A strong southwest flow brought high wind to the Casper area. Wind gusts as high as 62 mph were recorded at Casper/Natrona County International Airport.
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The episode as NWS RIW wrote it up.
A strong southwest flow brought high wind to the Casper area. Wind gusts as high as 62 mph were recorded at Casper/Natrona County International Airport.
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 19, 2:19 AM MST, 10 hours 30 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RIVERTON WY 319 AM MDT SAT MAR 19 2011 .SHORT TERM...TODAY THROUGH MONDAY NIGHT SOUTHWEST FLOW INCREASING OVER WYOMING AS THE UPPER LOW CONTINUES TO SPIN OFF THE PAC NW COAST. SW-NE ORIENTED 100KT JET TO MOVE INTO WESTERN WYOMING AND EASTERN IDAHO THIS MORNING...SLOWLY DRIFTING EAST INTO CENTRAL WYOMING THIS AFTERNOON. THIS WILL BRING WINDY TO VERY WINDY CONDITIONS TO MUCH OF THE CWA THROUGH TONIGHT. THE STRONGEST WINDS SHOULD BE OVER THE SOUTHEAST WIND RIVERS...SOUTHEAST FREMONT AND NATRONA COUNTIES AND INTO THE SOUTHERN AND EASTERN BIGHORN MOUNTAINS. SHOULD NOT SEE HIGH WINDS WITH THIS EVENT. SHORTWAVE WILL MOVE INTO THE WEST THIS AFTERNOON AND EVENING BRINGING A QUICK ROUND OF LIGHT SNOW WITH A COUPLE INCHES POSSIBLE IN THE MOUNTAINS. LOOKS TO BE POSSIBLY MIXED WITH RAIN IN THE VALLEYS WITH MILD TEMPERATURES EXPECTED. LI'S LOOK TO BE NEGATIVE THIS AFTERNOON SO HAVE INCLUDED ISOLATED THUNDERSTORMS. RIDGE BUILDS IN BEHIND THIS EVENING'S SHORTWAVE. WINDS WILL ON THE INCREASE AGAIN BY SUNDAY AFTERNOON AS THE RIDGE AXIS APPROACHES AND MOVES THROUGH WITH A INCREASING SOUTHWEST FLOW ALOFT. A STRONGER JET MOVES INTO THE SOUTHERN GREAT BASIN SUNDAY NIGHT...MOVING INTO UTAH BY 12Z MONDAY MORNING. SEVERAL WEAK/FRAGMENTED SHORTWAVES IN THE SOUTHWEST FLOW WILL BRING A CHANCE OF SNOW/VALLEY RAIN/SNOW TO THE WEST SUNDAY AND SUNDAY NIGHT. LITTLE ACCUMULATION IS EXPECTED. THE FLOW BACKS TO THE SOUTH MONDAY MORNING AS THE UPPER LOW OPENS UP AND SWINGS ONSHORE. MAIN PORTION OF THE LOW MOVES ACROSS THE SOUTHWEST MONDAY MORNING...THEN LIFTS INTO UTAH AND NEVADA BY LATE MONDAY AFTERNOON. THE NOW NEGATIVELY TILTED TROUGH LIFTS NORTHEAST ACROSS IDAHO AND WYOMING MONDAY NIGHT. THIS WILL BRING A PERIOD OF SNOW TO THE WEST...WITH A CHANCE OF RAIN/SNOW TO AREAS EAST OF THE DIVIDE MONDAY NIGHT. .LONG TERM...TUESDAY THROUGH SATURDAY TUESDAY LOOKS UNSETTLED WITH A CHANCE OF RAIN AND SNOW AT THE LOWER ELEVATIONS OF THE NORTH WITH A LESSER CHANCE CENTRAL AND SOUTH. SOME SNOW IN THE MOUNTAINS TUESDAY. BRISK WIND AND COLDER TUE AS WELL. LINGERING PRECIP OVER THE NORTH ZONES TUE NIGHT DECREASING AFTER MIDNIGHT. MOSTLY DRY ELSEWHERE. WEDNESDAY STILL SEEMS DRY FOR MOST PLACES. A WEAK WEATHER SYSTEM PASSES THROUGH THE REGION WED NIGHT WITH A CHANCE OF PRECIP IN THE WEST AND SOUTH. THE CENTRAL AND NORTH LOOK TO BE DRY. THURSDAY LOOKS TO BE DRY CENTRAL AND EAST WITH A LOW CHANCE OF PRECIP IN THE WEST AND SOUTH DUE TO MOISTURE IN THE FLOW. THE NEXT WEATHER SYSTEM MOVES INTO THE WESTERN U.S. FRIDAY WITH MOISTURE MOVING INTO WESTERN WY FRI PM INTO FRI NIGHT. PRECIP SHOULD CROSS THE DIVIDE AFTER MIDNIGHT FRIDAY NIGHT. SATURDAY WILL BE UNSETTLED WITH A CHANCE OF RAIN AND SNOW FOR MOST PLACES. TEMPERATURES WILL BE COOLER TUE AND WED. THEN A LITTLE WARMER THURS AND FRI. BACK TO COLDER ON SATURDAY. && .AVIATION... VFR CONDITIONS WILL PREVAIL THROUGH THE MORNING WITH SOME DIFFUSE DUST CARRIED UP FROM THE DESERT SOUTHWEST ACROSS THE REGION. MOST OF WYOMING WILL BE IN A WARM SECTOR THIS AFTERNOON AS SURFACE LOW PRESSURE DEEPENS OVER SOUTH CENTRAL MONTANA. THIS SETUP WILL BRING GUSTY SOUTH WIND AT 20-30KT ACROSS MUCH OF THE AREA 20Z SAT-01Z SUN. A DISTURBANCE WILL LIFT ACROSS WESTERN WYOMING INTO SOUTHWEST MONTANA IN THE AFTERNOON AND SPREAD NUMEROUS -SHSN OVER THE WESTERN MOUNTAINS WITH FREQUENT OBSCURATIONS. SHSN WILL INCREASE VCNTY KAFO-KJAC IN THE AFTERNOON WITH MVFR/IFR CONDITIONS PREVAILING AFTER 02Z SUNDAY. SCT SHSN WITH ACCOMPANYING MVFR/IFR CONDITIONS WILL ALSO DEVELOP VCNTY KBPI-KPNA AFTER 02Z SUN. && .FIRE WEATHER... VERY WINDY CONDITIONS EXPECTED ACROSS THE DISTRICT TODAY WITH RH'S IN THE TEENS AND 20S EAST OF THE DIVIDE. THE WINDS WILL CONTINUE THIS EVENING...TAPERING OVERNIGHT. ISOLATED THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON. A WEAK DISTURBANCE WILL BRING LIGHT MOUNTAIN SNOW AND VALLEY RAIN/SNOW TO THE WEST THIS AFTERNOON AND EVENING. ANOTHER DISTURBANCE BRINGS ANOTHER CHANCE OF SNOW TO THE WEST SUNDAY AFTERNOON AND EVENING. WINDS WILL ALSO INCREASE SUNDAY AFTERNOON AND EVENING. A MORE SIGNIFICANT TROUGH WILL MOVE THROUGH MONDAY NIGHT...BRINGING WIDESPREAD SNOW TO THE WEST AND POSSIBLY TO AREAS EAST OF THE DIVIDE. && .RIW WATCHES/WARNINGS/ADVISORIES...NONE. && SHORT TERM...TWB LONG TERM...AR AVIATION...AEM FIRE WEATHER...TWB
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE RIVERTON WY 500 AM MDT SAT MAR 19 2011 WYZ001>020-022>030-201200- 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 SAT MAR 19 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL WYOMING. .DAY ONE...TODAY AND TONIGHT ISOLATED THUNDERSTORMS ARE POSSIBLE IN THE WEST THIS AFTERNOON. LIGHTNING WILL BE THE PRIMARY THREAT. SOME BRIEF HEAVY SNOWFALL IS LIKELY WITH ANY THUNDERSTORMS. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY A STORM SYSTEM WILL BRING A CHANCE OF RAIN AND SNOW...WITH SNOW FOR THE MOUNTAINS MONDAY NIGHT AND TUESDAY. THOSE WITH TRAVEL PLANS WILL WANT TO STAY UPDATED ON THIS STORM AND ITS POTENTIAL FOR SIGNIFICANT SNOWFALL IN SOME LOCATIONS. .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ASKED TO REPORT ANY LIGHTNING TODAY. THANK YOU. TEAM RIVERTON
The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2011Every state in 2011This day in weather historyWarnings in Wyoming, March 2011
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: 278848.