Morning brief hour of sustained winds averaging over the hour to 40 mph at Wyoming Department of Transportation sensor at Bordeaux along Interstate 25 about nine miles south of Wheatland.
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The episode as NWS CYS wrote it up.
Morning brief hour of sustained winds averaging over the hour to 40 mph at Wyoming Department of Transportation sensor at Bordeaux along Interstate 25 about nine miles south of Wheatland.
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 4, 4:30 AM MST, 1 hour 8 minutes earlier.
Area Forecast Discussion National Weather Service Cheyenne WY 430 AM MST Fri Dec 4 2020 .SHORT TERM...(Today - Saturday Night) Issued at 215 AM MST Fri Dec 4 2020 A warm & dry weekend ahead for the central Rockies w/ broad upper- level ridging remaining anchored over much of the western US. Wind continues to be a concern at Bordeaux early this morning, courtesy of a strong (4-6 mb) pressure gradient across the southern Laramie Range. Sustained winds of 35 to 40 MPH have been common throughout the night, with frequent gusts around 45 MPH. Do not anticipate we will need a High Wind Warning, but will continue to monitor trends over the next few hours. Low-level gradients are finally projected to weaken by mid-day, ending these elevated gap flows focused only on Bordeaux. Temperatures continue to trend warmer today with day- time highs in the mid/upper 50s for areas along and east of I-25 & low to mid 40s over our western zones. Saturday should be slightly cooler w/ the passage of a weak cold front, but generally speaking it will be another mild day. Dry conditions prevail. .LONG TERM...(Sunday - Thursday) Issued at 215 AM MST Fri Dec 4 2020 Warm & dry conditions will continue into Sunday beneath persistent ridging aloft. 700 millibar temperatures of +3C to +5C will likely support daytime highs approaching 60 deg F for the majority of the eastern Plains. Bordeaux may get gusty again on early Sunday AM w/ ARL-BRX MSLP gradients climbing back above 5 millibars, as well as slightly stronger 800 mb flow than we are experiencing today. This is concerning as we may have slightly higher gust potential closer to warning criteria, so this will be something for later shifts to keep an eye on. Otherwise, an uneventful weather pattern is likely to persist through Tuesday as a vigorous closes off, and begins to drift quickly southward toward the Baja Peninsula. Should not have much of an influence from the northern stream through at least the middle of the week. Highs in the 60s appear likely for our eastern zones on Tuesday and Wednesday. The models continue to suggest the passage of a mid-level short wave & associated cold front on Thu & Fri next week. This system could bring a period of strong winds to the southeast Wyoming wind corridors, as well as chances for rain/ snow depending on the exact storm track. Regardless, this may most likely be a very progressive storm system that will be fairly low- impact for our region. && .AVIATION...(For the 12Z TAFS through 12Z Saturday morning) Issued at 423 AM MST Fri Dec 4 2020 VFR conditions expected for area terminals through the forecast period as clear skies persist across the region. A few sites could see gusts to 20 kts this afternoon, primarily near KSNY and KAIA. && .FIRE WEATHER... Issued at 215 AM MST Fri Dec 4 2020 Fire weather conditions will be elevated once again this afternoon for areas along/east of I-25 with minimum RHs near 15 percent, and wind gusts approaching 25 MPH in the afternoon. Otherwise, minimal fire weather concerns are anticipated over the next few days. High temperatures will trend warmer w/ continued dry conditions through the weekend into early next week. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && SHORT TERM...CLH LONG TERM...CLH AVIATION...MB FIRE WEATHER...CLH
Hazardous Weather Outlook National Weather Service Cheyenne WY 923 AM MST Thu Dec 3 2020 WYZ106-041630- Central Laramie Range and Southwest Platte County- 923 AM MST Thu Dec 3 2020 This hazardous weather outlook is for portions of southeast Wyoming. .DAY ONE...TODAY AND TONIGHT West winds may gust as high as 50 MPH today for areas near Bordeaux along Interstate 25 between Chugwater and Wheatland. Winds could remain elevated through Friday. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY The probability for widespread hazardous weather is low. .Spotter information statement... Spotter activation will not be required. NEZ019>021-054-055-041630- Scotts Bluff County-Banner County-Morrill-Kimball County-Cheyenne- 923 AM MST Thu Dec 3 2020 This hazardous weather outlook is for southern portions of the Nebraska Panhandle. .DAY ONE...TODAY AND TONIGHT Elevated to near critical fire weather conditions are expected this afternoon with minimum relative humidities in the teens and wind gusts around 25 mph. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY Elevated to near critical fire weather conditions are expected Friday afternoon with minimum relative humidities in the teens and wind gusts around 25 mph. .Spotter information statement... Spotter activation will not be required.
Special Weather Statement National Weather Service Cheyenne WY 245 AM MST Fri Dec 4 2020 WYZ106-042100- Central Laramie Range and Southwest Platte County- Including the city of Bordeaux 245 AM MST Fri Dec 4 2020 West winds of 35 to 40 MPH with frequent gusts up to 50 MPH will persist through this morning and early afternoon for areas mainly around Bordeaux along Interstate 25 between Chugwater and Wheatland. Motorists traveling through this area are advised to use caution, especially if driving light or high profile vehicles including camping and tractor trailers. CLH
The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
Wyoming Department of Transportation sensor along Interstate 25 at Bordeaux or nine miles south of Wheatland measured the one hour average sustained winds.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2020Every state in 2020This day in weather historyWarnings in Wyoming, December 2020
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: 927846.