A tight pressure gradient and very strong winds aloft brought an extended period of high winds to portions of northwest and central Wyoming. The strongest winds were in the favored areas of the eastern foothills of the Absaroka Range.
Every event with a place to put it; 11 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 tight pressure gradient and very strong winds aloft brought an extended period of high winds to portions of northwest and central Wyoming. The strongest winds were in the favored areas of the eastern foothills of the Absaroka Range. The winds were strong enough to topple 13 high voltage transmission power poles west of Meeteetse Thursday night, February 5. The resulting power outage affected about 2,100 people. Muddy ground conditions prevented crews from getting equipment to where the towers fell, so some customers were without power until early Monday, February 9.
The strong winds continued on Friday, February 6. A mesonet anemometer five miles west-northwest of Clark had sustained winds of hurricane force for over an hour with a maximum wind gust of 114 mph. At least one home was damaged by the wind. Other strong wind gusts included 94 mph on Chief Joseph Pass, 82 mph at Fales Rock RAWS in southwest Natrona County, 78 mph at Red Canyon and Grass Creek Divide, and 74 mph in the North Fork Canyon along the east slopes of the Wind River Range.
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 Feb 5, 10:09 AM MST, 3 hours 21 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RIVERTON WY 1009 AM MST THU FEB 5 2015 .SHORT TERM...THURSDAY THROUGH SATURDAY NIGHT WITH THE CONTRAST IN WEATHER AND CONCERNS...WE WILL SPLIT THE SHORT TERM DISCUSSION BETWEEN WEST OF THE DIVIDE AND EAST OF THE DIVIDE. WEST OF THE DIVIDE...THINGS HAVE SETTLED DOWN SINCE YESTERDAY. THE POCATELLO RADAR STILL SHOWS A COUPLE OF SNOW SHOWERS AROUND THIS MORNING SO WE KEPT SOME POPS IN THROUGH THE MORNING. HOWEVER...THERE SHOULD BE A DECREASING TREND IN THE SHOWERS AS RIDGING BUILDS NORTHWARD ACROSS THE AREA. THEN...EXPECT MAINLY QUIET WEATHER FROM THIS AFTERNOON THROUGH MOST OF FRIDAY WITH FLAT RIDGING CONTROLLING THE WEATHER. THERE IS THE SMALL CHANCE IN THE FAR NORTHWEST THAT SOME WEAK DISTURBANCES TOPPING THE RIDGE COULD BRING A COUPLE OF SHOWERS BUT THESE SHOULD BE INSIGNIFICANT. TEMPERATURES SHOULD ALSO BE FAIRLY MILD...ALTHOUGH VALLEYS SHOULD BE COOLER WITH INVERSIONS FORMING AFTER GETTING A FRESH COVER OF SNOW. THE NEXT DECENT WEATHER MAKER LOOKS TO ARRIVE FRIDAY NIGHT IN THE FORM OF A PACIFIC COLD FRONT AND ASSOCIATED UPPER LEVEL DISTURBANCE. THIS SYSTEM DOES HAVE SOME DECENT MOISTURE TO WORK WITH...WITH A PACIFIC ORIGIN. THERE WILL ALSO BE SOME DECENT UPPER LEVEL SUPPORT WITH THE LEFT FRONT QUADRANT OF A JET MOVING INTO SOUTHWESTERN WYOMING. HOWEVER...WITH THE ORIGIN THIS WILL ALSO BRING IN SOME WARMER AIR THAT COULD CAUSE SOME PRECIPITATION TYPE PROBLEMS. THE NAM SHOWS 700 MILLIBAR TEMPERATURES RISING TO BETWEEN MINUS 3 AND 3.5 DEGREES CELSIUS BY SATURDAY AFTERNOON. THIS WOULD PUT SNOW LEVELS BETWEEN 6500 AND 7000 FEET AND KEEP ACCUMULATIONS DOWN IN THE VALLEYS. FOR NOW...CONTINUITY REFLECTED THIS FAIRLY WELL AND WE DID NOT MAKE A LOT OF CHANGES. THE MODELS THEN DIVERGE FOR SUNDAY NIGHT WITH THE DETAILS...SO AGAIN NOT A LOT OF CHANGE TO CONTINUITY. EAST OF THE DIVIDE...ALL IN ALL...ANOTHER FAIRLY DRY FORECAST WITH THE EXCEPTION OF SOME LIGHT SNOW IN THE BIG HORN RANGE. HOWEVER...THERE ARE OTHER CONCERNS. FIRST...IS THE DREADED FOG MONSTER. WITH THE SNOW OF YESTERDAY ALONG WITH SOME MELTING...THERE HAS ALREADY BEEN SOME FOG THAT HAS DEVELOPED AROUND RIVERTON AND THE WIND RIVER BASIN. THERE COULD STILL BE SOME IN THE FAVORED LOW LYING LOCATIONS THIS MORNING WITH VERY SMALL TEMPERATURE-DEW POINT SPREADS. PATCHY FOG WAS IN THE FORECAST AND THIS WAS KEPT. AND THIS LEADS TO THE SECOND PROBLEM...HIGH TEMPERATURES FOR THE NEXT COUPLE OF DAYS. WITH THE FRESH SNOW AND NOW SOME LOW CLOUDS AND FOG FORMING THERE COULD BE LIMITED MIXING ACROSS THE BASINS. THE RESULT IS THE TERM MANY PEOPLE DO NOT WANT TO HEAR...INVERSION. WITH TEMPERATURES ALREADY IN THE TEENS AND WITH LIMITED MIXING EXPECTED...WE LOWERED HIGH TEMPERATURES IN THE BASINS BY SEVERAL DEGREES. NOW...THE SUN IS STRONGER NOW THAN IN EARLY JANUARY SO THERE IS A BETTER CHANCE THAT IT COULD BREAK. HOWEVER...WE KEPT TEMPERATURES COOLER SINCE IF IT DOES WARM UP...MOST PEOPLE WILL BE HAPPY. THE CHANCE OF THE INVERSION BREAKING SHOULD INCREASE EACH DAY THROUGH SATURDAY...THE START OF THE WEEKEND LIKELY BEING THE WARMEST DAY. ACROSS AREAS THAT ARE NORMALLY WINDIER...AKA THE SOUTHWESTERN WIND CORRIDOR AND EAST OF THE ABSAROKAS AND BIG HORN RANGE...SHOULD WARM UP. AND IT COULD GET QUITE TOASTY HERE. SOME OF THE MODEL GUIDANCE HAS HIGH TEMPERATURES IN THE 60S BY SATURDAY. AND THIS LEADS US TO THE THIRD AND PROBABLY THE MOST IMPACTFUL OF THE THREE PROBLEMS. AND NUMBER THREE IS THE POTENTIAL FOR HIGH WINDS. AND THIS WILL BE ACROSS THE MOST OBVIOUS SUSPECTS. THE FIRST PLACE SHOULD BE OBVIOUS TO REGULAR READERS OF THESE DISCUSSIONS. THE MOST WIND PRONE PLACE IN THE COUNTY WARNING AREA...THE CODY FOOTHILLS MAINLY AROUND THE GREAT CROSSROAD OF CLARK. THE MODELS SHOW 700 MILLIBAR WINDS INCREASING TO OVER 50 KNOTS BY LATE TODAY WITH SOME MODELS SHOWING INCREASES TO AS MUCH AS 70 KNOTS BY LATE TONIGHT AND FRIDAY MORNING. CROSS SECTIONS ALSO SHOW A BIT OF A MOUNTAIN WAVE SIGNATURE. AS A RESULT...WE WILL CONTINUE THE HIGH WIND WATCH FOR ZONE 3. THIS COULD BE A LONG LIVED EVENT AS WELL WITH THE STRONG WINDS POSSIBLY INCREASING AGAIN FRIDAY NIGHT BEFORE DECREASING SATURDAY MORNING AFTER THE PASSAGE OF THE SHORTWAVE AND SOME COLD ADVECTION WEAKENING THE WINDS A BIT. THE OTHER CONCERN IS THE SOUTHWESTERN WIND CORRIDOR FROM NEAR ROCK SPRINGS TO CASPER. HERE...THERE IS MORE UNCERTAINTY. ONE...THE WINDS ARE NOT WELL ALIGNED FROM THE SURFACE TO THE MID LEVELS. HOWEVER...THERE ARE SOME 50 TO 60 KNOT WIND BARBS...ESPECIALLY FROM FRIDAY AFTERNOON INTO SATURDAY. AT THIS POINT...MY GUT FEELING IS MOST PLACES WOULD FALL SHORT. THE EXCEPTIONS WOULD BE PLACES LIKE FALES ROCK AND CAMP CREEK BUT THERE IS NOTHING BUT BEARS AND DEER THERE THIS TIME OF YEAR. ANOTHER PLACE WOULD BE OUTER DRIVE SOUTH OF CASPER...WHERE THIS WOULD BE MORE PROBLEMATIC. HOWEVER...THERE IS ENOUGH TIME TO WATCH IT AT THIS POINT. STAY TUNED. .LONG TERM...SUNDAY THROUGH THURSDAY NIGHT SNOW ACROSS THE WEST WILL BE WINDING DOWN SUNDAY...AS A TRANSITORY RIDGE QUICKLY BUILDS OVER THE NORTHERN ROCKIES. H7 TEMPS WILL REMAIN BETWEEN -2 AND -4...HOWEVER ADDITIONAL SNOW AMOUNTS WILL BE AN INCH OR LESS. EAST OF THE DIVIDE WILL BE WARM AND DRY SUNDAY AND MONDAY...WITH AFTERNOON HIGHS IN THE UPPER 40S TO MIDDLE 50S. BREEZY WINDS WITH GUSTS UP TO 25 MPH WILL OCCUR FROM EASTERN SWEETWATER TO NATRONA COUNTY SUNDAY...AND RETURN AGAIN MONDAY AFTERNOON FOR NATRONA COUNTY AND SOUTHEASTERN FREMONT COUNTY. OTHERWISE...PLEASANT CONDITIONS TO END THE WEEKEND AND BEGIN THE WORK WEEK. THESE CONDITIONS WILL BE SHORT-LIVED...AS ANOTHER MAJOR PACIFIC STORM SYSTEM MAKES ITS WAY ONSHORE OVER THE PACIFIC NORTHWEST. MOISTURE ASSOCIATED WITH THE SYSTEM...WILL IMPACT WESTERN PORTIONS MONDAY AFTERNOON...INTO TUESDAY MORNING. A COLD FRONT WILL MOVE THROUGH THIS AREA BY LATE MONDAY AFTERNOON...QUICKLY TURNING ANY VALLEY RAIN OVER TO SNOW DURING THE EVENING HOURS. PRECIPITATION WILL SPREAD EAST OF THE DIVIDE INTO CENTRAL PORTIONS DURING THE OVERNIGHT HOURS...STARTING OUT AS RAIN...BEFORE TURNING TO A RAIN/SNOW MIX. SOUTHERN PORTIONS WILL CHANGE OVER TO SNOW BY MIDNIGHT TUESDAY...WHILE SOME AREAS FROM ALONG THE FREMONT/NATRONA COUNTY LINE SOUTHWARD INTO EASTERN SWEETWATER COUNTY...REMAIN A RAIN/SNOW MIX. MOST AREAS ACROSS THE FORECAST AREA WILL CHANGE OVER TO SNOW BY SUNRISE TUESDAY MORNING. DUE TO THE PACIFIC NATURE OF THIS SYSTEM...TEMPERATURES WILL MODERATE A BIT DURING THE DAY...ALLOWING FOR THE SNOW TO CHANGE BACK OVER TO RAIN. THIS WILL NOT OCCUR OVER WESTERN PORTIONS HOWEVER. PRECIPITATION CHANCES WILL END OVERNIGHT TUESDAY...AS THE SYSTEM BEGINS TO CLOSE OFF AND MOVE SOUTH OVER THE GREAT BASIN AND FOUR CORNERS REGION. A RIDGE WILL BUILD OVER THE PACIFIC NORTHWEST AND BE IN PLACE BY THURSDAY. THIS WILL KEEP A DRY NORTH-NORTHWEST FLOW ACROSS THE NORTHERN ROCKIES THROUGH THE REST OF THE FORECAST PERIOD. THIS ALSO HAS THE POTENTIAL TO SET UP A REX BLOCK OVER THE WESTERN CONUS...WHICH COULD KEEP THINGS DRY GOING INTO THE MIDDLE OF FEBRUARY. && .AVIATION.../18Z ISSUANCE/ EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES VFR CONDITIONS PREVAILING THROUGH THE FORECAST PERIOD WITH THE EXCEPTION OF SOME PATCHY FOG IN THE LOWER BASINS AGAIN EARLY FRIDAY MORNING. OTHERWISE...RIDGE TOP WINDS WILL INCREASE THROUGH THE DAY...35-45KTS BETWEEN 7.5KFT AND 12KFT OVER THE EAST SLOPES OF THE DIVIDE...VCNTY KCOD-KLND THROUGH FRIDAY MORNING...RESULTING IN AREAS OF LLWS/MTN WAVE ACTIVITY...WITH STRONGER WINDS LIKELY MIXING DOWN TO THE SFC VCNTY KCOD BY 03Z FRIDAY. WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST PERIOD WITH THE EXCEPTION OF SOME PATCHY FOG IN THE LOWER BASINS AGAIN EARLY FRIDAY MORNING. ISOLD -SHSN OVR THE MTNS WILL CONTINUE TO DECREASE THIS AFTERNOON. MTN TOP WINDS...ABV 10KFT...WILL INCREASE TO 45-60 KTS THIS AFTN RESULTING IN SOME MTN WAVE ACTIVITY AND LCL LLWS...ESPECIALLY VCNTY KJAC-KBPI ROUTES THIS AFTERNOON THROUGH THURSDAY NIGHT. && .FIRE WEATHER... EXPECT INVERSIONS ALONG WITH LOW MIXING HEIGHTS AND POOR SMOKE DISPERSION ACROSS THE DEEPER VALLEYS AND BASINS TODAY WITH THE FRESH SNOW COVER. MIXING WILL BE BETTER ACROSS THE SOUTHWESTERN WIND CORRIDOR FROM THE RED DESERT TO NATRONA COUNTY AND IN THE LEE OF THE ABSAROKAS. EXPECT MAINLY DRY WEATHER EVERYWHERE THROUGH FRIDAY WITH THE NEXT CHANCE OF SNOW ARRIVING IN WESTERN WYOMING FRIDAY NIGHT. && .RIW WATCHES/WARNINGS/ADVISORIES... HIGH WIND WATCH FROM 6PM MST THIS EVENING THROUGH SATURDAY MORNING WYZ002-003-016. && SHORT TERM...HATTINGS LONG TERM...LAVOIE AVIATION...JB FIRE WEATHER...HATTINGS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE RIVERTON WY 818 AM MST THU FEB 5 2015 WYZ001>020-022>030-061200- 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- 818 AM MST THU FEB 5 2015 ...DENSE FOG ADVISORY FOR PORTIONS OF THE WIND RIVER BASIN THROUGH 10AM... ...HIGH WIND WATCH FOR THE CODY FOOTHILLS...ABSAROKA MOUNTAINS AND WESTERN WIND RIVER BASIN FROM THIS EVENING THROUGH SATURDAY MORNING... THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL WYOMING. .DAY ONE...TODAY AND TONIGHT AREAS OF FOG ACROSS THE VALLEYS AND BASINS THIS MORNING. DENSE FOG WILL OCCUR IN THE WIND RIVER BASIN. STRONG TO POTENTIALLY DAMAGING WINDS WILL INCREASE OVER THE ABSAROKA MOUNTAINS...ALONG THE CODY FOOTHILLS...AND IN THE WESTERN WIND RIVER BASIN LATER THIS EVENING INTO THE OVERNIGHT HOURS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY FRIDAY AND SATURDAY...STRONG TO HIGH WINDS AT TIMES IN THE MOUNTAINS...WIND CORRIDOR FROM JEFFREY CITY TO CASPER AND ALONG THE CODY FOOTHILLS. SATURDAY AND SATURDAY NIGHT...SIGNIFICANT SNOWFALL MAY FALL IN THE WESTERN MOUNTAINS ALONG WITH STRONG WIND. MONDAY NIGHT AND TUESDAY...SIGNIFICANT SNOW RETURNS TO WESTERN PORTIONS. RAIN CHANGING TO SNOW WILL BE POSSIBLE EARLY MONDAY EVENING FOR THE WESTERN VALLEYS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT NEEDED AT TIME. TEAM RIVERTON
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE RIVERTON WY 836 AM MST THU FEB 5 2015 WYZ025-026-051700- UPPER GREEN RIVER BASIN-UPPER GREEN RIVER BASIN FOOTHILLS- 836 AM MST THU FEB 5 2015 AREAS OF FOG...SOME LOCALLY DENSE WILL BE FOUND THROUGH 9 AM. TRAVELERS SHOULD BE ALERT FOR AREAS OF DENSE FOG WITH VISIBILITIES DOWN TO ONE QUARTER MILE. SLOW DOWN AND ALLOW EXTRA TIME TO REACH YOUR DESTINATION. IN ADDITION...MOTORISTS SHOULD BE ALERT FOR A FEW SLICK SPOTS ON AREA HIGHWAYS. JB
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE RIVERTON WY 1145 AM MST THU FEB 5 2015 WYZ017-052100- WIND RIVER BASIN- 1145 AM MST THU FEB 5 2015 AREAS OF PATCHY DENSE FOG WILL BE FOUND THROUGH 2 PM. TRAVELERS SHOULD BE ALERT FOR SMALL AREAS WITH VISIBILITIES DOWN TO ONE QUARTER MILE. SLOW DOWN AND ALLOW EXTRA TIME TO REACH YOUR DESTINATION. IN ADDITION...MOTORISTS SHOULD BE ALERT FOR A FEW SLICK SPOTS ON AREA HIGHWAYS. JB
The national radar mosaic for the moment the first event began.
11 high wind. Local standard time, as filed.
The peak wind on Chief Joseph Pass was clocked at 86 mph.
Wind gusts to near 100 mph toppled power poles and caused power outages in rural areas around Meeteetse.
A sensor on Chief Joseph Pass registered a wind gust to 94 mph.
Sustained hurricane force winds with several gusts in excess of 100 mph occurred west-northwest of Clark. The wind caused damage to at least one home.
The wind sensor at Outer Drive near Casper had a wind gust to 72 mph. Other strong wind gusts included 62 mph at Hiland, and 59 mph at the Casper-Natrona County International Airport.
A wind gust of 74 mph was recorded at a ranch along the North Fork of the Popo Agie River. The ASOS at the Lander Airport had a wind gust of 59 mph.
Strong winds occurred in portions of the Green and Rattlesnake ranges. The highest wind gust recorded was 82 mph at Fales Rock RAWS. Gusts to 65 mph were recorded at Beaver Rim and Camp Creek RAWS.
A 78 mph wind gust was recorded at Red Canyon.
The wind sensor on Interstate 25 north of Kaycee measured several wind gusts past 58 mph including a maximum of 68 mph.
A wind gust of 76 mph was recorded at Grass Creek Divide RAWS.
The weather sensor at Piney Creek had a wind gust of 65 mph. The ASOS at the Buffalo Airport had a wind gust to 58 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2015Every state in 2015This day in weather historyWarnings in Wyoming, February 2015
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: 552527, 552528, 563195, 563196, 552530, 552532, 552529, 552531, 552534, 552535, 552533.