A tightening pressure gradient and eventually the passage of a cold front brought strong winds to northern and central Wyoming. The strongest winds were in the favored areas near Clark, where a few wind gusts were hurricane force in advance of the cold front.
Every event with a place to put it; 5 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 tightening pressure gradient and eventually the passage of a cold front brought strong winds to northern and central Wyoming. The strongest winds were in the favored areas near Clark, where a few wind gusts were hurricane force in advance of the cold front. Peak speeds ranged from 63 to 84 mph. Gusts in the nearby Absaroka Range reached 78 mph. Southwest flow ahead of the cold front combined with favorable atmospheric conditions to generate a mountain wave in the Lander Foothills Saturday afternoon, March 28. A peak gust to 71 mph was measured at Hunt Field in Lander, damaging at least one metal-sided garage in town. In southern Johnson County, peak speeds reached 62 mph ahead of the cold front. Strong northwest wind struck the northern end of Johnson County in the wake of the cold front, with a 60 mph gust registered at the airport in Buffalo.
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 Mar 28, 10:07 AM MST, 29 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RIVERTON WY 1107 AM MDT SAT MAR 28 2015 .SHORT TERM...SATURDAY THROUGH MONDAY NIGHT SATURDAY STILL LOOKS TO BE THE MOST ACTIVE OF THE NEXT FEW DAYS. THE CULPRITS ARE A VIGOROUS TROUGH AS WELL AS AN ASSOCIATED COLD FRONT CURRENTLY LOCATED OVER WASHINGTON AND OREGON THAT WILL RACE ACROSS THE AREA THIS AFTERNOON AND TONIGHT. THERE IS SOME INSTABILITY AS IT MOVES ACROSS. HOWEVER...IT IS LACKING DEEP MOISTURE WITH MOST OF THAT MOVING ACROSS NORTHERN MONTANA AND SOUTHERN CANADA. AS A RESULT...WE ANTICIPATE ONLY A FEW SHOWERS ACROSS NORTHERN PORTIONS OF WYOMING THIS AFTERNOON AND EVENING. HOWEVER...THE BIG STORY WILL BE THE WIND AS HATS AND TOUPEES WILL BE FLYING AROUND THIS AFTERNOON IF NOT SECURED. THERE ARE 3 FACTORS THAT WILL COME TOGETHER FOR A WINDY DAY ACROSS MUCH OF THE AREA. THE FIRST IS THE TIGHT PRESSURE GRADIENT AS LOW PRESSURE DEVELOPS JUST TO THE NORTH OF THE AREA. THE SECOND IS INCREASING 700 MILLIBAR WINDS WITH VELOCITIES UP TO 50 TO 60 KNOTS IN MANY AREAS. WITH GOOD MIXING EXPECTED WITH THE FRONTAL PASSAGE THESE WILL LIKELY MIX TO THE SURFACE. IN ADDITION...THE AREA WILL BE IN THE FAVORED RIGHT FRONT QUADRANT OF A 90-95 KNOT JET STREAK THIS AFTERNOON THAT WILL ENHANCE DOWNWARD MOMENTUM. WITH THESE CONDITIONS...WE WILL UPGRADE THE HIGH WIND WATCH TO A WARNING WITH THE ISSUANCE OF THE PACKAGE THIS MORNING. THE MOST FAVORED AREA IS ACROSS NORTHERN JOHNSON COUNTY WHICH IS FAVORED WITH NORTHWESTERLY FLOW AFTER FRONTAL PASSAGES. ELSEWHERE...WINDS SHOULD FALL SHORT ALTHOUGH STRONG GUSTS ARE POSSIBLE IN AREAS LIKE THE CODY FOOTHILLS AND EVEN THE WIND RIVER BASIN. WITH THE DOWNSLOPING FLOW IT WILL ALSO BE A VERY WARM DAY WITH RECORD HIGH TEMPERATURES A DECENT POSSIBILITY FOR MANY AREAS. THE RED FLAG WARNING ALSO LOOKS GOOD AND WILL BE CONTINUED AS IS. THE TIME OF THE STRONGEST WINDS SHOULD LATE THIS AFTERNOON THROUGH THIS EVENING BEFORE THE FORCING AND PRESSURE GRADIENT DECREASE. MAINLY QUIET WEATHER SHOULD RETURN FOR SUNDAY AND MONDAY AS HIGH PRESSURE AND WEAK RIDGING BUILD BACK OVER THE COWBOY STATE. THERE COULD STILL BE LOCALLY BREEZY CONDITIONS IN FAVORED AREAS BUT NOTHING LIKE SATURDAY AFTERNOON. TEMPERATURES WILL ALSO COOL DOWN SOMEWHAT BEHIND THE FRONT...BUT STILL REMAIN ABOVE NORMAL FOR LATE MARCH. .LONG TERM...TUESDAY THROUGH SATURDAY TUESDAY LOOKS BREEZY TO WINDY AND WARM AHEAD OF THE NEXT WEATHER SYSTEM. ISOLATED SHOWERS MAY DEVELOP IN FAR WEST WY MID TO LATE AFTERNOON. AS THE FRONT BLOWS THROUGH WY TUE NIGHT SOME SHOWERS AND ISOLATED STORMS WILL OCCUR MAINLY OVER THE NORTH AND CENTRAL WITH ISOLATED ACTIVITY OVER THE SOUTH. EXPECT IT TO BE BREEZY TO WINDY TUESDAY NIGHT AFTER THE FRONTAL PASSAGE. THE ECMWF MODEL IS A LITTLE SLOWER WITH THIS FRONTAL PASSAGE. THE GFS KEEPS THE WEATHER UNSETTLED ACROSS THE NORTH HALF OF THE STATE WEDNESDAY INTO WED NIGHT WITH SOME SHOWERS AND ISOLATED STORMS. FOR NOW THE ACTIVITY WOULD BE ALONG AND NORTH OF A LINE FROM JACKSON TO MIDWEST. THE ECMWF MODEL IS A LITTLE DRIER OVER THE NORTH WED AND WED NIGHT BUT DOES KEEP NW WY WITH THE BEST CHANCE OF SHOWERS. THE GFS KEEPS ISOLATED SHOWERS IN THE FORECAST THURSDAY WITH A WEATHER DISTURBANCE MOVING THROUGH THE AREA. THE ECMWF MODEL HAS MORE OF A DIGGING TROUGH INTO THE GREAT BASIN THURS INTO THURS NIGHT. THIS LEADS TO A WETTER SCENARIO OVER THE REGION. HAVE USED A BLEND OF THE SOLUTIONS AND HAVE A CHANCE OF SHOWERS FOR NOW. THE GFS HAS A WEST FLOW ALOFT FOR FRIDAY WITH DRY CONDITIONS. THE ECMWF MODEL KEEPS A NW FLOW OVER THE AREA AND LINGERING ISOLATED SHOWERS. HAVE OPTED TO KEEP IT DRY AND ONLY ISOLATED SHOWERS OVER THE NW CORNER OF WY. THEN NEXT SATURDAY THE GFS HAS A WEST TO SOUTHWEST FLOW ALOFT WITH ISOLATED SHOWERS/STORMS FOR PLACES WEST OF THE DIVIDE. THE ECMWF IS DRY WITH A BIT OF AN UPPER RIDGE OVER THE REGION. WILL GO WITH ISOLATED SHOWERS FAR WEST NEXT SATURDAY. AFTER THE WARM AND WELL ABOVE NORMAL TEMPS TUESDAY...HIGH TEMPS WILL BE COOLER AND MORE TOWARD SEASONAL VALUES FOR WED THROUGH FRIDAY. THEN A LITTLE WARMER NEXT SATURDAY. && .AVIATION.../18Z ISSUANCE/ VFR CONDITIONS WILL PREVAIL THROUGH 18Z SUNDAY. A STRONG BUT MAINLY DRY COLD FRONT WILL PUSH ACROSS THE AREA THIS AFTERNOON. A LINE OF SHOWERS AND POSSIBLY A THUNDERSTORM OR TWO IS EXPECTED TO DEVELOP AHEAD OF OR ALONG THE FRONT...MOVING RAPIDLY EAST VICINITY AND NORTH OF A KCOD-KGCC LINE DURING THE AFTERNOON. THESE SHOWERS ARE EXPECTED TO BE HIGH-BASED WITH CEILINGS FL120-140...WITH SOME HIGHER MOUNTAIN OBSCURATIONS ACROSS THE ABSAROKA AND BIGHORN RANGES. STRONG SURFACE WEST TO NORTHWEST WINDS 25-40 KNOTS WILL BE THE MAIN HAZARD BEHIND THE FRONT FROM 18Z TO AROUND 06Z SUNDAY. THE STRONGEST WINDS ARE EXPECTED VICINITY AND NORTH OF INTERSTATE 90. WINDS WILL GRADUALLY DIMINISH IN MOST AREAS WITH SUNSET THROUGH THE EVENING...BECOMING LIGHTER IN MOST AREAS AFTER 06Z SUNDAY AS SURFACE HIGH PRESSURE BUILDS IN FROM THE WEST. && .FIRE WEATHER... A COLD FRONT AND ASSOCIATED UPPER LEVEL DISTURBANCE WILL BRING A COMBINATION OF GUSTY TO HIGH WIND...LOW RELATIVE HUMIDITY AND WARM TEMPERATURES. AS A RESULT EXPECT FIRE DANGER TO INCREASE ACROSS MANY AREAS WITH A LACK OF SNOW COVER. IN ZONES 283...281 AND 280 WHERE FUELS ARE CRITICAL THE RED FLAG WARNING WILL BE CONTINUED THROUGH THIS EVENING. FIRE CONDITIONS SHOULD IMPROVE SUNDAY AND MONDAY WITH COOLER TEMPERATURES AND LESS WIND. && .RIW WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING WYZ280-281-283. HIGH WIND WARNING FROM 3 PM THIS AFTERNOON TO MIDNIGHT MDT TONIGHT WYZ010-011. && SHORT TERM...HATTINGS LONG TERM...AR AVIATION...JB FIRE WEATHER...HATTINGS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE RIVERTON WY 400 AM MDT SAT MAR 28 2015 WYZ001>020-022>030-291200- 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- 400 AM MDT SAT MAR 28 2015 ...RED FLAG WARNING FOR PORTIONS OF CENTRAL WYOMING THIS AFTERNOON AND EVENING... ...HIGH WIND WARNING FOR THE LOWER ELEVATIONS OF JOHNSON COUNTY FOR LATE THIS AFTERNOON AND EVENING... THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL WYOMING. .DAY ONE...TODAY AND TONIGHT ELEVATED TO EXTREME FIRE WEATHER CONDITIONS EXPECTED WHERE FUELS ARE CRITICAL DUE TO WARM...DRY AND BREEZY CONDITIONS. PLEASE SEE FIRE WEATHER PRODUCTS FOR DETAILS. HIGH WINDS ARE LIKELY LOWER ELEVATIONS OF JOHNSON COUNTY LATE THIS AFTERNOON AND EVENING. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY TUESDAY...DRY...WINDY AND UNSEASONABLY WARM...WHICH WILL LEAD TO ELEVATED TO EXTREME FIRE WEATHER CONDITIONS LIKELY WHERE FUELS ARE CRITICAL. WEDNESDAY...COOLER WITH WINDY AREAS. ISOLATED THUNDERSTORMS OVER THE NORTH IN THE AFTERNOON. .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE URGED TO REPORT STRONG WINDS GUSTS. THANK YOU. TEAM RIVERTON
The national radar mosaic for the moment the first event began.
5 high wind. Local standard time, as filed.
Strong wind gusts occurred in a few locations across the Cody Foothills. The highest gusts were near Clark including a maximum of 84 mph.
A wind gust of 78 mph was reported at the wind sensor on the Chief Joseph Highway.
A mountain wave developed over the Wind River Range and brought high winds to the Lander foothills. The highest wind gust reported was 71 mph at the Lander airport. The wind tore the sheet metal off of an outbuilding in Lander.
A wind sensor along I-25 near Reno Hill north of Kaycee registered wind gusts around 60 mph with a peak of 62 mph.
A few wind gusts past 58 mph were reported at the Johnson County Airport in Buffalo, including a maximum gust of 60 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, March 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: 563516, 563514, 563517, 568063, 563512.