A brief period of strong gap winds developed between Chugwater and Wheatland, and near Elk Mountain and Arlington.
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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 brief period of strong gap winds developed between Chugwater and Wheatland, and near Elk Mountain and Arlington.
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 5, 2:46 AM MST, 44 minutes earlier.
Area Forecast Discussion National Weather Service Cheyenne WY 246 AM MST Tue Dec 5 2017 .SHORT TERM...(Today through Thursday) Issued at 230 AM MST Tue Dec 5 2017 Clear to partly cloudy skies over the CWA with an upper trough axis moving east of the area. Northwesterly flow aloft establishing over the CWA and this will hold for the next few days, becoming northerly Wed as the next upper shortwave dives south down the high plains. Main concern will be with pretty healthy winds that will occur mainly over the plains especially Wednesday as fast mid level flow persists over the region. 850H winds around 30 kt progged over the NE Panhandle Wed afternoon and would not be surprised to see some gusts over 40 kt. Should stay below high wind levels however. A clipper-type system may bring a few snow showers to the CWA Thursday as it scoots across. .LONG TERM...(Thursday night through Monday) Issued at 245 AM MST Tue Dec 5 2017 00Z medium range models/ensembles prog a highly amplified flow with a stout upper ridge over the Great Basin and deep upper trough from the Great Lakes to the Gulf Coast to begin the forecast period. The large scale pattern will change little, with a dry northwesterly flow aloft prevailing. There will be windy periods Thursday night through Saturday with the presence of a strong northwest upper jet, then breezy Sunday and Monday. Despite a few weak frontal passages, temperatures will average 5-10 degrees above seasonal normals. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 230 AM MST Tue Dec 5 2017 VFR with scattered mid/clouds. Sustained W-NW winds 5-15 kt early this morning increase to 20-25 kt with gusts to 35 kt after 15Z. && .FIRE WEATHER... Issued at 230 AM MST Tue Dec 5 2017 No fire weather concerns seen for the rest of the week with cool temperatures and humidities remaining above critical levels. There will be some windiness over the next couple days, mainly in the afternoons. Next cold front will pass across tonight bringing another chilly day for Wednesday. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && SHORT TERM...RE LONG TERM...MAJ AVIATION...MAJ FIRE WEATHER...RE
Hazardous Weather Outlook National Weather Service Cheyenne WY 202 PM MST Mon Dec 4 2017 NEZ002-003-019>021-054-055-095-096-052115- Dawes-Box Butte-Scotts Bluff-Banner-Morrill-Kimball-Cheyenne- North Sioux-South Sioux- 202 PM MST Mon Dec 4 2017 This hazardous weather outlook is for portions of western Nebraska. .DAY ONE...THIS AFTERNOON AND TONIGHT Very cold temperatures tonight with overnight lows in the low to mid teens. Windchill temperatures expected to fall to single digits above zero across the panhandle tonight. Dress warm and keep exposed skin covered if outside tonight to avoid any cold related injuries. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY Expect gusty northwest winds to continue in the Nebraska Panhandle each day with gusts in excess of 40 mph each day. .Spotter information statement... Spotter activation will not be needed tonight. WYZ101>119-052115- 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- 202 PM MST Mon Dec 4 2017 This hazardous weather outlook is for portions of east central Wyoming...south central Wyoming and southeast Wyoming. .DAY ONE...THIS AFTERNOON AND TONIGHT Very cold temperatures tonight with overnight lows in the low to mid teens. Windchill temperatures expected to fall to single digits above zero across the panhandle tonight. Dress warm and keep exposed skin covered if outside tonight to avoid any cold related injuries. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY Expect gusty northwest winds to continue in the Nebraska Panhandle each day with gusts in excess of 50 mph each day. Could see very strong winds leading to increased blow off or blowover risk in the wind prone areas of southeast Wyoming Thursday into Friday this upcoming week. .Spotter information statement... Spotter activation will not be needed tonight.
Special Weather Statement National Weather Service Cheyenne WY 237 AM MST Tue Dec 5 2017 WYZ110-051300- North Snowy Range Foothills- Including the cities of Arlington and Elk Mountain 237 AM MST Tue Dec 5 2017 Locally gusty west winds will occur along Interstate 80 around the Arlington area early this morning. Some gusts over 45 mph are expected. These winds will likely produce some areas of blowing and drifting snow. Motorists are urged to drive with extra caution as some slick conditions may also exist.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
330 AM MST TUE DEC 05 2017
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0330 AM HIGH SUST WINDS ARLINGTON 41.59N 106.21W
12/05/2017 M48 MPH CARBON WY DEPT OF HIGHWAYS
SUSTAINED 40+ MPH SINCE 230 AM.
&&
MJAMSKIThe national radar mosaic for the moment the first event began.
5 high wind. Local standard time, as filed.
The WYDOT sensor at Arlington measured sustained winds of 40 mph or higher, with a peak gust of 63 mph at 5/0720 MST.
The WYDOT sensor at Bordeaux measured sustained winds of 40 mph or higher, with a peak gust of 63 mph at 5/0725 MST.
The WYDOT sensor at Foote Creek measured sustained winds of 40 mph or higher.
The WYDOT sensor at Halleck Ridge measured sustained winds of 40 mph or higher.
The WYDOT sensor at County Road 402 measured peak wind gusts of 58 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2017Every state in 2017This day in weather historyWarnings in Wyoming, December 2017
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: 730750, 730749, 730753, 730754, 730751.