A tight surface pressure gradient and stable conditions in the lower atmosphere created strong winds in the favored gap wind areas.
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The episode as NWS CYS wrote it up.
A tight surface pressure gradient and stable conditions in the lower atmosphere created strong winds in the favored gap wind areas.
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 Cheyenne, WY wrote its last area forecast discussion before the first event at Jan 26, 3:12 PM MST, 58 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHEYENNE WY 312 PM MST WED JAN 26 2011 .SHORT TERM...TONIGHT THROUGH FRIDAY MAIN CONCERN THIS PERIOD IS THE LIKELIHOOD OF HIGH WINDS AT ARLINGTON AND BORDEAUX TONIGHT INTO THURSDAY AND THURSDAY NIGHT INTO FRIDAY. MODELS ARE INDICATING 30 TO 45 KNOT WINDS AT 700MB...IN COMBINATION WITH A STRONG PRESSURE GRADIENT SETTING UP AS A SURFACE HIGH PRESSURE MOVES EASTWARD FROM IDAHO AND A SURFACE LOW PRESSURE MOVES SOUTHWARD INTO THE DAKOTAS. BELIEVE WINDS WILL BE STRONG AND GUSTY BOTH NIGHTS...BUT AM NOT CONFIDENT ENOUGH THAT THE WINDS WILL REACH HIGH WIND CRITERIA TO ISSUE A HIGH WIND WARNING FOR EITHER NIGHT. IF THE WINDS DO REACH CRITERIA IT WILL MOST LIKELY BE DUE TO THE SUSTAINED WINDS. A PEAK GUST OF CLOSE TO 60 MPH CANNOT BE RULED OUT FOR EITHER NIGHT...BUT BELIEVE IT WILL AN ISOLATED OCCURRENCE. BORDEAUX LOOKS TO HAVE THE STRONGEST WINDS...BUT ARLINGTON MAY HAVE NEAR EQUAL WINDS DUE TO THE STRONG SURFACE PRESSURE GRADIENT. OTHERWISE PRECIP. CHANCES WILL BE ZERO TO SLIGHT FOR THE AREA. THE 300 MB JET WILL MOVE TO THE NORTHEAST OF THE AREA THROUGH THE PERIOD...WITH A JET STREAM MOVING BY ON FRIDAY. THE AREA IS IN A FAVORABLE LOCATION OF ASCENT FROM THE JET STREAK...BUT THE ENVIRONMENT IS LACKING IN MOISTURE. ONLY CHANCES FOR PRECIP TO DEVELOP ARE DURING THE REST OF THE AFTERNOON OVER THE SNOWY AND SIERRA MTNS. PRECIP CHANCES AGAIN FOR THE SIERRA AND SNOWY MTNS EARLY FRIDAY MORNING AS SOME WEAK ISENTROPIC LIFT DEVELOPS FOR THAT LOCALE. .LONG TERM...FRIDAY NIGHT THROUGH NEXT WEDNESDAY...MODELS IN REASONABLE AGREEMENT THROUGH NEXT WEEKEND...BUT THEN SOLUTIONS DIVERGE SIGNIFICANTLY BY EARLY NEXT WEEK. ALL MODELS SHOW MAINLY ZONAL FLOW ALOFT THROUGH SATURDAY NIGHT AS THE UPPER LEVEL RIDGE WEST OF THE AREA STARTS TO WEAKEN. TEMPS WILL BE ABOVE NORMAL INTO SATURDAY WITH HIGHS POSSIBLY NEAR 50 ACROSS THE HIGH PLAINS WITH 30S AND 40S ELSEWHERE. MAINLY DRY WEATHER EXPECTED TO LAST INTO SATURDAY NIGHT BEFORE A PACIFIC STORM SYSTEM PUSHES ONSHORE ALONG THE WEST COAST. WILL NEED TO KEEP AN EYE ON THIS STORM AS CURRENT MODEL RUNS SHOW THIS UPPER LEVEL TROUGH NEARLY BECOMING A CLOSED LOW SOUTH OF WYOMING NEAR THE FOUR CORNERS REGION AS AN ARCTIC AIRMASS QUICKLY PUSHES SOUTHWARD ALONG THE NRN ROCKIES. ALTHOUGH MODELS SHOW ONLY LIGHT TO MODERATE PRECIP IN THE AREA...THIS MAY CHANGE OVER THE NEXT FEW DAYS. INCREASED POP FOR ACCUMULATING SNOW SUNDAY THROUGH MONDAY OVER THE ENTIRE AREA WITH PROBABILITIES UP TO 35 PERCENT IN THE LOWER ELEVATIONS AND 60 PERCENT IN THE MOUNTAINS. MUCH COLDER AIR IS EXPECTED TO MOVE INTO SOUTHEAST WYOMING AND WESTERN NEBRASKA BY LATE SUNDAY AND MONDAY. BUT MODELS ARE NOT IN GOOD AGREEMENT WITH HOW COLD IT WILL GET. THE 12Z ECMWF SHOWING THE BASE OF THE ARCTIC TROUGH OVER MOST OF THE GREAT PLAINS STATES WITH 700MB TEMPS LOWERING TO -20 TO -25 DEGS...AND 850MB TEMPS NEAR -20...WHICH HINTS TO HIGHS AROUND ZERO. THE REST OF THE MODELS INCLUDING THE GEM...GFS...AND ENSEMBLES SHOW THE COLDEST AIR MUCH FURTHER EAST WITH NEAR OR SLIGHTLY BELOW NORMAL TEMPS ACROSS THE REGION INTO TUESDAY AND WEDNESDAY. THE 12Z GFS IS COLDER THAN THE GEM AND DGEX BUT NOT QUITE AS COLD AS THE ECMWF. TRENDED TOWARDS THE ECMWF AND GFE ENSEMBLE...BUT DID NOT KEEP THE COLD AIR AROUND AS LONG IN THE EXTENDED. KEPT THE FORECAST MAINLY DRY AFTER MONDAY WITH ANY CHANCE OF SNOW MAINLY OVER THE MOUNTAINS. CONTINUED TO LOWER MIN AND MAX TEMPS FROM SUNDAY NIGHT THROUGH WEDNESDAY. && .AVIATION...18Z TAF ISSUANCE. VFR CONDITIONS ARE EXPECTED OVER THE AREA WITH MVFR CIGS POSSIBLE AT KRWL UNTIL THE MIDDLE OF THIS AFTERNOON. WEST TO NORTHWEST WINDS GENERALLY BE RELATIVELY LIGHT BETWEEN 10 TO 15 KTS WITH OCCASIONAL GUSTS UP TO 30 KTS POSSIBLE OVER WYOMING. && .FIRE WEATHER...DESPITE THE RATHER DRY ENVIRONMENT...RH VALUES WILL BE WELL ABOVE CRITICAL LEVELS. THE ONLY CONCERN WILL BE THE GUSTY WINDS FOR THE ARLINGTON AND BORDEAUX AREAS THROUGH THE OVERNIGHT AND MORNING HOURS THURSDAY AND FRIDAY. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && SHORT TERM/FIRE WEATHER...LUNDQUIST LONG TERM/AVIATION...TJT
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHEYENNE WY 1159 AM MST WED JAN 26 2011 NEZ002-003-019>021-054-055-095-096-WYZ101>119-271900- DAWES-BOX BUTTE-SCOTTS BLUFF-BANNER-MORRILL-KIMBALL-CHEYENNE- NORTH SIOUX-SOUTH SIOUX-CONVERSE COUNTY LOWER ELEVATIONS- NIOBRARA COUNTY-NORTH LARAMIE RANGE- FERRIS/SEMINOE/SHIRLEY MOUNTAINS-SHIRLEY BASIN- CENTRAL LARAMIE RANGE AND SOUTHWEST PLATTE COUNTY- EAST PLATTE COUNTY-GOSHEN COUNTY-CENTRAL CARBON COUNTY- NORTH SNOWY RANGE FOOTHILLS-SOUTHWEST CARBON COUNTY- SIERRA MADRE RANGE-UPPER NORTH PLATTE RIVER BASIN-SNOWY RANGE- LARAMIE VALLEY-SOUTH LARAMIE RANGE-SOUTH LARAMIE RANGE FOOTHILLS- CENTRAL LARAMIE COUNTY-EAST LARAMIE COUNTY- 1159 AM MST WED JAN 26 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE WESTERN NEBRASKA PANHANDLE...EAST CENTRAL WYOMING...SOUTH CENTRAL WYOMING AND SOUTHEAST WYOMING. .DAY ONE...THIS AFTERNOON AND TONIGHT GUSTY WINDS WILL DEVELOP OVER THE ARLINGTON AND BORDEAUX AREAS AROUND SUNSET AND LAST THROUGH THE OVERNIGHT HOURS. WINDS WILL RANGE FROM 30 TO 40 MPH...WITH GUSTS UP TO 55 MPH POSSIBLE. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY THE GUSTY WINDS WILL CONTINUE FOR THE ARLINGTON AND BORDEAUX AREAS THROUGH NOON THURSDAY BEFORE DECREASING. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY AND TONIGHT. && THIS PRODUCT...ALONG WITH OTHER WEATHER...HYDROLOGIC...AND CLIMATE INFORMATION IS AVAILABLE ON THE WEB AT... HTTP://WEATHER.GOV/CHEYENNE LUNDQUIST
The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
WYDOT at Bordeaux recorded sustained winds in excess of 40 mph with peak gusts of 58 mph from 26/1630 to 26/1655 MST.
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, January 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: 269509.