMON IN THE HIGH COUNTRY WITH MOUNTAIN OBSCURATION. MVFR CONDITIONS WILL OCCUR AT THE KJAC TERMINAL SITE BY 18Z AND CONTINUING THROUGH 00Z...THEN IMPROVING CONDITIONS TO VFR BY 03Z. CHECK THE LATEST OBSERVATIONS AND TERMINAL FORECASTS TODAY AS CONDITIONS WILL BE CHANGING RAPIDLY AS THIS WEATHER SYSTEM BLOWS THROUGH THE AREA. && .FIRE WEATHER... EXPECT VERY STRONG WEST WINDS TODAY AND THIS EVENING ACROSS MUCH OF WESTERN AND CENTRAL WYOMING AS A STRONG COLD FRONT PUSHES SOUTH ACROSS WYOMING. RAIN SHOWERS AND HIGH ELEVATIONS SNOW SHOWERS WHICH WILL BEGIN OVER WESTERN WYOMING THIS MORNING WILL SPREAD SOUTH AND EAST ACROSS THE STATE AS THE FRONT PUSHES SOUTH. AS THE PARENT LOW PRESSURE CENTER THAT WILL SWING THE COLD FRONT ACROSS THE AREA TODAY TRACKS SOUTHEAST TO SASKATCHEWAN AND MANITOBA...NORTHWEST WINDS WILL INCREASE AROUND THE BACK SIDE OF THE LOW...ESPECIALLY IN NORTHERN ZONE 281. AS FOR PRECIPITATION ASSOCIATED WITH THIS WEATHER SYSTEM...IT APPEARS THAT UP TO AROUND ONE HALF OF AN INCH OF PRECIPITATION WILL FALL OVER PORTIONS OF THE WESTERN MOUNTAINS AND THE BIG HORN MOUNTAINS TODAY AND THIS EVENING. THEN THE PRECIP WILL BREAK OUT EAST OF THE DIVIDE AHEAD OF AND ALONG THE APPROACHING FRONT. ANY SNOW THAT FALLS IN THE MOUNTAINS WILL BE MAINLY ON THE LIGHT SIDE WITH POCKETS OF UP TO 5 TO 10 INCHES AT THE HIGHEST ELEVATIONS ABOVE 10000 FEET. TEMPERATURES WILL BE AROUND 20 DEGREES COLDER WEDNESDAY THEN TODAY. EXPECT DRY CONDITIONS AND A SLIGHT WARM UP THURSDAY AS HIGH PRESSURE BUILDS IN FROM THE WEST. && .RIW WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL 6 PM MDT THIS EVENING WYZ002-003. HIGH WIND WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING WYZ016>018-028>030. HIGH WIND WARNING FROM 9 AM THIS MORNING TO 9 PM MDT THIS EVENING WYZ019. HIGH WIND WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY EVENING WYZ010. HIGH WIND WARNING UNTIL 6 PM MDT THIS EVENING WYZ015. && SHORT TERM...LIPSON LONG TERM...SKRBAC AVIATION...AR FIRE WEATHER...LIPSON
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE RIVERTON WY 508 AM MDT TUE OCT 16 2012 WYZ001>020-022>030-171200- 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- 508 AM MDT TUE OCT 16 2012 ...HIGH WIND WARNING FOR THE ABSAROKA MOUNTAINS AND CODY FOOTHILLS THROUGH TODAY AND FOR MUCH OF CENTRAL AND SOUTHERN WYOMING TODAY THROUGH THIS EVENING... ...HIGH WIND WATCH FOR WEDNESDAY FOR NORTHERN JOHNSON COUNTY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL WYOMING. .DAY ONE...TODAY AND TONIGHT TODAY AND THIS EVENING...VERY STRONG WINDS ARE EXPECTED ALONG THE EAST SLOPE OF THE WIND RIVER AND ABSAROKA MOUNTAINS INCLUDING THE NEARBY CODY FOOTHILLS INCLUDING THE TOWN OF CLARK AS WELL AS ACROSS MUCH OF THE LOWER ELEVATIONS OF CENTRAL AND SOUTHERN WYOMING. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY WEDNESDAY...VERY STRONG WINDS ARE POSSIBLE ACROSS NORTHERN JOHNSON COUNTY. .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT ANY WIND GUSTS OVER 50 MPH TODAY...AS WELL AS ANY WIND DAMAGE THAT MAY OCCUR. TEAM RIVERTON
The national radar mosaic for the moment the first event began.
7 high wind. Local standard time, as filed.
The North Zone RAWS site reported a wind gust of 113 mph at an elevation of 10750 feet.
Strong wind gusts of 78 and 77 mph were reported at Chief Joseph.
A 71 mph was reported at the Fales Rock RAWS station. A gust of 72 mph was reported at the Camp Creek RAWS station.
High winds blew for several hours across the lower elevations of Natrona County. The WYDOT weather sensor at Highland reported sustained winds as high as 52 mph with gusts as high as 76 mph. The Casper Airport reported a wind gust to 60 mph.
A wind gust to 59 mph was recorded at an automated station on the west side of Cody. In addition, winds were sustained at 42 mph at Meeteetse with gusts to 58 mph.
A wind gust of 63 mph was reported at the Snow Springs RAWS.
A wind gust of 75 mph was reported at the Riverton Airport. A National Weather Service employee also reported a wind gust of 62 mph at 1527LST at the Riverton Country Club.
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, October 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: 412957, 412955, 412959, 413954, 412956, 412961, 412958.