A strengthening pressure gradient produced strong southwest wind across central Wyoming. Peak winds occurred during the early morning with a gust to 61 mph near Casper.
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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.
A strengthening pressure gradient produced strong southwest wind across central Wyoming. Peak winds occurred during the early morning with a gust to 61 mph near Casper. Sustained wind of 40 to 45 mph and gusts near 70 mph occurred in the Green and Rattlesnake Mountains.
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 Jan 9, 3:37 PM MST, 6 hours 23 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RIVERTON WY 337 PM MST TUE JAN 9 2007 .SHORT TERM...TONIGHT THROUGH FRIDAY BIG CHANGE TO COLD AND SNOWY WEATHER IS WELL ON TRACK AND SHOULD ARRIVE ACROSS THE NORTH WEDNESDAY NIGHT AND IN THE SOUTH THURSDAY INTO THURSDAY EVENING. POTENTIAL FOR SIGNIFICANT SNOWFALL IS THERE FOR MUCH OF THE AREA. PLENTY OF DYNAMICS WITH THIS EXTENDED SNOW EVENT WITH ONLY THE COLD TEMPERATURES BEING A NEGATIVE. INITIAL BAROCLINIC BOUNDARY MOVES INTO THE WEST WEDNESDAY NIGHT WITH STEADY SNOW DEVELOPING ACROSS MUCH OF THE WEST...ESPECIALLY THE NORTHWEST. SNOW WILL ALSO DEVELOP BEHIND THE ARCTIC BOUNDARY ACROSS THE NORTH WEDNESDAY NIGHT AND THURSDAY. NAM12 SHOWS INCREASING MID LEVEL FRONTOGENESIS ALONG THE NORTHERN BORDER WITH INCREASING QG FORCING ACROSS THE NW AND NCNTRL SECTIONS. AS THE ARCTIC BOUNDARY PUSHES SOUTH THURSDAY MORNING INTO CENTRAL WYOMING...A JET STREAK INTERSECTS IT AND MAY SET THE STAGE FOR RAPID SNOW DEVELOPMENT ACROSS THE AREA FROM THE WIND RIVER MOUNTAINS EAST TO RIVERTON AND CASPER. AS THE UPPER LOW DIGS INTO NRN NV THURSDAY NIGHT... SIGNIFICANT QG FORCING IS NOTED ACROSS THE NORTH WITH IMPRESSIVE ISENTROPIC LIFT ACROSS VIRTUALLY THE ENTIRE AREA. STRONG UPSLOPE ALSO DEVELOPS EAST OF THE DIVIDE WITH NEARLY 30MB OF GRADIENT ACROSS THE STATE FROM NORTH TO SOUTH. ANOTHER JET STREAK ROTATES UP FROM THE SOUTH FRIDAY MORNING TO ENHANCE THE SNOWFALL ONCE AGAIN IN IN THE CENTRAL AND SOUTHERN ZONES. ISENTROPIC UPGLIDE GRADUALLY SHIFT EAST LATER FRIDAY MORNING AND AFTERNOON. THIS HAS ALL THE MAKINGS OF A LONG DURATION SNOW EVENT FOR QUITE A FEW AREAS. THE DETAILS ARE STILL UNCERTAIN ALONG WITH THE EXACT SNOWFALL AMOUNTS BUT IT IS QUITE LIKELY THAT SNOW ADVISORIES AND SOME WINTER STORM WATCHES WILL BE NEEDED BY TOMORROW. THE NEW 18Z GUIDANCE IS HITTING THE NORTH HARDER BUT THE DYNAMICS ARE IMPACTING THE ENTIRE AREA AT DIFFERENT TIMES THROUGHOUT THE EVENT. OTHER THAN THE MID LEVEL TEMPERATURES WHICH ARE TOO COLD FOR OPTIMUM SNOW GROWTH...THIS STORM LOOKS QUITE IMPRESSIVE. ONE OF THE HEAVIER SNOW AREAS STILL APPEARS TO BE SOUTH OF A LINE FROM RIVERTON TO CASPER AND POSSIBLY ACROSS PARTS OF THE NORTH AROUND THE CODY FOOTHILLS AND ABSAROKA MOUNTAINS. THE UPPER REACHES OF THE GREEN RIVER BASIN OR EAST SLOPE OF THE WYOMING RANGE COULD ALSO SEE SUSTAINED HEAVY SNOWFALL. HAVE HIT ALL AREAS WITH AT LEAST ADVISORY AMOUNTS WITH SOME WARNING CRITERIA IN MOST FAVORED AREAS. HIT THE FAVORED AREAS OF THE LOWER ELEVATIONS FROM RIVERTON TO CASPER AND POINTS SOUTH WITH 4 TO 8 INCHES FOR STARTERS WITH UP TO 10 INCHES NEAR THE MOUNTAINS. AMOUNTS AROUND A FOOT OR MORE IN THE NEARBY MOUNTAINS. HIT SOME OF THE WESTERN MOUNTAINS WITH A FOOT OR SO AND THE LOWER ELEVATIONS WITH ADVISORY AMOUNTS OF 3 TO 6 INCHES. DEPENDING OF THE EXACT EVOLUTION OF THIS STORM...AMOUNTS COULD BE SIGNIFICANTLY MORE IN A FEW SPOTS. TEMPERATURES WILL DROP SIGNIFICANTLY BEHIND THE FRONT WITH ONLY THE SNOW AND CLOUD COVER HOLDING TEMPERATURES UP SOMEWHAT THURSDAY NIGHT...BUT STILL VERY COLD. THE FIRST NIGHT OF THE EXTENDED PERIOD WILL LIKELY BE THE EXTREMELY BITTER COLD NIGHT. .LONG TERM...FRIDAY NIGHT THROUGH TUESDAY UPPER TROUGH TO IMPACT THE AREA THROUGH FRI NIGHT. TRACK AND SPEED OF THE SYSTEM STILL IN QUESTION. THE ONLY SURE THING IS THAT COLD AIR WILL BE ENTRENCHED OVER THE AREA. HAVE KEPT DECENT CHANCE OF SNOW OVER THE SOUTHERN HALF OF THE REGION WITH LESS CHANCE OF SNOW OVER THE NORTH ON FRIDAY. MAY NEED TO OVERHAUL FRI NIGHT FORECAST IF SYSTEM SLOWS DOWN MORE AND MOISTURE GETS ADVECTED OVER THE COLD AIR DOME. WILL SEE WHAT NEXT MODEL RUNS HAVE IN STORE. HAVE GONE WITH MAINLY DRY FORECAST SATURDAY AND QUITE COLD HIGHS. IT DOES APPEAR ANOTHER SURGE OF COLD AIR WILL DESCEND SOUTHWARD INTO WYOMING SUNDAY AFTERNOON INTO MONDAY MORNING. A CHANCE OF FLUFF SNOW FOR MANY PLACES WITH THIS SYSTEM. DID NOT WARM THINGS UP MUCH SUNDAY AND THEN SLIGHTLY COLDER ON MONDAY. SOME HOPE FOR MODERATION NEXT TUESDAY AS UPPER RIDGE MAY NUDGE COLD AIR EAST. HOWEVER THE NEWLY SNOW COVERED BASINS LIKELY TO BE STUCK IN AN INVERSION HINDERING THE WARMING. OTHER PLACES THAT MAY SEE SOME MIXING NEXT TUE WILL SEE MODERATION. && .RIW WATCHES/WARNINGS/ADVISORIES...HIGH WIND WARNING FOR ZONE 19... GREEN MOUNTAIN ZONE...FROM 10 PM THIS EVENING THROUGH 5 PM WEDNESDAY AND FOR ZONE 20...NATRONA COUNTY...FROM 3 AM TO 5 PM WEDNESDAY. && SHORT TERM...SKRBAC LONG TERM...RIW
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE RIVERTON WY 925 PM MST TUE JAN 9 2007 WYZ001>020-022>030-101201- 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- 925 PM MST TUE JAN 9 2007 ...HIGH WIND WARNING FOR THE GREEN MOUNTAINS REGION FROM 10 PM MST THIS EVENING THROUGH 5 PM MST WEDNESDAY... ...HIGH WIND WARNING FOR NATRONA COUNTY FROM 3 AM MST WEDNESDAY THROUGH 5 PM MST WEDNESDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL WYOMING. .DAY ONE...TONIGHT HIGH WINDS ARE LIKELY BETWEEN BEAVER RIM...SWEETWATER STATION... JEFFREY CITY AND MUDDY GAP THROUGH WEDNESDAY AND MAY DEVELOP AROUND CASPER BY WEDNESDAY MORNING. SOUTHWEST WINDS OF 35 TO 45 MPH WITH GUSTS TO 65 MPH ARE EXPECTED TO DEVELOP THIS EVENING OVER THE GREEN MOUNTAINS AREA AND WILL SPREAD INTO CASPER BY MORNING. THESE WINDS WILL MAKE TRAVEL DIFFICULT...ESPECIALLY FOR THOSE IN HIGH PROFILE AND LIGHT WEIGHT VEHICLES. STRONG WINDS ARE ALSO EXPECTED AROUND THE CODY FOOTHILLS AND SURROUNDING MOUNTAINS...UPPER WIND RIVER BASIN...SOUTH PASS...AND OTHER SUMMIT LOCATIONS OF THE WESTERN MOUNTAINS. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY THE HIGH WINDS WILL CONTINUE THROUGH WEDNESDAY AFTERNOON BETWEEN BEAVER RIM AND CASPER. THEY WILL BEGIN TO TAPER OFF AS A COLD FRONT APPROACHES. A MAJOR WINTER STORM SYSTEM IS TAKING SHAPE FOR CENTRAL AND WESTERN WYOMING FROM WEDNESDAY NIGHT THROUGH FRIDAY. A VERY COLD ARCTIC AIRMASS WILL PUSH SOUTH ACROSS NORTHERN WYOMING WEDNESDAY EVENING AND ACROSS CENTRAL AND SOUTHERN WYOMING EARLY THURSDAY MORNING. THIS FRONT WILL SPREAD SNOW ACROSS MOST OF WEST AND CENTRAL WYOMING...WITH SNOW INITIALLY FALLING ON WARM ROAD SURFACES OVERNIGHT WEDNESDAY ACROSS CENTRAL WYOMING...RESULTING IN ROADS AND HIGHWAYS BECOMING ICY AND EXTREMELY SLICK...ESPECIALLY DURING MORNING COMMUTE TIME THURSDAY MORNING. AREAS OF HEAVIEST SNOWFALL STILL REMAIN UNCERTAIN BUT LOWER ELEVATIONS ARE GENERALLY EXPECTED TO RECEIVE 3 TO 6 INCHES OF SNOWFALL BY FRIDAY MORNING WITH 6 TO 12 INCHES IN THE MOUNTAINS. A FEW AREAS COULD EVEN SEE SNOWFALL INTO THE WEEKEND AS SEVERAL WEATHER DISTURBANCES MOVE DOWN FROM THE NORTH. STRONG NORTHEAST WINDS WILL DEVELOP BEHIND THIS COLD FRONT... ESPECIALLY OVER SOUTH PASS...THE RED DESERT...INTERSTATE 80 CORRIDOR AND ACROSS THE SOUTHWEST CORNER OF WYOMING. THESE STRONG NORTHEAST WINDS COMBINED WITH SNOWFALL MAY MAKE TRAVEL TREACHEROUS THURSDAY AND INTO FRIDAY. WELL BELOW AVERAGE TEMPERATURES WILL OCCUR FRIDAY THROUGH THE WEEKEND AS THE ARCTIC AIR BECOMES ENTRENCHED OVER THE REGION. OVERNIGHT LOWS WILL LIKELY PLUMMET WELL BELOW ZERO IN MANY LOCALES SATURDAY AND SUNDAY MORNINGS. EVEN NEXT MONDAY LOOKS TO BE QUITE COLD NOW. OVERNIGHT LOWS SATURDAY AND SUNDAY MORNING WILL LIKELY RANGE FROM -10 TO -20 BELOW ZERO IN THE EAST AND MOUNTAIN LOCATIONS WITH -25 TO -35 BELOW ZERO ACROSS THE FAR WEST VALLEYS AND BASINS. SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT ANY SUSTAINED WIND SPEEDS OVER 40 MPH OR WIND GUSTS OVER 60 MPH. SKRBAC
The national radar mosaic for the moment the first event began.
2 high wind. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2007Every state in 2007This day in weather historyWarnings in Wyoming, January 2007
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: 4502, 4503.