Alert archive / Wyoming / Freeze Warnings in 2021
Freeze Warning 2, NWS Cheyenne, WY
NWS Cheyenne, WY issued this freeze warning at Sep 20, 2021, 1:26 PM MDT for 5 counties in Wyoming. It took effect at Sep 21, 2021, 1:00 AM MDT. It was in force for 7 hr. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Sep 20, 2021, 1:26 PM MDT (19:26 UTC)
- In effect from
- Sep 21, 2021, 1:00 AM MDT
- Expired
- Sep 21, 2021, 8:00 AM MDT
- In force
- 7 hr
- Issued by
- NWS Cheyenne, WY
Counties Albany County, WY, Carbon County, WY, Converse County, WY, Laramie County, WY, Platte County, WY
The radar
The Cheyenne radar (KCYS), 109 km from the middle of the area, began a volume at 19:29 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Riverton, WY (KRIW), launched 12:00Z, 7.4 hours before the alert went out and 264 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 2 J/kg
- Mixed-layer CIN
- -57 J/kg
- Mixed-layer LCL
- 1254 m above ground
- 0-6 km bulk shear
- 49 kt
- 0-1 km storm-relative helicity
- 25 m²/s²
- 0-3 km storm-relative helicity
- 25 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
038 WWUS75 KCYS 201926 NPWCYS URGENT - WEATHER MESSAGE National Weather Service Cheyenne WY 126 PM MDT Mon Sep 20 2021 WYZ103>105-109>111-113-115-116-211400- /O.UPG.KCYS.FZ.A.0001.210921T0700Z-210921T1400Z/ /O.NEW.KCYS.FZ.W.0002.210921T0700Z-210921T1400Z/ North Laramie Range-Ferris/Seminoe/Shirley Mountains- Shirley Basin-Central Carbon County-North Snowy Range Foothills- Southwest Carbon County-Upper North Platte River Basin- Laramie Valley-South Laramie Range- Including the cities of Garrett, Esterbrook, Seminoe Dam, Medicine Bow, Shirley Basin, Rawlins, Arlington, Elk Mountain, Baggs, Saratoga, Encampment, Laramie, Bosler, Buford, Pumpkin Vine, and Vedauwoo 126 PM MDT Mon Sep 20 2021 ...FREEZE WARNING IN EFFECT FROM 1 AM TO 8 AM MDT TUESDAY... * WHAT...Sub-freezing temperatures as low as 29 expected. * WHERE...North Laramie Range, Ferris/Seminoe/Shirley Mountains, Shirley Basin, Central Carbon County, North Snowy Range Foothills, Southwest Carbon County, Upper North Platte River Basin, Laramie Valley and South Laramie Range. * WHEN...From 1 AM to 8 AM MDT Tuesday. * IMPACTS...Frost and freeze conditions will kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. If recreating outdoors, be sure to have warm enough clothing for freezing temperatures. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. To prevent freezing and possible bursting of outdoor water pipes they should be wrapped, drained, or allowed to drip slowly. Those that have in-ground sprinkler systems should drain them and cover above- ground pipes to protect them from freezing. && $$ WYZ106-117>119-211400- /O.NEW.KCYS.FR.Y.0001.210921T0700Z-210921T1400Z/ Central Laramie Range and Southwest Platte County- South Laramie Range Foothills-Central Laramie County- East Laramie County- Including the cities of Bordeaux, Whitaker, Federal, Horse Creek, Cheyenne, and Pine Bluffs 126 PM MDT Mon Sep 20 2021 ...FROST ADVISORY IN EFFECT FROM 1 AM TO 8 AM MDT TUESDAY... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Central Laramie Range and Southwest Platte County, South Laramie Range Foothills, Central Laramie County and East Laramie County. * WHEN...From 1 AM to 8 AM MDT Tuesday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. && $$
The office that day
Everything else NWS Cheyenne, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 20, 1:26 PM MDT | Frost Advisory | CYS | Albany, Laramie, Platte | 19 hr |
Nearby
Freeze Warnings in Wyoming, 2021Every freeze warning in 2021
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.