Another high wind event was felt across the southern Laramie Range in southeast Wyoming, particularly the foothills, Central Laramie Range, and Central Laramie County. E.
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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.
Another high wind event was felt across the southern Laramie Range in southeast Wyoming, particularly the foothills, Central Laramie Range, and Central Laramie County. Highest wind gusts were measured by a Union Pacific Railroad sensor west-southwest of F.E. Warren Air Force Base while upper 50 mph gust measured at other sites.
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 Feb 21, 10:23 PM MST, 2 hours 27 minutes earlier.
Area Forecast Discussion...UPDATED National Weather Service Cheyenne WY 1023 PM MST Fri Feb 21 2020 .SHORT TERM...(Tonight & Saturday) Issued at 224 PM MST Fri Feb 21 2020 The main forecast concern/highlight over the next 12-24 hours will be the potential for strong winds in the wind prone areas of south east Wyoming, including BRX as well as the I-80 Summit between LAR and CYS. Low-level gradients are likely to intensify this evening/ overnight in response to height falls associated w/ a vigorous mid level disturbance tracking across the region. A strong (1030+ hpa) surface high over western Wyoming will contribute to a substantial W-E pressure gradient along the Laramie Range, likely on the order of 4-6 mb. A few differences to note from the sporadic gusts to 55 MPH last night. First, the flow aloft is significantly stronger w/ the GFS showing a wide swath of 55 knot H7-H8 flow in place across the central/southern Laramie Range. Subsidence should be strong as well given the favorable track of the short wave. In addition, the potential for mountain-wave activity appears to be high. Models do show a distinct kink in mid-level height contours, and vertical X- sections of omega & potential temperature fields suggest potential breaking waves. The mountain top inversion is clear over BRX w/ 50 knots just off the surface in the models. Lower confidence for the I-80 corridor, but it should still get very gusty regardless given impressive subsidence as well as the low-level gradients. If these locations do not hit 60+ MPH wind gusts overnight, it may still be a possibility through the day on Saturday w/ low-lvl mixing in the mid/late morning. High Wind Warnings have been posted, and will be valid from 8 PM tonight until 2 PM MST Saturday. ARL should remain below warning criteria this period, given the strongest flow aloft being displaced to the east. .LONG TERM...(Sunday - Friday) Issued at 325 AM MST Fri Feb 21 2020 A 500mb upper level low and its associated trough will propagate from the west coast over to the four corners area by early Sunday morning. This upper level low will become cut off from the main upper level jet support. The northern stream of jet energy looks to be fairly progressive, and it maintains its trajectory over the northern Rocky mountains from west to east quickly. Very little moisture will be associated with the northern jet energy over our forecast area. The medium range guidance from both the ECMWF and the GFS point to a scenario where the likely outcome has the cut off low maintain a near due east heading from the four corners region, propagating over southern Colorado. Lee cyclogenesis does take place once this cutoff upper level low is east of the Rocky Mountains. However, the model guidance is strongly hinting that the surface low associated with the cutoff upper level low at 500mb will develop in south central to extreme southeast Colorado. Wrap around moisture with the developing surface may make its way north up to the I-80 corridor near our forecast area as the surface low deepens from Colorado to the southwestern Kansas/Oklahoma Panhandle. Low snow totals are likely with this weather setup for our area in the 1-2 inch range. Temperatures will likely be in the low to mid 40s in the western Nebraska Panhandle by the time the cold front arrives Sunday. With the warmer surface air in that region, the start of precipitation will likely be rain and then switch over to snow after the cold front moves through the entire forecast area. Temperatures should stay closer to the freezing mark in Southeast WY because of the higher elevation and closer proximity to the cold FROPA that morning. The weather system will quickly exit the region by Sunday night before the arrival of the next quickly approaching weather system on Monday. The active weather pattern looks to continue on Monday and Tuesday with another weather system providing the area with perhaps another shot of accumulating light snow in spots. Additional surges of cold air will spread over the region due to the passing front on Monday into Tuesday, and this will keep temps cold and below average for the region. Models have backed off on the possibility of continued northwest flow aloft from Monday to Wednesday. The shorter duration of time and lower amount of moisture compared to previous snow events in the mountains will likely only force the need for a possible weather advisory headline in the higher terrain. It will also be windy for the I-25/I-80 corridor in the wind prone areas early Monday into the afternoon. The wind gradients really begin to tighten on Monday and Monday night. 850mb gradients are 55-75 knots currently on Monday for CAG to BRX. Additionally they are 55-65 knots from CAG to ARL at the 850mb level. Blow over risks may be possible early Monday into Monday afternoon. The remainder of the week looks to see upper level ridging aloft. This will allow the area to see a more tranquil weather pattern for a few days. Surface temperatures will slowly rise over the latter part of the week back up to seasonal averages for the time period. Several areas will see temperatures near 50 degrees and higher in the Nebraska Panhandle and North Platte River Valley by Friday. Definitely something to look forward to after a cold start to next week with the passing weather systems and surges of cold air. High winds look to make a return by the middle to late part of next week. We will keep an eye on this in the event that the chances of strong winds becomes more apparent as the time draws && .AVIATION...(For the 06Z TAFS through 06Z Saturday night) Issued at 1020 PM MST Fri Feb 21 2020 Wyoming TAFS...VFR. Wind gusts to 32 knots at Rawlins, Laramie and Cheyenne until 01Z. Nebraska TAFS...VFR. Wind gusts to 25 knots at Alliance and Sidney from 16Z to 01Z. && .FIRE WEATHER... Issued at 325 AM MST Fri Feb 21 2020 Near critical fire weather conditions expected today with low humidities and warmer than normal temperatures along the CO-WY border under a ridge of high pressure. Humidites are expected to rise beginning Saturday ahead of several rounds of snow in the next week. More dry weather in store for the region next weekend under another ridge of high pressure. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...High Wind Warning until 2 PM MST Saturday for WYZ106-116-117. NE...None. && SHORT TERM...CLH LONG TERM...AB AVIATION...RUBIN FIRE WEATHER...AB
Hazardous Weather Outlook National Weather Service Cheyenne WY 335 PM MST Fri Feb 21 2020 WYZ106-110-116-117-222245- Central Laramie Range and Southwest Platte County- North Snowy Range Foothills-South Laramie Range- South Laramie Range Foothills- 335 PM MST Fri Feb 21 2020 This hazardous weather outlook is for portions of south central Wyoming and southeast Wyoming. .DAY ONE...THIS AFTERNOON AND TONIGHT Strong wind gusts up to 65 MPH will be possible in the wind prone areas of southeast Wyoming tonight through Saturday. Please refer to High Wind Warnings for more details. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY High winds are possible again on Sunday night and Monday. .Spotter information statement... Spotter activation will not be needed. WYZ107-118-222245- East Platte County-Central Laramie County- 335 PM MST Fri Feb 21 2020 This hazardous weather outlook is for portions of southeast Wyoming. .DAY ONE...THIS AFTERNOON AND TONIGHT Mountain waves may result in brief periods of strong winds spreading into the Interstate 25 corridor overnight through Saturday morning. Wind gusts in excess of 50 MPH are possible. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY Widespread strong winds will be possible on Monday. .Spotter information statement... Spotter activation will not be needed. WYZ112-114-222245- Sierra Madre Range-Snowy Range- 335 PM MST Fri Feb 21 2020 This hazardous weather outlook is for portions of south central Wyoming. .DAY ONE...THIS AFTERNOON AND TONIGHT No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY Accumulating mountain snow is possible on Monday and Tuesday. .Spotter information statement... Spotter activation will not be needed. NEZ002-003-019>021-054-055-095-096-WYZ101>105-108-109-111-113-115- 119-222245- 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-Goshen County- Central Carbon County-Southwest Carbon County- Upper North Platte River Basin-Laramie Valley-East Laramie County- 335 PM MST Fri Feb 21 2020 This hazardous weather outlook is for portions of western Nebraska...east central Wyoming...south central Wyoming and southeast Wyoming. .DAY ONE...THIS AFTERNOON AND TONIGHT No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY Widespread strong winds will be possible on Monday. .Spotter information statement... Spotter activation will not be needed.
The national radar mosaic for the moment the first event began.
3 high wind. Local standard time, as filed.
Wyoming Department of Transportation site at Bordeaux or nine miles south of Wheatland measured the reported wind gust.
Union Pacific Railroad site at Emkay located eleven miles west-southwest of Warren Air Force Base measured the reported wind gust.
Wyoming Department of Transportation sensor along Interstate 25 south of Chugwater at Bear Creek measured the reported wind gust.
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, February 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: 870155, 870156, 870998.