An unseasonably strong low pressure system brought high winds to Natrona County and southeast Fremont County. In and around Casper, wind gusts around 60 mph were common.
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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.
An unseasonably strong low pressure system brought high winds to Natrona County and southeast Fremont County. In and around Casper, wind gusts around 60 mph were common. The wind caused multiple reports of downed power lines and subsequent outages. Widespread wind damage was also reported in the Cody area along the east slopes of the Absaroka Range. The strong wind downed at least 30 trees around Cody, many of which were located on the grounds of the Buffalo Bill Historical Center and the Riverside Cemetery. A billboard along highway 120 north of Cody was also toppled by the wind.
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 Jun 17, 2:29 AM MST, 3 hours 1 minute earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RIVERTON WY 329 AM MDT THU JUN 17 2010 .SHORT TERM...TODAY THROUGH SATURDAY NIGHT THE VIGOROUS NEGATIVELY TILTED SHORTWAVE IS PRESENTLY TRACKING EAST NORTHEAST ACROSS WYOMING. OUT AHEAD OF THE TROUGH AXIS A NARROW BAND OF CONVECTION FORMED ON THE EASTERN LEADING EDGE OF A WIDE AREA OF RAPIDLY MOVING NORTHBOUND SHOWERS ACROSS WESTERN AND CENTRAL WYOMING. A STRONG AREA OF Q VECTOR FORCING WITH A MAGNITUDE OF -40K/M^2/1E16S IS EXPECTED TO SWEEP ACROSS WESTERN AND CENTRAL WYOMING THIS MORNING. WITH THE HELP OF A STRONG WEST SOUTHWEST FLOW...THE AFOREMENTIONED FORCING WILL KEEP OCCASIONAL RAIN TURING TO SNOWFALL GOING WEST OF THE DIVIDE AFTER THE SHOWERS END EAST OF THE DIVIDE...ESPECIALLY IN NORTHWEST WY...NAMELY YNP...WHERE THE HEAVIEST PRECIP IS EXPECTED. H7 TEMPS OF -7 ARE STILL EXPECTED ACROSS WESTERN WY BY 12Z THIS MORNING. THE GFS APPEARS TO BE ON TRACK AS FAR AS THE COOLING GOES AT H7 BASED ON AREA MTN TEMPS AT THAT LEVEL. ISSUED A WINTER WEATHER ADVISORY FOR THE PARK FOR 3 TO 6 INCHES OF SNOWFALL THROUGH THIS MORNING. WITH THE HIGH VOLUME OF VISITORS THIS TIME OF YEAR...FELT AN ADVISORY WAS WARRANTED DESPITE THE LOW END AMOUNTS. OTHER MOUNTAIN ZONES SUCH AS THE WIND RIVER MTNS...TETONS...AND THE SALT RIVER RANGE WILL HAVE SIMILAR AMOUNTS BUT AT HIGHER ELEVATIONS OF AROUND 9000 FEET. SNOW WILL HOWEVER FALL AS LOW AS 6500 FEET. SKIES WILL CLEAR LATER TODAY AS SUBSIDENCE MOVES IN AND THE FLOW BECOMES MORE CONFLUENT. HOWEVER...NUMEROUS RAIN AND SNOW SHOWERS WILL CONTINUE IN NORTHWEST WY AS WELL AS IN THE BIG HORN MTNS AS WEST SOUTHWEST UPSLOPE FLOW CONTINUES. TEMPS WILL BE COOLER EVERYWHERE TODAY BEHIND YESTERDAYS PACIFIC COLD FRONT. THE HIGH WIND WARNING IS CURRENTLY IN EFFECT FOR THE SOUTHERN WIND CORRIDOR FOR TODAY. THE GRADIENT WILL CONTINUE TO TIGHTEN AT ALL LEVELS BEHIND THE TROUGHPA WITH INCREASING WEST WINDS. WILL BE EXTENDING THE WARNING THROUGH 21Z THIS AFTERNOON. THE GRADIENT WILL BEGIN TO RELAX BY 00Z FRIDAY. A RIDGE WILL BUILD INTO THE AREA FRIDAY WITH H7 TEMPS REBOUNDING TO 13C IN SOUTHERN WY. HIGH TEMPS WILL RECOVER TO WEDNESDAYS HIGHS. YET ANOTHER CLOSED LOW WILL BECOME ESTABLISHED OVER OREGON THIS WEEKEND WITH A SOUTHWEST FLOW INCREASING OUT AHEAD OF IT OVER WY. THIS WILL RESULT IN SCATTERED TSRA OVER NW WY BY LATE SATURDAY AND SAT NIGHT AS MOISTURE STREAMS IN FROM SOUTHWEST STEERING WINDS. .LONG TERM...SUNDAY THROUGH THURSDAY MORE SUMMER-LIKE PATTERN EVOLVES NEXT WEEK WITH NEAR OR SLIGHTLY ABOVE NORMAL TEMPERATURES AND CHANCES OF LATE DAY THUNDERSTORMS MAINLY ACROSS THE NORTHERN THIRD OF WYOMING THROUGH THIS PERIOD. MEDIUM-RANGE DETERMINISTIC MODELS EACH SHOWING FAIRLY GOOD RUN-TO-RUN CONSISTENCY...SIMILAR DISCREPANCIES BETWEEN MODELS THIS MORNING. LONGWAVE PATTERN WITH SUB-TROPICAL RIDGE OF HIGH PRESSURE OVER THE SOUTHEAST U.S. AND TROUGH OVER THE WESTERN U.S PERSISTS THROUGHOUT NEXT WEEK. ECMWF CONTINUES TO EXPAND RIDGE INTO THE CENTRAL PLAINS BY WEDNESDAY WHILE GFS KEEPS A MORE PROGRESSIVE ZONAL FLOW ACROSS THE NORTHERN TIER OF THE U.S. BEFOREHAND...MAIN DIFFERENCES ARE WITH INDIVIDUAL SHORTWAVES IN SOUTHWEST FLOW THAT THAT WILL MAINLY HAVE TO BE DEALT WITH IN THE SHORT-TERM. MEAN QUASI-STATIONARY FRONT WILL BE POSITIONED NEAR THE MONTANA WYOMING BORDER WITH BEST MOISTURE AND INSTABILITY ALONG AND NORTH OF THIS FRONT. MOST OF CENTRAL AND SOUTHERN WYOMING WILL BE IN WARM SECTOR WITH SOUTHWEST FLOW...MEAN H7 TEMPERATURES 12-14C AND HIGHS 80 TO 85 AT 5KFT WITH MOSTLY 70S IN THE WESTERN VALLEYS. TEMPERATURES ON NORTH SIDE OF THE FRONT WILL BE 5 TO 10F COOLER ON AVERAGE. FORECAST WEIGHTED TOWARD PERSISTENCE OF LARGE-SCALE PATTERN...MOSTLY DISCOUNTING THE CHANGES ADVERTISED BY ECMWF AND ITS RETROGRADING RIDGE AND WARMER DRIER PATTERN...AND GFS WITH ITS FLATTER COOLER ZONAL FLOW WITH MORE MOISTURE AND INSTABILITY FURTHER SOUTH ACROSS WYOMING. && .AVIATION... STRONG SOUTHWEST TO WEST WINDS WILL BE ON THE INCREASE THIS MORNING BETWEEN KRKS AND KCPR WITH SPEEDS OF AROUND 40G60KTS. THESE WINDS WILL PERSIST THROUGH THE AFTERNOON...BEGINNING TO DIMINISH IN THE LATE AFTERNOON AND EVENING. MOST AREAS TODAY WILL BE QUITE WINDY AS WELL WITH THE WINDS PERSISTING THROUGH THE EARLY EVENING. SOME SNOW IS EXPECTED OVER THE MOUNTAINS OF WESTERN WYOMING...ESPECIALLY IN THE TETONS AND YELLOWSTONE PARK. SOME OF THE SNOW MAY MOVE INTO KJAC OR KAFO...BUT THE IMPACT WILL BE LIMITED. THE SKY WILL CLEAR OVERNIGHT. && .FIRE WEATHER... SNOW WILL FALL IN WESTERN WYOMING WITH 3 TO 6 INCHES OF SNOWFALL EXPECTED OVER SOME OF THE HIGHER COUNTRY THIS MORNING. OTHERWISE EXPECT DRY WEATHER TODAY WITH NUMEROUS RAIN AND SNOW SHOWERS CONTINUING IN NORTHWEST WYOMING AND IN THE BIG HORN MOUNTAINS THIS AFTERNOON. STRONG WEST SOUTHWEST WINDS WILL TAKE PLACE FROM EASTERN SWEETWATER COUNTY TO CASPER TODAY. THE VIGOROUS STORM CENTER WILL EXIT TO THE EAST OF THE AREA THIS EVENING TAKING ITS PRECIPITATION AND WIND WITH IT. HIGH PRESSURE WILL BRING WARMER AND DRIER AIR TO THE REGION FRIDAY AND THROUGH THE WEEKEND. && .RIW WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL NOON MDT TODAY WYZ019-020-030. FLOOD WATCH THROUGH SATURDAY AFTERNOON WYZ017-018. FLOOD WATCH THROUGH THIS AFTERNOON WYZ028. WINTER WEATHER ADVISORY UNTIL NOON MDT TODAY WYZ001. && SHORT TERM...LIPSON LONG TERM...AEM AVIATION...TWB FIRE WEATHER...LIPSON
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE RIVERTON WY 500 AM MDT THU JUN 17 2010 WYZ001>020-022>030-181100- 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- 500 AM MDT THU JUN 17 2010 ...FLOOD WATCH FOR THE BLACKS FORK RIVER FROM GRANGER TO LITTLE AMERICA IN WESTERN SWEETWATER COUNTY THROUGH THIS AFTERNOON... ...FLOOD WATCH FOR THE LITTLE POPO AGIE RIVER...THE MIDDLE FORK POPO AGIE RIVER...AND ALL FORKS OF THE LITTLE WIND RIVER THROUGH SATURDAY AFTERNOON... ...HIGH WIND WARNING FOR PORTIONS OF SOUTHERN AND CENTRAL WYOMING FOR THIS MORNING... ...WINTER WEATHER ADVISORY FOR YELLOWSTONE PARK THROUGH THIS MORNING... THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL WYOMING. .DAY ONE...TODAY AND TONIGHT MINOR FLOODING IS EXPECTED TO CONTINUE ALONG THE BLACKS FORK RIVER BETWEEN GRANGER AND LITTLE AMERICA THROUGH THIS EVENING. WARMER TEMPERATURES AND GUSTY WINDS WEDNESDAY LED TO ANOTHER ROUND OF SIGNIFICANT MELTING OF THE NEW SNOWFALL IN THE WIND RIVER MOUNTAINS. THIS WILL LEAD TO RISES IN AREA RIVERS AND CREEKS...WHICH MAY LEAD TO MORE FLOODING TODAY. SEE FLOOD WATCH PRODUCTS FOR MORE INFORMATION. OTHERWISE...THE MAJORITY OF STREAMS AND RIVERS WILL REMAIN FAIRLY HIGH AND SWIFT ACROSS THE AREA AS SEASONAL SNOWMELT CONTINUES. STRONG WEST SOUTHWEST WINDS WILL BLOW OVER EASTERN SWEETWATER COUNTY THROUGH NATRONA COUNTY THIS MORNING. WIND SPEEDS OF 35 TO 45 MPH WITH GUSTS TO 65 MPH WILL BE POSSIBLE. HIGH WIND WARNINGS ARE IN EFFECT FOR THESE AREAS. SEE HIGH WIND WARNING PRODUCTS FOR MORE INFORMATION. 3 TO 6 INCHES OF SNOW IS EXPECTED IN YELLOWSTONE PARK THROUGH THIS MORNING. A WINTER WEATHER ADVISORY IS IN EFFECT FOR THE PARK. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY TUESDAY A SLIGHT CHANCE OF THUNDERSTORMS WILL BE FOUND MAINLY ACROSS THE NORTHERN THIRD OF WYOMING THROUGH THIS PERIOD. .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT ANY STREAMS OR RIVERS RISING RAPIDLY...NEAR BANKFULL OR WHERE FLOODING IS OCCURRING. SPOTTERS ARE ALSO ENCOURAGED TO REPORT ANY SNOWFALL AMOUNTS. THANK YOU. TEAM RIVERTON
The national radar mosaic for the moment the first event began.
3 high wind. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2010Every state in 2010This day in weather historyWarnings in Wyoming, June 2010
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: 241218, 241221, 241219.