Localized high winds were measured by the Wyoming Department of Transportation sensor at Arlington along Interstate 80 the morning of the 8th. Peak wind gust measured was 65 mph.
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Localized high winds were measured by the Wyoming Department of Transportation sensor at Arlington along Interstate 80 the morning of the 8th. Peak wind gust measured was 65 mph.
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 May 8, 2:57 AM MST, 1 hour 29 minutes earlier.
Area Forecast Discussion National Weather Service Cheyenne WY 357 AM MDT Sat May 8 2021 .SHORT TERM...(Today - Sunday Night) Issued at 249 AM MDT Sat May 8 2021 A small window of opportunity early this morning for 60+ MPH gusts near Arlington/Elk Mountain as the 700 hpa CAG-CPR gradient climbs to near 60 meters after 09z in advance of a surface cold front now moving into western Carbon County. Observed gusts have remained at or below 50 MPH so far, but trends will need to be monitored quite closely over the next few hours as a short-fused High Wind Warning may be required. Windy for most areas today w/ temperatures likely falling post-fropa prior to peak heating. 35+ knots of 700 mb flow should support occasional gusts to 50 MPH given the very steep low and mid level lapse rates. Isolated to widely scattered showers do appear possible today & tonight as the mid-level short wave sweeps across the area. Precipitation chances are likely to be on the up- tick again by Sunday night as a vigorous upper-level trough begins to dig south into the Great Basin. Temperatures should trend lower on Sunday with highs struggling to break 50 deg F for areas along/ west of I-25. .LONG TERM...(Monday - Friday) Issued at 249 AM MDT Sat May 8 2021 The primary focus in the extended forecast period is the potential for accumulating snow across parts of the area. The aforementioned short wave will continue digging into the 4 Corners region through Tuesday. A prolonged period of moist low-level upslope will likely result from this slow moving system, contributing to a good chance for widespread precipitation over the central high plains. Biggest challenge for this event will be snow levels w/ tricky temperature profiles in this flow regime. The models (GFS/ECM/NAM) are in very good agreement with 700 mb temperatures colder than -5 deg C after 00z Monday which leads to higher confidence in snow levels down to around 5500 feet or so. Ensemble guidance continues to suggest the widest of QPF ranges, so it is much too early to speculate on snow accumulations. Nonetheless, several inches of heavy wet snow could fall at or above 5500 feet elevation from Sunday night through Tue morning. Stay tuned! && .AVIATION...(For the 06Z TAFS through 06Z Saturday night) Issued at 1151 PM MDT Fri May 7 2021 VFR conditions currently at area terminals with passing mid-level clouds. Will need to monitor the potential development for patchy fog and reduced visibility across the NE Panhandle early this morning, however guidance suggests any lowering in flight conditions should be brief. Otherwise, gusty west to northwest winds will increase throughout the late morning and afternoon. && .FIRE WEATHER... Issued at 249 AM MDT Sat May 8 2021 Fire weather concerns will be low through early next week with the anticipation of cooler temperatures along with widespread rain and snow. && .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 1053 PM MDT Fri May 7 2021 NEZ002-003-021-055-095-WYZ101>106-109>117-082130- Dawes County-Box Butte County-Morrill County-Cheyenne County- Northern Sioux County-Converse County Lower Elevations- Niobrara County-North Laramie Range- Ferris/Seminoe/Shirley Mountains-Shirley Basin- Central Laramie Range and Southwest Platte 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- 1053 PM MDT Fri May 7 2021 This hazardous weather outlook is for portions of panhandle 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...SATURDAY THROUGH THURSDAY Sunday through Tuesday will be colder. There will also be scattered to numerous snow showers at higher elevations late Sunday with snow levels dropping to near 5500 feet Monday afternoon and evening. Stay tuned for more updates through the weekend on this snow potential next Monday and early Tuesday. .Spotter information statement... NEZ019-020-054-096-WYZ107-108-118-119-082130- Scotts Bluff County-Banner County-Kimball County- Southern Sioux County-East Platte County-Goshen County- Central Laramie County-East Laramie County- 1053 PM MDT Fri May 7 2021 This hazardous weather outlook is for portions of panhandle Nebraska and southeast Wyoming. .DAY ONE...TONIGHT No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY Sunday through Tuesday will be colder. There will also be scattered to numerous snow showers at higher elevations late Sunday with snow levels dropping to near 5500 feet Monday afternoon and evening. Stay tuned for more updates through the weekend on this snow potential next Monday and early Tuesday. .Spotter information statement...
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
524 AM MDT SAT MAY 8 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0442 AM HIGH SUST WINDS 1 NNW ARLINGTON 41.60N 106.21W
05/08/2021 M41 MPH CARBON WY DEPT OF HIGHWAYS
MESONET STATION KARL ARLINGTON ALONG
INTERSTATE 80 (WYDOT). 1 HOUR AVERAGE
SUSTAINED WIND SPEED. MAXIMUM GUST OF 55 MPH
DURING THIS PERIOD.
&&
MBThe national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
Localized high winds were measured by the Wyoming Department of Transportation sensor at Arlington along Interstate 80.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2021Every state in 2021This day in weather historyWarnings in Wyoming, May 2021
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: 949330.