Gusty westerly winds over the south Laramie Range and adjacent foothills were the result of a strong surface pressure gradient.
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The episode as NWS CYS wrote it up.
Gusty westerly winds over the south Laramie Range and adjacent foothills were the result of a strong surface pressure gradient.
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 Mar 23, 2:41 AM MST, 1 hour 14 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHEYENNE WY 341 AM MDT WED MAR 23 2011 .SHORT TERM...TODAY THROUGH THURSDAY NIGHT...CURRENT OBS ACROSS SOUTHEAST WYOMING SHOW WINDS SLOWLY SUBSIDING AS THE LOW PRESSURE SYSTEM OVER THE NORTHERN GREAT PLAINS PUSHES EASTWARD INTO THE GREAT LAKES REGION EARLY THIS MORNING. WILL ALLOW THE HIGH WIND WARNING FOR PORTIONS OF THE SOUTHERN LARAMIE RANGE AND NORTHERN SNOWY RANGE FOOTHILLS TO EXPIRE AT 4 AM WITH WINDS IN THOSE LOCATIONS LOWERING BELOW CRITERIA IN THE LAST FEW HOURS. WRAP AROUND LIGHT SNOW SHOWERS NORTH OF I80 FROM DOUGLAS...EASTWARD TO LUSK AND TORRINGTON ARE DISSIPATING EARLY THIS MORNING. SNOW ACCUMULATIONS HAVE BEEN LIGHT AND GENERALLY A DUSTING ON GRASSY AND ELEVATED SURFACES. ALTHOUGH WINDS WILL GENERALLY TREND LOWER THROUGH THE DAY ACROSS MOST OF THE AREA...MOS GUIDANCE AND MODEL SOUNDINGS SHOW A BRIEF INCREASE IN NORTHWEST WINDS LATE THIS MORNING AND INTO EARLY THIS AFTERNOON AS BOUNDARY LAYER MIXING WILL RESULT IN WINDS ALOFT TRANSLATING TO THE SURFACE. CURRENT MODELS SHOW 700MB WINDS BETWEEN 35 TO 40 KTS FOR A TIME THIS MORNING...SO MAY SEE A BRIEF PERIOD OF SUSTAINED WINDS AROUND 30 MPH WITH GUSTS UP TO 45 MPH FROM KIMBALL AND SIDNEY NORTHEASTWARD TO ALLIANCE NEBRASKA. HOWEVER...EXPECT THESE WINDS TO BE BRIEF AND LOCALIZED. HIGH TEMPS WILL BE NEAR NORMAL TODAY WITH WEST TO NORTHWEST FLOW. TONIGHT AND THURSDAY...ALL MODELS INDICATE AN UPPER LEVEL RIDGE OF HIGH PRESSURE QUICKLY BUILDING ALONG THE ROCKIES AND ACROSS THE HIGH PLAINS AHEAD OF THE NEXT PACIFIC STORM SYSTEM PUSHING ONSHORE TODAY. WINDS WILL BECOME LIGHT AND SHIFT INTO THE EAST OR SOUTHEAST AS SURFACE HIGH PRESSURE DEVELOPS OVER THE NORTHERN AND CENTRAL PLAINS WEDNESDAY NIGHT AND A SURFACE LOW PUSHES ACROSS THE GREAT BASIN AND INTO UTAH TONIGHT. WITH UPSLOPE LLVL WINDS...WILL NEED TO MONITOR LOW STRATUS AND FOG EAST OF THE LARAMIE RANGE LATE TONIGHT INTO THURSDAY MORNING. KEPT SOME PATCHY FOG IN THE FORECAST FOR PORTIONS OF THE HIGH PLAINS AND NORTH PLATTE RIVER VALLEY WITH THE SREF HIGHLIGHTING THESE AREAS WITH THE HIGHEST POTENTIAL TO SEE FOG...ALTHOUGH IT HAS BEEN TRENDING LOWER WITH FOG POTENTIAL THE LAST FEW RUNS. EXPECT SCATTERED RAIN/SNOW SHOWERS TO DEVELOP ACROSS WYOMING AND WESTERN NEBRASKA DURING THE DAY ON THURSDAY AND CONTINUE INTO THURSDAY EVENING AS A WEAKENING UPPER LEVEL TROUGH QUICKLY MOVES ACROSS THE REGION. SNOW LEVELS WILL BE ABOVE 5500 FEET SO SNOW ACCUMULATIONS WILL NOT BE A CONCERN AS THE SHORT WAVE WILL MOVE QUICKLY ACROSS WYOMING AND INTO THE GREAT PLAINS BY THURSDAY NIGHT. TEMPS WILL BE NEAR OR SLIGHTLY ABOVE NORMAL THURSDAY. .LONG TERM...THE 00Z ECMWF AND GEFS SEEM TO HAVE A DECENT HANDLE OF THE MID/UPPER LEVEL FEATURES DURING THE UPCOMING MEDIUM RANGE FORECAST PERIOD. SHORTWAVE RIDGE WILL BE TRANSLATING EAST ACROSS WYOMING AND THE NORTHERN HIGH PLAINS FRIDAY. MEANWHILE A CLOSED LOW ALONG THE OREGON COAST OPENS INTO A SHORTWAVE AS IT MOVES INTO MONTANA AND WYOMING FRIDAY NIGHT AND NORTHERN HIGH PLAINS ON SATURDAY. THIS SYSTEM WILL BRING INCREASING CHANCES FOR RAIN/SNOW SHOWERS. ELEVATIONS ABOVE 9000 FT COULD SEE 2 TO 4 INCHES OF SNOW ACCUMULATING FROM FRIDAY MORNING THROUGH SATURDAY AFTERNOON. LOWER ELEVATIONS NEAR THE LARAMIE RANGE AND CARBON COUNTY MAY SEE UP TO AN INCH. HIGH TEMPERATURES FRIDAY WILL BE NEAR SEASONAL AVERAGES...THEN COOL ABOUT 5 TO 7 DEGREES SATURDAY BEHIND A PACIFIC COLD FRONT. RIDGING ALOFT SLIDES EAST ACROSS THE REGION SATURDAY NIGHT...FOLLOWED BY A MORE SIGNIFICANT TROUGH DIGGING INTO THE FOUR CORNERS REGION SUNDAY...AND TOWARD THE SOUTHERN HIGH PLAINS SUNDAY NIGHT. THE ECMWF AND GEFS HAVE BEEN CONSISTENTLY TRACKING THE CLOSED LOW ACROSS NORTHERN ARIZONA AND NEW MEXICO...WITH THE BEST DYNAMICS AND LIFT TO THE SOUTH OF THE CWA. WITH THE SURFACE LOW MOVING ACROSS SOUTHERN COLORADO AND A DECENT SOUTHEASTERLY FETCH OF GULF MOISTURE WRAPPING TO THE NORTH...CHANCES FOR RAIN/SNOW SHOWERS WILL BE FAVORED OVER THE SOUTHERN 2/3 OF THE CWA. BEST CHANCES FOR ACCUMULATING SNOW WILL BE OVER THE NORTHERN LARAMIE RANGE AND SNOWY/SIERRA MADRE RANGES. HIGH TEMPERATURES SUNDAY AND MONDAY WILL AVERAGE ABOUT 5 DEGREES BELOW NORMAL. THE PRECIPITATION WILL TAPER OFF MONDAY AS THE TROUGH AND SURFACE LOW MOVE INTO THE CENTRAL/SOUTHERN PLAINS. DRIER CONDITIONS WILL RETURN TO THE CWA MONDAY NIGHT AND TUESDAY...WITH ISOLATED OROGRAPHIC SNOW SHOWERS POSSIBLE FOR THE SNOWY AND SIERRA MADRE RANGES. THE PROGRESSIVE QUASI-ZONAL FLOW WILL USHER IN THE NEXT SHORTWAVE TROUGH...MOVING SOUTHEAST FROM THE PACIFIC NORTHWEST COAST ACROSS THE GREAT BASIN AND TOWARD THE FOUR CORNERS TUESDAY NIGHT AND WEDNESDAY. THE GFS MAINTAINS A SLIGHTLY WEAKER AND MORE NORTHERN TRACK OF THE CLOSED LOW (OVER CENTRAL UTAH) THAN THE MORE ROBUST ECMWF (OVER SOUTHERN NEVADA). IN EITHER CASE...MOISTURE WILL BE RETURNING TO THE CWA WITH ISOLATED TO SCATTERED RAIN/SNOW SHOWERS. HIGH TEMPERATURES TUESDAY AND WEDNESDAY WILL AVERAGE ABOUT 5 DEGREES ABOVE NORMAL. && .AVIATION...12Z TAF ISSUANCE COULD SEE A BRIEF PERIOD OF MVFR CIGS/VSBYS IN LIGHT SNOW/FOG FROM KBFF TO KAIA AROUND SUNRISE AS AN UPPER LEVEL DISTURBANCE EXITS THE NEB PANHANDLE. OTHERWISE...VFR WILL PREVAIL THROUGH WEDNESDAY EVENING. IT WILL CONTINUE TO BE WINDY WITH WEST TO NORTHWEST WINDS SUSTAINED BETWEEN 15 AND 25 KT WITH GUSTS TO 40 KT AT TIMES. THE WINDS WILL DIMINISH THIS EVENING AS A RIDGE BUILDS OVER THE REGION AND PRESSURE GRADIENT RELAXES SOMEWHAT. && .FIRE WEATHER...ALTHOUGH BREEZY CONDITIONS WILL CONTINUE TODAY WITH GUSTS UP TO 45 MPH IN A FEW AREAS EAST OF THE LARAMIE RANGE...HUMIDITIES ARE EXPECTED TO BE HIGHER COMPARED TO YESTERDAY WITH MIN HUMIDITIES BETWEEN 25 TO 40 PERCENT ACROSS MOST OF SOUTHEAST WYOMING AND WESTERN NEBRASKA WITH EXCELLENT NIGHTTIME RECOVERIES. FIRE WEATHER CONCERNS ARE MINIMAL THROUGH LATE THIS WEEK AND INTO NEXT WEEKEND WITH COOL TEMPS AND SEVERAL CHANCES OF PRECIPITATION. && .HYDROLOGY...GLENDO AND GUERNSEY DAMS CONTINUE TO HAVE SIGNIFICANT RELEASES OF WATER IN ANTICIPATION OF MOUNTAIN SNOW MELT LATER THIS SPRING AND EARLY SUMMER. THE RELEASES OF WATER WILL CONTINUE TO HAVE IMPACTS DOWNSTREAM ON THE NORTH PLATTE RIVER. IN FACT RIVER LEVELS ALL ALONG THE NORTH PLATTE RIVER ARE AT OR NEAR ACTION STAGE. THESE LEVELS WILL REMAIN STEADY UNTIL ADDITIONAL RELEASES TAKE PLACE AT GUERNSEY RESERVOIR. THE NORTH PLATTE RIVER DOWNSTREAM OF GUERNSEY RESERVOIR WILL REMAIN AT HIGH LEVELS FOR THE FORESEEABLE FUTURE. CURRENT RIVER FORECASTS SHOW THE NORTH PLATTE RIVER NEAR MITCHELL TO INCREASE TO NEAR FLOOD STAGE BY THURSDAY OR FRIDAY. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && SHORT TERM/FIRE WEATHER...TJT LONG TERM/AVIATION...JAMSKI HYDROLOGY...CYS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHEYENNE WY 1006 PM MDT TUE MAR 22 2011 WYZ101>119-231115- 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- 1006 PM MDT TUE MAR 22 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST WYOMING. .DAY ONE...TONIGHT A HIGH WIND WARNING REMAINS IN EFFECT FOR THE LARAMIE RANGE FOOTHILLS WEST OF CHEYENNE AS WELL AS THE ARLINGTON AREA UNTIL 4 AM. WINDS IN THOSE AREAS WILL GUST AS HIGH AS 60 MPH UNTIL 4 AM BEFORE DIMINISHING TO AROUND 50 MPH. AREAS OF BLOWING SNOW WILL REDUCE VISIBILITIES IN THE ARLINGTON AREA UNTIL 4 AM. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY A SERIES OF PACIFIC STORM SYSTEMS WILL PUSH ACROSS WYOMING THROUGH THE WEEKEND...RESULTING IN A HIGHER CHANCE OF WIDESPREAD PRECIPITATION ACROSS THE AREA. SNOW ACCUMULATIONS ARE POSSIBLE THIS WEEKEND EVEN IN THE LOWER ELEVATIONS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TONIGHT. && THIS PRODUCT...ALONG WITH OTHER WEATHER...HYDROLOGIC...AND CLIMATE INFORMATION IS AVAILABLE ON THE WEB AT... HTTP://WEATHER.GOV/CHEYENNE NEZ002-003-019>021-054-055-095-096-231115- DAWES-BOX BUTTE-SCOTTS BLUFF-BANNER-MORRILL-KIMBALL-CHEYENNE- NORTH SIOUX-SOUTH SIOUX- 1006 PM MDT TUE MAR 22 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE WESTERN NEBRASKA PANHANDLE. .DAY ONE...TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY A SERIES OF PACIFIC STORM SYSTEMS WILL PUSH ACROSS WYOMING AND WESTERN NEBRASKA THROUGH THE WEEKEND...RESULTING IN A HIGHER CHANCE OF WIDESPREAD PRECIPITATION ACROSS THE AREA. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TONIGHT. && THIS PRODUCT...ALONG WITH OTHER WEATHER...HYDROLOGIC...AND CLIMATE INFORMATION IS AVAILABLE ON THE WEB AT... HTTP://WEATHER.GOV/CHEYENNE WEILAND
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
1249 AM MDT WED MAR 23 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1045 PM NON-TSTM WND GST 4 ESE I-80 EXIT 345 41.08N 105.04W
03/22/2011 M71.00 MPH LARAMIE WY MESONET
EMKAY UP226 SITE.
1145 PM HIGH SUST WINDS 4 ESE I-80 EXIT 345 41.08N 105.04W
03/22/2011 M52.00 MPH LARAMIE WY MESONET
EMKAY UP226 SITE. GUST 61 MPH.
&&
MJAMSKIPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
109 AM MDT WED MAR 23 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1215 AM NON-TSTM WND GST 4 ESE I-80 EXIT 345 41.08N 105.04W
03/23/2011 M60.00 MPH LARAMIE WY MESONET
EMKAY UP226 SITE. SUSTAINED WIND 46 MPH.
&&
MJAMSKIThe national radar mosaic for the moment the first event began.
2 high wind. Local standard time, as filed.
UPR sensor at Emkay measured sustained winds of 40 mph or greater with a peak gust of 62 mph at 23/0645 MST.
UPR sensor at Buford measured sustained winds of 40 mph or greater with a peak gust of 74 mph at 23/0900 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, 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: 283061, 283060.