Sustained winds of 40 MPH were measured along Interstate 80 near Arlington for over 1 hour.
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The episode as NWS CYS wrote it up.
Sustained winds of 40 MPH were measured along Interstate 80 near Arlington for over 1 hour.
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 Oct 29, 4:33 PM MST, 4 hours 33 minutes earlier.
Area Forecast Discussion National Weather Service Cheyenne WY 533 PM MDT Fri Oct 29 2021 .SHORT TERM...(This evening through Sunday night) Issued at 144 PM MDT Fri Oct 29 2021 Tonight...Primary challenge will be the winds at Arlington and Bordeaux. Decent winds occurred overnight into this morning. With our forecast area in the wake of a passing shortwave trough aloft overnight, and with the Craig to Casper 850/700 mb height gradients strengthening somewhat, believe it would be prudent to upgrade our High Wind Watches to Warnings for Arlington and Bordeaux, despite the 700 mb winds being only around 40 knots. With the mixing and a relatively mild airmass, minimum temperatures will be relatively mild for late October. Saturday...As a shortwave trough aloft slides across eastern Montana and North Dakota, surface high pressure and a shallow cold front will slide southward across our counties, producing a cooler day, though still relatively mild. Saturday night...As the cold air deepens somewhat, and with warm air advection occurring above the cold dome, and with the lower levels becoming more saturated, it looks like areas of light rain and snow will develop mainly east of I-25, with some areas of freezing drizzle and light freezing rain possible based on projected soundings. Sunday...Shallow low level upslope east and southeast winds will prevail, along with warm air overrunning at mid levels overrunning the cold dome. Hard to say how deep the cold air will be, and where the banded precipitation will set up. For now, will continue with the highest pops near the Colorado state line, with temperatures cool enough for light snow, or a mixture of light rain and snow. Definitely colder than Saturday with widespread highs in the 30s east of I-25. Sunday night...As jet energy aloft moves overhead, overriding the cold dome at the surface, and with a saturated airmass, there will be a good chance for light snow especially near the Colorado state line. At this time, it looks like snowfall totals of 1 to 2 inches will be possible from Laramie to Cheyenne to Kimball and Sidney. .LONG TERM...(Monday through Friday) Issued at 144 PM MDT Fri Oct 29 2021 The deep upper level low currently positioned across Ohio and Tennessee Valley is expected to continue its track towards the Mid- Atlantic, before being absorbed into the main flow early Sunday Morning with a much stronger upper level low pushing eastward just north of the Great Lakes. This feature begins to set up a broad Omega Block pattern, with a near stationary upper level ridge just over the Southwest, and becomes the dominating feature for the CWA. Northwesterly flow will remain through the middle of next week, funneling much colder air, and as a result forcing daytime highs to struggle to reach over 40F. Fair amount of uncertainty in the long term, with current model guidance pushing more towards an omega block pattern, with earlier models showing much different feature and almost daily changes within the run. Nevertheless, several shortwaves are evident, effectively undercutting the ridge and bringing a chance for precipitation almost every day. Main concern is for rain and snow chances from mid to late week with some movement for the Omega Block eastward. If this latest long range solution trends more accurately, the ridge of high pressure will greatly influence the region as it extends from the Four Corners northward into the Great Plains. Went ahead and started trending POPs downward, around 5-10%, to account for this new solution. However, we will need to keep monitoring the evolution of the upper level ridge for exact timing and impacts, as we cannot rule out snow chances throughout the week. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 532 PM MDT Fri Oct 29 2021 VFR conditions are expected over the next 12 hours at all terminals. Weather should remain relatively quiet overnight. Gusts at KRWL should come down some time this evening after the sun sets. KCYS could see some gusty winds late overnight and into the morning hours with gusts up to 25kts possible. Tomorrow, expect increasing clouds as a cold front approaches the area. All terminals could also see some gusty winds tomorrow afternoon. && .FIRE WEATHER... Issued at 144 PM MDT Fri Oct 29 2021 No concerns based on projected winds and humidities. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...High Wind Warning until 9 AM MDT Saturday for WYZ106-110. NE...None. && SHORT TERM...RUBIN LONG TERM...MD AVIATION...SF FIRE WEATHER...RUBIN
Hazardous Weather Outlook National Weather Service Cheyenne WY 203 PM MDT Fri Oct 29 2021 NEZ002-003-019>021-054-055-095-096-WYZ101>105-107>109-111>119- 302015- Dawes County-Box Butte County-Scotts Bluff County-Banner County- Morrill County-Kimball County-Cheyenne County- Northern Sioux County-Southern Sioux County- 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- South Laramie Range-South Laramie Range Foothills- Central Laramie County-East Laramie County- 203 PM MDT Fri Oct 29 2021 This hazardous weather outlook is for portions of panhandle 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 rain and snow chances with breezy conditions and much colder temperatures beginning Saturday night and continuing through Wednesday. .Spotter information statement... Spotter activation will not be needed. WYZ106-110-302015- Central Laramie Range and Southwest Platte County- North Snowy Range Foothills- 203 PM MDT Fri Oct 29 2021 This hazardous weather outlook is for portions of south central Wyoming and southeast Wyoming. .DAY ONE...THIS AFTERNOON AND TONIGHT A High Wind Warning is in effect for tonight for west winds of 35 to 45 mph with gusts to 60 mph. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY The High Wind Warning continues until 9 AM Saturday. Widespread rain and snow chances with breezy conditions and much colder temperatures beginning Saturday night and continuing through Wednesday. .Spotter information statement... Spotter activation will not be needed. Rubin
The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
WYDOT mesonet station KARL - Arlington along Interstate 80 measured 1 hour of 40 MPH sustained winds. Maximum wind gust during this period was 52 MPH.
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, October 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: 983845.