A fast moving upper level disturbance and tight surface pressure gradient produced very strong west winds. Gusts of 55 to 65 mph were observed, especially between Laramie and Rawlins.
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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 CYS wrote it up.
A fast moving upper level disturbance and tight surface pressure gradient produced very strong west winds. Gusts of 55 to 65 mph were observed, especially between Laramie and Rawlins.
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 Dec 23, 8:23 PM MST, 1 hour 52 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE CHEYENNE WY
823 PM MST WED DEC 23 2015
.UPDATE...
ISSUED AT 823 PM MST WED DEC 23 2015
AS WINDS CAME UP AT ARLINGTON, WY VISIBILITIES WENT TO ZERO.
EXPECT THESE WHITEOUT CONDITIONS TO CONTINUE INTO THE EARLY
MORNING HOURS WITH WINDS 40 TO 60 MPH PRODUCING VERY LOW
VISIBILITIES IN BLOWING SNOW. WE UPGRADED THE WINTER WEATHER
ADVISORY THAT AREA AND STRETCH OF INTERSTATE 80 WEST OF LARAMIE
AND EAST OF RAWLINS TO A BLIZZARD WARNING. WYDOT REPORTING VERY
DANGEROUS CONDITIONS WITH ZERO VISIBILITY AND DRIFTED SNOW. NOT
SOMETHING WE WANT FOLKS TO GET STUCK OUT IN...SO THIS SHOULD
HEIGHTEN MESSAGE TO AVOID THAT AREA AND STRETCH OF I-80 FOR
TRAVEL TONIGHT. AT THIS TIME WYDOT STILL REPORTING EASTBOUND
SECTION OF I-80 OPEN...BUT AGAIN WE WOULD HIGHLY DISCOURAGE TRAVEL
THROUGH THERE TONIGHT.
BORDEAUX AREA OF INTERSTATE 25 (NEAR WHEATLAND) WAS GUSTING TO 51
MPH EARLIER THIS EVENING BUT SINCE WINDS HAVE DROPPED BACK TO
GUSTS TO 35 MPH. WILL HANG ON TO HIGH WIND WARNINGS WHERE WE HAVE
THEM ELSEWHERE IN WIND PRONE AREAS...THINKING BLOWING SNOW NOT AS
BIG OF AN ISSUE THERE GIVEN LESS SNOWFALL PREVIOUSLY AS COMPARED
TO ARLINGTON.
UPDATE ISSUED AT 452 PM MST WED DEC 23 2015
ISSUED WINTER WEATHER ADVISORY FOR BLOWING SNOW FOR THE ARLINGTON
AND ELK MOUNTAIN LOCATIONS THROUGH MIDNIGHT TONIGHT.
UPDATE ISSUED AT 436 PM MST WED DEC 23 2015
CANCELLED WINTER STORM WARNING FOR THE SNOWY AND SIERRA MADRE
RANGES.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 230 PM MST WED DEC 23 2015
TONIGHT...INHERITED HIGH WIND WATCH LOOKS ON TRACK. AS THE SHORTWAVE
TROUGH ALOFT MOVES PAST OUR AREA...SUBSIDENCE TAKES OVER. THROUGH
03Z...OUR LOCAL PRODUCT SHOWS THE CRAIG TO CASPER 700 MB HEIGHT
GRADIENTS FROM 60 TO 65 METERS AS A 50 KNOT JETLET MOVES THROUGH.
WILL UPGRADE TO A HIGH WIND WARNING BASED ON THESE TRENDS...ALTHOUGH
AGAIN IT IS A BORDERLINE EVENT. AFTER MIDNIGHT...SNOWS SHOULD END
EXCEPT OVER AND NEAR OUR NORTHERN LARAMIE...SNOWY AND SIERRA MADRE
RANGES DUE TO OROGRAPHICS.
THURSDAY...RELATIVELY DOCILE DAY AS THE FLOW ALOFT TURNS WEST
SOUTHWEST. WITH LIMITED LOW AND MID LEVEL MOISTURE...A DRY DAY ON
TAP. CLOUD COVER WILL LIMIT WARMING POTENTIAL.
CHRISTMAS EVE/CHRISTMAS DAY...NEXT SHORTWAVE TROUGH ALOFT MOVES
ACROSS SOUTHERN NEVADA. LOOKS LIKE THE BULK OF SNOW WILL REMAIN OFF
TO OUR SOUTHWEST IN COLORADO...THOUGH OUR SNOWY AND SIERRA MADRE
RANGES SHOULD SEE CHANCES FOR SNOW INCREASE AFTER MIDNIGHT.
DECENT DIFFERENCES WITH THE SPEED OF THE SYSTEM ON THE NAM VERSUS
THE GFS. THE NAM IS SLOWER THAN THE GFS...WHICH SPREADS SNOW ACROSS
OUR ENTIRE FORECAST AREA CHRISTMAS AFTERNOON. SINCE THIS HAS BEEN
OUR TIMING ALL ALONG...WILL DISREGARD THE SLOWER NAM SOLUTION AND
MAINTAIN DECENT CHANCES FOR SNOW ON CHRISTMAS AFTERNOON TO MAINTAIN
CONTINUITY. CONTINUED COLD PER 700 MB TEMPERATURES NEAR -13 CELSIUS
AND PROGGED THICKNESSES.
FRIDAY NIGHT...MAIN PART OF THE SNOWFALL EVENT TAKES SHAPE WITH
SATURATED LOW AND MID LEVELS AND THE DYNAMICS OVER THE COLD DOME.
DECENT CHANCES FOR LIGHT SNOW...THOUGH WITH SIGNIFICANT TIMING
DIFFERENCES BETWEEN THE MODELS...WILL NOT GO TOO HIGH ON POPS JUST
YET. TOTAL SNOWFALL AMOUNTS LOOK LIKE A FEW AREAS WILL SEE ADVISORY
CRITERIA SNOW. COLD WIND CHILL TEMPERATURES WITH PROGGED OVERNIGHT
LOWS AND NORTH WINDS 15 TO 20 MPH GUSTING TO 30 MPH.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 230 PM MST WED DEC 23 2015
SOME LINGERING LIGHT SNOW WILL COME TO AN END SATURDAY MORNING AS
THE UPPER TROF AXIS SLIPS EAST OF THE AREA AND DYNAMICAL SUPPORT
WANES SIGNIFICANTLY. QUITE A CHILLY DAY SATURDAY AS A COLD SURFACE
HIGH BUILDS DOWN THE NORTHERN PLAINS WITH MAX TEMPS LIKELY ONLY
ATTAINING THE TEENS OVER MANY LOCALES. DRY AND WARMER SUNDAY
THOUGH STILL ON THE COOL SIDE WITH AN UPPER RIDGE TILTING EAST
OVER THE CWA ATOP CUT-OFF UPPER LOW OVER SW TEXAS. MODELS IN
DECENT AGREEMENT IN LIFTING THIS UPPER LOW NORTHEAST OVER THE
SOUTHERN PLAINS INTO MISSOURI BY MONDAY NIGHT...KEEPING THE
ASSOCIATED PCPN SHIELD EAST OF THE CWA. MEANWHILE ANOTHER UPPER
SHORTWAVE DROPS INTO THE SW CONUS AND CLOSES OFF AN UPPER LOW
AROUND THE AZ/NEW MEXICO BORDER BY TUESDAY MORNING...THEN TRY TO
PHASE IT WITH SOME NORTHERN STREAM ENERGY BY LATE TUESDAY AS IT
MOVES OUT OVER THE PLAINS. THIS COULD BRING SOME MAINLY MTN SNOW
SHOWERS BUT MOISTURE RATHER LIMITED WITH THIS SYSTEM. WEDS LOOKING
GENERALLY DRY AND COOL THOUGH SOME MORE NORTHERN STREAM IMPULSES
MAY INFLUENCE THE AREA WEATHER THEN.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY MORNING)
ISSUED AT 823 PM MST WED DEC 23 2015
SNOWBAND THAT MOVED THROUGH CHEYENNE EARLIER PRODUCING IFR
VISIBILITIES NOW MOVING THROUGH SIDNEY. EXPECT VISIBILITIES TO
IMPROVE AT SIDNEY WITHIN THE NEXT 3 HOURS AS THE BAND MOVES EAST.
ELSEWHERE...MVFR CEILINGS WILL CONTINUE UNTIL SHORTLY BEFORE
DAYBREAK AT RAWLINS...WITH MVFR/VFR CONDITIONS EXPECTED ELSEWHERE
WITH A SLIGHT VISIBILITY RESTRICTION AT CHEYENNE PERIODICALLY TO
MVFR IN BLOWING SNOW AS WINDS PERIODICALLY PICK UP TO AROUND 35
KTS ON GUSTS.
&&
.FIRE WEATHER...
ISSUED AT 230 PM MST WED DEC 23 2015
NO CONCERNS BASED ON PROJECTED WINDS AND HUMIDITIES.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...BLIZZARD WARNING UNTIL 5 AM MST THURSDAY FOR WYZ110.
HIGH WIND WARNING UNTIL 5 AM MST THURSDAY FOR WYZ106-116-117.
NE...NONE.VFR CONDITIONS WILL PREVAIL THROUGH MUCH OF THE TAF PERIOD. A FAST
MOVING UPPER SYSTEM WILL BRING A PERIOD OF SNOW SHOWERS TO PARTS OF
THE AREA THIS EVENING WITH A PERIOD OF MAINLY MVFR CIGS AND VSBYS
ASSOCIATED WITH THE SNOW SHOWERS. GUSTY WINDS AROUND THE SE WY MTNS
TONIGHT BEHIND THE UPPER SYSTEM.&&
UPDATE...JG
SHORT TERM...RUBIN
LONG TERM...RE
AVIATION...RE
FIRE WEATHER...RUBINHAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHEYENNE WY 452 PM MST WED DEC 23 2015 WYZ101>119-241230- 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- 452 PM MST WED DEC 23 2015 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL WYOMING...SOUTH CENTRAL WYOMING AND SOUTHEAST WYOMING. .DAY ONE...TONIGHT A WINTER WEATHER ADVISORY FOR BLOWING SNOW IS IN EFFECT UNTIL MIDNIGHT FOR THE ARLINGTON AND ELK MOUNTAIN AREAS. EXPECT STRONG WEST WINDS TO PRODUCE BLOWING SNOW...NEAR ZERO VISIBILITIES AND VERY ICY ROADS THIS EVENING. A HIGH WIND WARNING HAS BEEN ISSUED FROM 7 PM THIS EVENING TO 5 AM THURSDAY MORNING FOR ARLINGTON...BORDEAUX...THE INTERSTATE 80 SUMMIT INCLUDING VEDAUWOO AND BUFORD AND SOUTHERN LARAMIE RANGE AND FOOTHILLS. EXPECT WEST WINDS OF 35 TO 45 MPH WITH GUSTS TO 65 MPH. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY A STORM SYSTEM WILL MOVE ACROSS THE REGION ON CHRISTMAS. SNOW AND VERY COLD TEMPERATURES COULD HAVE AN IMPACT ON CHRISTMAS TRAVEL PLANS ACROSS THE AREA...SO BE SURE TO MONITOR THE LATEST FORECAST INFORMATION OVER THE NEXT FEW DAYS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE REQUIRED. NEZ002-003-019>021-054-055-095-096-241230- DAWES-BOX BUTTE-SCOTTS BLUFF-BANNER-MORRILL-KIMBALL-CHEYENNE- NORTH SIOUX-SOUTH SIOUX- 452 PM MST WED DEC 23 2015 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WESTERN NEBRASKA. .DAY ONE...TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY A STORM SYSTEM WILL MOVE ACROSS THE REGION ON CHRISTMAS. SNOW AND VERY COLD TEMPERATURES COULD HAVE AN IMPACT ON CHRISTMAS TRAVEL PLANS ACROSS THE AREA...SO BE SURE TO MONITOR THE LATEST FORECAST INFORMATION OVER THE NEXT FEW DAYS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE REQUIRED. RUBIN
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE CHEYENNE WY 525 PM MST WED DEC 23 2015 NEZ019>021-054-055-WYZ108-118-119-240245- SCOTTS BLUFF-BANNER-MORRILL-KIMBALL-CHEYENNE-GOSHEN COUNTY- CENTRAL LARAMIE COUNTY-EAST LARAMIE COUNTY- INCLUDING THE CITIES OF...SCOTTSBLUFF...GERING...HARRISBURG... BRIDGEPORT...BAYARD...KIMBALL...SIDNEY...TORRINGTON...CHEYENNE... BURNS...CARPENTER...ALBIN...PINE BLUFFS 525 PM MST WED DEC 23 2015 ...BAND OF SNOW MOVING EAST ACROSS THE AREA CREATING SLICK ROAD CONDITIONS AND REDUCED VISIBILITIES... A BAND OF HEAVY SNOWFALL MOVING EAST ACROSS EXTREME SOUTHEAST WYOMING IS CREATING SLICK ROAD CONDITIONS AS IT MOVES SLOWLY EAST. THIS BAND OF HEAVY SNOW WILL CONTINUE MOVING EAST INTO THE SOUTHERN NEBRASKA PANHANDLE THROUGH 8 PM WHERE SIMILAR IMPACTS TO ROAD CONDITIONS CAN BE EXPECTED EARLY THIS EVENING. MOTORISTS SHOULD SLOW DOWN AND TAKE EXTRA TIME GETTING TO WHERE THEY NEED TO GO THIS EVENING. BE PREPARED FOR SLICK ROAD CONDITIONS AND LEAVE A SAFE DISTANCE BETWEEN VEHICLES AS THIS SNOW BAND MOVES ACROSS THE REGION.
The national radar mosaic for the moment the first event began.
6 high wind. Local standard time, as filed.
The WYDOT sensor at Wagonhound measured sustained winds of 40 mph or higher, with a peak gust of 58 mph at 23/2315 MST.
The WYDOT sensor at Arlington measured sustained winds of 40 mph or higher, with a peak gust of 61 mph at 23/2300 MST.
The WYDOT sensor at Halleck Ridge measured sustained winds of 40 mph or higher, with a peak gust of 65 mph at 24/0015 MST.
The WYDOT sensor at Bordeaux measured sustained winds of 40 mph or higher.
The WYDOT sensor at Vedauwoo measured sustained winds of 40 mph or higher.
The UPR sensor at Emkay measured sustained winds of 40 mph or higher.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2015Every state in 2015This day in weather historyWarnings in Wyoming, December 2015
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: 613807, 613805, 613806, 613802, 613829, 613830.