A prolonged period of high winds developed through the wind corridors of southeast Wyoming and eventually spread onto the plains. Frequent wind gusts of 55 to 75 mph were observed.
Every event with a place to put it; 53 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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 prolonged period of high winds developed through the wind corridors of southeast Wyoming and eventually spread onto the plains. Frequent wind gusts of 55 to 75 mph were observed.
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 6, 8:32 PM MST, 1 hour 38 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
832 PM MST SUN DEC 6 2015
.UPDATE...
ISSUED AT 817 PM MST SUN DEC 6 2015
OVERNIGHT FORECAST TONIGHT IN NICE SHAPE FROM OUR DAY SHIFT
FORECAST TEAM...INCLUDING THE HIGH WIND WARNING STARTING AT 11 PM
THIS EVENING FOR THE NORTH SNOWY RANGE FOOTHILLS AND SOUTHERN
LARAMIE RANGE INCLUDING ARLINGTON...ELK MOUNTAIN...VEDAUWOO...
BUFORD AND PUMPKIN VINE.
FAST MOVING AND LOW AMPLITUDE SHORTWAVE TROUGH ALOFT MOVES EAST
INTO SOUTHEAST WYOMING BY MIDNIGHT...THEN TO NORTH CENTRAL
NEBRASKA BY DAWN. ASSOCIATED RELATIVELY WEAK COLD FRONT ALSO
MOVES THROUGH. EARLY EVENING WINDS ALREADY GUSTING 35 TO 45 MPH
IN THE FUTURE HIGH WIND WARNING LOCATIONS...AND EXPECT THESE
GUSTS TO INCREASE EVEN MORE AFTER MIDNIGHT IN THE SUBSIDENT
SECTOR BEHIND THE SHORTWAVE TROUGH ALOFT AS SHOWN ON THE
500-300 MB AND 700-500 MB LAYER QUASIGEOSTROPHIC DOWNWARD FORCING
AS WELL AS A 50 KNOT 700 MB JETLET MOVING THROUGH...SO WOULD NOT
BE SURPRISED TO SEE GUSTS NEAR 60 MPH LATE TONIGHT NEAR ARLINGTON
AND OVER THE INTERSTATE 80 SUMMIT. ALSO OUR LOCAL HIGH WIND
GRADIENTS SHOW 50 TO 55 METER 700 MB CRAIG TO CASPER GRADIENTS
BY DAWN MONDAY AND AS THEY INCREASE...SO SHOULD THE WIND GUSTS.
ALSO ADJUSTED TEMPERATURES...DEWPOINTS AND CLOUD COVER FOR THE
REST OF THE NIGHT BASED ON TRENDS AND THE 00Z NAM.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 257 PM MST SUN DEC 6 2015
WINDS ARE BEGINNING TO INCREASE THIS AFTN AS A LEE TROUGH
STRENGTHENS IN ADVANCE OF THE SHORTWAVE CURRENTLY ACROSS IDAHO.
STILL STRUGGLING TO SEE GUSTS ABOVE 35-40 MPH BUT THIS SHOULD CHANGE
BY LATER TONIGHT. THE 850MB CAG-CPR GRADIENT INCREASES TO AROUND 55
METERS BY 12Z MON AND THEN LEVELS OFF THROUGH MON AFTN. DECIDED TO
UPGRADE TO A HIGH WIND WARNING FOR THE ARLINGTON AREA AND SOUTHERN
LARAMIE RANGE WHERE CONFIDENCE IS HIGHEST. DUE TO THE MARGINAL
NATURE OF THIS EVENT...DELAYED THE START TIME OF THE REST OF THE
WATCHES UNTIL THE STRONGEST WINDS ARRIVE ON MONDAY NIGHT. IT IS
STILL LIKELY THAT A FEW LOCATIONS WILL APPROACH HIGH WIND IN THE
SOUTHERN LARAMIE RANGE FOOTHILLS AND BORDEAUX OVERNIGHT...HOWEVER IT
DOES NOT APPEAR TO BE A WIDESPREAD EVENT.
THE HIGHER WINDS AND A MORE WIDESPREAD HIGH WIND EVENT OVER MOSTLY
THE WIND PRONE AREAS WILL LIKELY OCCUR MON NIGHT THROUGH TUES
MORNING. THIS IS IN RESPONSE TO A SHORTWAVE MOVING FROM MONTANA
INTO THE NORTHERN PLAINS. THE LLVL GRADIENT IS MAXIMIZED AT 12Z
TUES AROUND 75 METERS OFF THE GFS. INCLUDED CENTRAL LARAMIE COUNTY
(CHEYENNE) IN THE HIGH WIND WATCH AS SOUNDINGS INDICATE 60 KTS AT 2-
3 THOUSAND FEET AGL. COULD ALSO SEE WIND ADVISORY CONDITIONS OVER
PORTIONS OF THE PANHANDLE DURING THE DAYTIME IN THE SUBSIDENCE AND
GOOD LLVL MIXING BEHIND THE UPPER WAVE. TEMPS WILL CONTINUE TO BE
ABOVE NORMAL ESPECIALLY AT NIGHT WITH THE ELEVATED WINDS.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 257 PM MST SUN DEC 6 2015
STRONG WINDS WILL BE THE MAIN FORECAST CONCERN FOR MIDDLE PORTIONS
OF NEXT WEEK...THEN INCREASING CHANCES FOR SNOW FRIDAY INTO NEXT
WEEKEND. ALSO LOOKING AT MUCH COLDER TEMPERATURES GOING INTO NEXT
WEEKEND AS A SHOT OF ARCTIC AIR IS VERY LIKELY.
MODELS GENERALLY REMAIN DRY THROUGH THURSDAY AFTERNOON. QUICK MOVING
SHORTWAVES OF VARYING STRENGTH WILL MOVE ACROSS THE FORECAST AREA
TUESDAY NIGHT THROUGH THURSDAY AFTERNOON. WHILE THE MODELS ARE
GENERALLY NOT PRODUCING QPF...CAN NOT RULE OUT SOME SNOW INTO THE
MOUNTAINS...PARTICULARLY THE SNOWY AND SIERRA MADRE RANGES.
STRONG WESTERLY UPSLOPE FLOW FOR THOSE MOUNTAINS IS CONDUCIVE OF
ACCUMULATING SNOW SHOULD EVEN A LITTLE BIT OF MOISTURE SNEAK
ACROSS THE PACIFIC NORTHWEST. EAST OF THE LARAMIE RANGE IT IS VERY
UNLIKELY ANY PRECIPITATION WILL REACH THE GROUND THROUGH THURSDAY
AS DOWNSLOPE FLOW REMAINS IN PLACE.
AS FOR THE WINDS...SHOULD SEE WINDS RELAXING TUESDAY NIGHT INTO
WEDNESDAY AS A STRONG UPPER LEVEL JET EXITS THE REGION. WINDS WILL
REMAIN ELEVATED INTO THE WIND PRONE PORTIONS OF SOUTHEAST WYOMING
WEDNESDAY BUT IT APPEARS THE BETTER POTENTIAL FOR STRONG WINDS WILL
BE WEDNESDAY NIGHT AS THE NOSE OF AN UPPER LEVEL JET NOSE INTO THE
AREA. THIS COULD BE A PSEUDO BORA WIND EVENT AS A QUICK SHOT OF
COOL AIR MOVES ACROSS THE AREA IN ASSOCIATION WITH A PASSING
SHORTWAVE. OF COURSE TIMING OF ANY GIVEN WEATHER FEATURE IS MUCH
TO BE DESIRED BY LATER NEXT WEEK GIVEN FAST MOVING ZONAL FLOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 443 PM MST SUN DEC 6 2015
VFR. SCATTERED TO BROKEN CLOUDS AT OR ABOVE 12000 FEET AGL.
WYOMING TAFS...GUSTS OF 25 TO 28 KNOTS AT RAWLINS...18 TO 27 KNOTS
AT LARAMIE AND UP TO 29 KNOTS AT CHEYENNE AFTER 04Z.
NEBRASKA TAFS...GUSTS UP TO 21 KNOTS AT CHADRON FROM 06Z TO 08Z...
UP TO 20 KNOTS AT SCOTTSBLUFF AFTER 18Z...AND UP TO 23 KNOTS AT
SIDNEY AFTER 18Z.
&&
.FIRE WEATHER...
ISSUED AT 257 PM MST SUN DEC 6 2015
BREEZY TO WINDY CONDITIONS WILL OCCUR OVER MUCH OF THE AREA TONIGHT
THOUGH WEDNESDAY. THE PERIOD OF STRONGEST WINDS WILL LIKELY OCCUR
MONDAY NIGHT THROUGH TUESDAY AFTERNOON. HOWEVER WITH MINIMUM
AFTERNOON HUMIDITY VALUES GENERALLY ABOVE 25 PERCENT...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WARNING UNTIL 11 AM MST TUESDAY FOR WYZ110-116.
HIGH WIND WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR
WYZ106-117-118.
NE...NONE.
&&
UPDATE...RUBIN
SHORT TERM...ZF
LONG TERM...SML
AVIATION...RUBIN
FIRE WEATHER...ZFHAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHEYENNE WY 135 PM MST SUN DEC 6 2015 NEZ002-003-019>021-054-055-095-096-WYZ101>105-107>109-111>115-119- 072045- 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-EAST PLATTE COUNTY- GOSHEN COUNTY-CENTRAL CARBON COUNTY-SOUTHWEST CARBON COUNTY- SIERRA MADRE RANGE-UPPER NORTH PLATTE RIVER BASIN-SNOWY RANGE- LARAMIE VALLEY-EAST LARAMIE COUNTY- 135 PM MST SUN DEC 6 2015 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WESTERN NEBRASKA...EAST CENTRAL WYOMING...SOUTH CENTRAL WYOMING AND SOUTHEAST WYOMING. .DAY ONE...TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY AN EXTENDED PERIOD OF BREEZY TO WINDY CONDITIONS IS LIKELY ACROSS SOUTHEAST WYOMING AND THE WESTERN NEBRASKA PANHANDLE THIS WEEK. AT THIS TIME...THE STRONGEST WINDS ARE EXPECTED FROM TUESDAY MORNING THROUGH EARLY AFTERNOON. THE NEXT CHANCE FOR WIDESPREAD SNOW WILL OCCUR ON FRIDAY WITH THE PASSAGE OF A STRONG COLD FRONT. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE REQUIRED. WYZ106-110-116>118-072045- CENTRAL LARAMIE RANGE AND SOUTHWEST PLATTE COUNTY- NORTH SNOWY RANGE FOOTHILLS-SOUTH LARAMIE RANGE- SOUTH LARAMIE RANGE FOOTHILLS-CENTRAL LARAMIE COUNTY- 135 PM MST SUN DEC 6 2015 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL WYOMING...SOUTH CENTRAL WYOMING AND SOUTHEAST WYOMING. .DAY ONE...TONIGHT STRONG WINDS ARE EXPECTED TO DEVELOP OVER THE ARLINGTON AREA AND SOUTHERN LARAMIE RANGE BY TONIGHT. WINDS WILL GUST TO 60 MPH AND A HIGH WIND WARNING IS IN EFFECT. A FEW GUSTS TO 55 MPH WILL ALSO BE POSSIBLE IN THE SOUTHERN LARAMIE RANGE FOOTHILLS AND BORDEAUX AREA. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY PERIODS OF HIGH WINDS MAY CONTINUE OVER THE PRIMARY WIND CORRIDORS THROUGH WEDNESDAY NIGHT. THE NEXT CHANCE FOR WIDESPREAD SNOW WILL OCCUR ON FRIDAY WITH THE PASSAGE OF A STRONG COLD FRONT. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE REQUIRED.
The national radar mosaic for the moment the first event began.
53 high wind. Local standard time, as filed.
The WYDOT sensor at Pumpkin Vine measured sustained winds of 40 mph or higher, with a peak gust of 65 mph at 06/2255 MST.
The WYDOT sensor at Bordeaux measured sustained winds of 40 mph or higher, with a peak gust of 72 mph at 07/2230 MST.
The WYDOT sensor at Halleck Ridge measured sustained winds of 40 mph or higher, with a peak gust of 71 mph at 07/2300 MST.
The WYDOT sensor at Cooper Cove measured sustained winds of 40 mph or higher, with a peak gust of 75 mph at 07/1425 MST.
The WYDOT sensor at Lone Tree measured sustained winds of 40 mph or higher, with a peak gust of 68 mph at 07/0926 MST.
The WYDOT sensor at Arlington measured sustained winds of 40 mph or higher, with a peak gust of 68 mph at 07/1536 MST.
The WYDOT sensor at Buford East measured wind gusts of 58 mph or higher, with a peak gust of 72 mph at 07/0801 MST.
The WYDOT sensor at Wildcat Trail measured wind gusts of 58 mph or higher, with a peak gust of 74 mph at 07/0810 MST.
The WYDOT sensor at Bear Creek measured sustained winds of 40 mph or higher, with a peak gust of 6 1mph at 07/0435 MST.
The WYDOT sensor at Interstate 80 mile marker 353 measured sustained winds of 40 mph or higher, with a peak gust of 69 mph at 07/0940 MST.
The WYDOT sensor at Hynds Lodge Road measured peak wind gusts of 58 mph or higher, with a peak gust of 65 mph at 07/0825 MST.
The WYDOT sensor at Foote Creek measured sustained winds of 40 mph or higher, with a peak gust of 62 mph at 07/2200 MST.
The WYDOT sensor at Deer Creek measured sustained winds of 40 mph or higher, with a peak gust of 64 mph at 07/1615 MST.
The WYDOT sensor at Remount Road measured sustained winds of 40 mph or higher.
The WYDOT sensor at Strouss Hill measured sustained winds of 40 mph or higher, with a peak gust of 73 mph at 07/1605 MST.
The WYDOT sensor at Lone Tree measured sustained winds of 40 mph or higher, with a peak wind of 68 mph at 07/2240 MST.
The WYDOT sensor at Hynds Lodge Road measured wind gusts of 58 mph or higher, with a peak gust of 61 mph at 07/2000 MST.
The WYDOT sensor at Buford East measured wind gusts of 58 mph or higher, with a peak gust of 72 mph at 07/2311 MST.
The WYDOT sensor at Interstate 80 mile marker 353 measured sustained winds of 40 mph or higher, with a peak gust of 75 mph at 07/2150 MST.
The WYDOT sensor at Vedauwoo measured sustained winds of 40 mph or higher, with a peak gust of 64 mph at 07/2225 MST.
The WYDOT sensor at Wildcat Trail measured wind gusts of 58 mph or higher, with a peak gust of 83 mph at 07/2250 MST.
The WYDOT sensor at Wagonhound measured peak wind gusts of 59 mph.
The WYDOT sensor at Whitaker measured sustained winds of 40 mph or higher, with a peak gust of 67 mph at 08/0030 MST.
The WYDOT sensor at Bear Creek measured sustained winds of 40 mph or higher, with a peak gust of 62 mph at 08/0025 MST.
The wind sensor at the Torrington Airport measured a peak wind gust of 58 mph.
The WYDOT sensor at Arlington measured sustained winds of 40 mph or higher, with a peak gust of 62 mph at 08/1755 MST.
The WYDOT sensor at Strouss Hill measured peak wind gusts of 63 mph.
The WYDOT sensor at Cooper Cove measured sustained winds of 40 mph or higher, with a peak gust of 60 mph at 08/0505 MST.
The WYDOT sensor at Wyoming Hill measured sustained winds of 40 mph or higher, with a peak gust of 59 mph at 08/0550 MST.
The wind sensor at the pine Bluffs Airport measured sustained winds of 40 mph or higher.
The WYDOT sensor at Coleman measured peak wind gusts of 63 mph.
The WYDOT sensor at Foote Creek measured sustained winds of 40 mph or higher, with a peak gust of 58 mph at 08/2210 MST.
The WYDOT sensor at Arlington measured sustained winds of 40 mph or higher, with a peak gust of 66 mph at 09/0510 MST.
The WYDOT sensor at Wagonhound measured sustained winds of 40 mph or higher, with a peak gust of 61 mph at 09/0010 MST.
The WYDOT sensor at Bordeaux measured sustained winds of 40 mph or higher, with a peak gust of 68 mph at 09/1020 MST.
The WYDOT sensor at Foote Creek measured sustained winds of 40 mph or higher, with a peak gust of 67 mph at 09/0350 MST.
The WYDOT sensor at Cooper Cove measured sustained winds of 40 mph or higher, with a peak gust of 65 mph at 09/0105 MST.
The WYDOT sensor at Halleck Ridge measured sustained winds of 40 mph or higher, with a peak gust of 59 mph at 09/0510 MST.
The WYDOT sensor at Strouss Hill measured sustained winds of 40 mph or higher, with a peak gust of 59 mph at 09/0545 MST.
The WYDOT sensor at Interstate 80 mile marker 353 measured sustained winds of 40 mph or higher, with a peak gust of 58 mph at 09/0625 MST.
The wind sensor at the Cheyenne Airport measured a peak gust of 58 mph.
The WYDOT sensor at Lone Tree measured wind gusts of 58 mph or higher, with a peak gust of 72 mph at 09/1240 MST.
The WYDOT sensor at Otto Road measured sustained winds of 40 mph or higher, with a peak gust of 62 mph at 09/1150 MST.
The WYDOT sensor at Buford East measured sustained winds of 40 mph or higher, with a peak gust of 65 mph at 09/1306 MST.
The WYDOT sensor at Deer Creek measured sustained winds of 40 mph or higher, with a peak gust of 63 mph at 09/1225 MST.
The WYDOT sensor at Pumpkin Vine measured sustained winds of 40 mph or higher.
The WYDOT sensor at Vedauwoo measured sustained winds of 40 mph or higher, with a peak gust of 65 mph at 09/1240 MST.
The WYDOT sensor at Wildcat Trail measured wind gusts of 58 mph or higher, with a peak gust of 70 mph at 09/1455 MST.
The WYDOT sensor at Coleman measured sustained winds of 40 mph or higher, with a peak gust of 75 mph at 09/2030 MST.
The WYDOT sensor at Bear Creek measured sustained winds of 40 mph or higher, with a peak gust of 60 mph at 09/2235 MST.
The WYDOT sensor at Arlington measured sustained winds of 40 mph or higher, with a peak gust of 65 mph at 09/2240 MST.
The WYDOT sensor at Bordeaux measured sustained winds of 40 mph or higher, with a peak gust of 62 mph at 10/0015 MST.
The WYDOT sensor at Wagonhound 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: 612784, 612978, 612966, 612959, 612780, 612954, 612772, 612793, 612994, 612987, 612777, 612962, 612976, 612787, 612968, 612781, 612779, 612775, 612988, 612791, 612794, 612972, 612992, 612995, 612984, 612955, 612969, 612960, 612993, 612999, 612982, 612963, 612956, 612973, 612979, 612965, 612961, 612967, 612970, 612989, and more.