Alert archive / Wyoming / Flash Flood Watches in 2021
Flash Flood Watch 2, NWS Cheyenne, WY
NWS Cheyenne, WY issued this flash flood watch at Aug 2, 2021, 1:54 PM MDT for 4 counties in Wyoming. It took effect at Aug 3, 2021, 12:00 PM MDT. It was in force for 10 hr.
The area
The counties it named.
The facts
- Issued
- Aug 2, 2021, 1:54 PM MDT (19:54 UTC)
- In effect from
- Aug 3, 2021, 12:00 PM MDT
- Expired
- Aug 3, 2021, 9:32 PM MDT
- In force
- 10 hr
- Issued by
- NWS Cheyenne, WY
- Flood severity
- None
Counties Albany County, WY, Carbon County, WY, Converse County, WY, Platte County, WY
The radar
The Cheyenne radar (KCYS), 134 km from the middle of the area, began a volume at 19:56 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, 7.9 hours before the alert went out and 239 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2380 m above ground
- 0-6 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 5 m²/s²
- 0-3 km storm-relative helicity
- 14 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
960 WGUS65 KCYS 021954 FFACYS URGENT - IMMEDIATE BROADCAST REQUESTED Flood Watch National Weather Service Cheyenne WY 154 PM MDT Mon Aug 2 2021 .Monsoonal moisture will spread east into portions of south central and southeast Wyoming Tuesday. Showers and thunderstorms will develop during the late morning, increasing in coverage and intensity in the afternoon. Some of the showers and thunderstorms will be capable of producing rainfall up to an inch per hour. Heavy rainfall over recently burned areas will increase the risk for flash flooding. WYZ103-105-110-112>115-031100- /O.NEW.KCYS.FF.A.0002.210803T1800Z-210804T0600Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ North Laramie Range-Shirley Basin-North Snowy Range Foothills-Sierra Madre Range-Upper North Platte River Basin-Snowy Range-Laramie Valley- Including the cities of Encampment, Albany, Esterbrook, Saratoga, Arlington, Garrett, Laramie, Elk Mountain, Medicine Bow, Shirley Basin, Centennial, and Bosler 154 PM MDT Mon Aug 2 2021 ...FLASH FLOOD WATCH IN EFFECT FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING... The National Weather Service in Cheyenne has issued a * Flash Flood Watch for portions of south central Wyoming and southeast Wyoming, including the following areas, in south central Wyoming, North Snowy Range Foothills, Shirley Basin, Sierra Madre Range, Snowy Range and Upper North Platte River Basin. In southeast Wyoming, Laramie Valley and North Laramie Range. * From Tuesday afternoon through Tuesday evening. * Heavy rainfall from showers and thunderstorms will increase the threat for flash flooding in the watch area. * Recently burned areas will be more susceptible to flash flooding, especially in and around the Mullen Burn Scar. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ Jamski
3 follow-up statements
482 WGUS65 KCYS 031221 FFACYS Flood Watch National Weather Service Cheyenne WY 621 AM MDT Tue Aug 3 2021 .Monsoonal moisture will spread east into portions of south central and southeast Wyoming this afternoon. Showers and thunderstorms will develop during the late morning, increasing in coverage and intensity in the afternoon. Some of the showers and thunderstorms will be capable of producing rainfall up to an inch per hour. Heavy rainfall over recently burned areas will increase the risk for flash flooding. WYZ103-105-110-112>115-032030- /O.CON.KCYS.FF.A.0002.210803T1800Z-210804T0600Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ North Laramie Range-Shirley Basin-North Snowy Range Foothills-Sierra Madre Range-Upper North Platte River Basin-Snowy Range-Laramie Valley- Including the cities of Encampment, Albany, Esterbrook, Saratoga, Arlington, Garrett, Laramie, Elk Mountain, Medicine Bow, Shirley Basin, Centennial, and Bosler 621 AM MDT Tue Aug 3 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT FROM NOON MDT TODAY THROUGH THIS EVENING... The Flash Flood Watch continues for * Portions of south central Wyoming and southeast Wyoming, including the following areas, in south central Wyoming, North Snowy Range Foothills, Shirley Basin, Sierra Madre Range, Snowy Range and Upper North Platte River Basin. In southeast Wyoming, Laramie Valley and North Laramie Range. * From Noon MDT today through this evening. * Heavy rainfall from showers and thunderstorms will increase the threat for flash flooding in the watch area. * Recently burned areas will be more susceptible to flash flooding, especially in and around the Mullen Burn Scar. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ Claycomb
961 WGUS65 KCYS 031820 FFACYS Flood Watch National Weather Service Cheyenne WY 1220 PM MDT Tue Aug 3 2021 .Monsoonal moisture will spread east into portions of south central and southeast Wyoming this afternoon. Showers and thunderstorms have developed late this morning and expected to increase in coverage and intensity this afternoon. Some of the showers and thunderstorms will be capable of producing rainfall up to an inch per hour. Heavy rainfall over recently burned areas will increase the risk for flash flooding. WYZ103-105-110-112>115-040600- /O.CON.KCYS.FF.A.0002.000000T0000Z-210804T0600Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ North Laramie Range-Shirley Basin-North Snowy Range Foothills-Sierra Madre Range-Upper North Platte River Basin-Snowy Range-Laramie Valley- Including the cities of Encampment, Albany, Esterbrook, Saratoga, Arlington, Garrett, Laramie, Elk Mountain, Medicine Bow, Shirley Basin, Centennial, and Bosler 1220 PM MDT Tue Aug 3 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL MIDNIGHT MDT TONIGHT... The Flash Flood Watch continues for * Portions of south central Wyoming and southeast Wyoming, including the following areas, in south central Wyoming, North Snowy Range Foothills, Shirley Basin, Sierra Madre Range, Snowy Range and Upper North Platte River Basin. In southeast Wyoming, Laramie Valley and North Laramie Range. * Until Midnight MDT tonight. * Heavy rainfall from showers and thunderstorms will increase the threat for flash flooding in the watch area. * Recently burned areas will be more susceptible to flash flooding, especially in and around the Mullen Burn Scar. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ Brothers
024 WGUS65 KCYS 040332 FFACYS Flood Watch National Weather Service Cheyenne WY 932 PM MDT Tue Aug 3 2021 WYZ103-105-110-112>115-040445- /O.CAN.KCYS.FF.A.0002.000000T0000Z-210804T0600Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ North Laramie Range-Shirley Basin-North Snowy Range Foothills-Sierra Madre Range-Upper North Platte River Basin-Snowy Range-Laramie Valley- Including the cities of Encampment, Albany, Esterbrook, Saratoga, Arlington, Garrett, Laramie, Elk Mountain, Medicine Bow, Shirley Basin, Centennial, and Bosler 932 PM MDT Tue Aug 3 2021 ...FLASH FLOOD WATCH IS CANCELLED... The Flash Flood Watch for portions of south central Wyoming and southeast Wyoming, including the following areas, in south central Wyoming, North Snowy Range Foothills, Shirley Basin, Sierra Madre Range, Snowy Range and Upper North Platte River Basin. In southeast Wyoming, Laramie Valley and North Laramie Range has been cancelled. Flooding is no longer expected to pose a threat. Please continue to heed remaining road closures. Scattered showers, producing light to moderate rain at times, will continue to decrease in areal coverage the rest of the evening. $$ Rubin
The office that day
Everything else NWS Cheyenne, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 2, 4:20 PM MDT | Special Weather Statement | CYS | 40 min | |
| Aug 2, 4:37 PM MDT | Areal Flood Advisory | CYS | Albany | 3 hr |
Nearby
Flash Flood Watches in Wyoming, 2021Every flash flood watch 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.