Alert archive / Wyoming / Red Flag Warnings in 2021
Red Flag Warning 15, NWS Riverton, WY
NWS Riverton, WY issued this red flag warning at Aug 24, 2021, 12:56 PM MDT for 9 counties in Wyoming. It took effect at Aug 25, 2021, 12:00 PM MDT. It was in force for 8 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
- Aug 24, 2021, 12:56 PM MDT (18:56 UTC)
- In effect from
- Aug 25, 2021, 12:00 PM MDT
- Expired
- Aug 25, 2021, 8:00 PM MDT
- In force
- 8 hr
- Issued by
- NWS Riverton, WY
Counties Fremont County, WY, Hot Springs County, WY, Johnson County, WY, Lincoln County, WY, Natrona County, WY, Sublette County, WY, Sweetwater County, WY, Uinta County, WY, Washakie County, WY
The radar
The Riverton/Lander radar (KRIW), 29 km from the middle of the area, began a volume at 18:57 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, 6.9 hours before the alert went out and 34 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
- 3669 m above ground
- 0-6 km bulk shear
- 50 kt
- 0-1 km storm-relative helicity
- 121 m²/s²
- 0-3 km storm-relative helicity
- 193 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
255 WWUS85 KRIW 241856 RFWRIW URGENT - FIRE WEATHER MESSAGE National Weather Service Riverton WY 1256 PM MDT Tue Aug 24 2021 WYZ277>279-289-251130- /O.UPG.KRIW.FW.A.0007.210825T1800Z-210826T0200Z/ /O.NEW.KRIW.FW.W.0015.210825T1800Z-210826T0200Z/ Lincoln and Uinta Counties/Lower Elevations- Upper Green River Basin/Rock Springs BLM- Sweetwater County/Rock Springs BLM/Flaming Gorge NRA- Granite/Green/Ferris/Rattlesnake Mountains- 1256 PM MDT Tue Aug 24 2021 ...RED FLAG WARNING IN EFFECT FROM NOON TO 8 PM MDT WEDNESDAY... The National Weather Service in Riverton has issued a Red Flag Warning, which is in effect from noon to 8 PM MDT Wednesday. the Fire Weather Watch is no longer in effect. * IMPACTS: Low Humidities and Strong Gusty Winds will create erratic fire behavior with any new fire starts. * AFFECTED AREA: In Central WY Fire Zone....289. In Southwest WY Fire Zones...277...279. In West Central WY Fire Zone....278. * COUNTIES AFFECTED: In Central WY...Fremont...Natrona. In Southwest WY...Sweetwater...Uinta. In West Central WY...Lincoln...Sublette. * WIND: Southwest 15 to 25 mph with gusts up to 45 mph. * HUMIDITY: As low as 12 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ WYZ283-251130- /O.UPG.KRIW.FW.A.0007.210825T1800Z-210826T0200Z/ /O.NEW.KRIW.FW.W.0015.210825T1800Z-210826T0200Z/ Upper Wind River Basin/Wind River Basin- 1256 PM MDT Tue Aug 24 2021 ...RED FLAG WARNING IN EFFECT FROM NOON TO 8 PM MDT WEDNESDAY... The National Weather Service in Riverton has issued a Red Flag Warning, which is in effect from noon to 8 PM MDT Wednesday. the Fire Weather Watch is no longer in effect. * IMPACTS: Low Humidities and Strong Gusty Winds will create erratic fire behavior with any new fire starts. * AFFECTED AREA: In Central WY...Fire Weather Zone 283. * COUNTIES AFFECTED: In Central WY...Fremont. * WIND: Southwest 10 to 20 mph with gusts up to 40 mph. * HUMIDITY: As low as 11 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ WYZ280-281-285-300-251130- /O.UPG.KRIW.FW.A.0007.210825T1800Z-210826T0200Z/ /O.NEW.KRIW.FW.W.0015.210825T1800Z-210826T0200Z/ Natrona County/Casper BLM-Johnson County/Casper BLM- South Bighorn Mountains-Casper Mountain- 1256 PM MDT Tue Aug 24 2021 ...RED FLAG WARNING IN EFFECT FROM NOON TO 8 PM MDT WEDNESDAY... The National Weather Service in Riverton has issued a Red Flag Warning, which is in effect from noon to 8 PM MDT Wednesday. the Fire Weather Watch is no longer in effect. * IMPACTS: Low Humidities and Strong Gusty Winds will create erratic fire behavior with any new fire starts. * AFFECTED AREA: In Central WY Fire Zones...280...285...300. In North Central WY Fire Zone....281. * COUNTIES AFFECTED: In Central WY...Fremont...Natrona. In North Central WY...Hot Springs...Johnson...Washakie. * WIND: Southwest 10 to 20 mph with gusts up to 35 mph. * HUMIDITY: As low as 11 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ 21
3 follow-up statements
658 WWUS85 KRIW 250945 RFWRIW URGENT - FIRE WEATHER MESSAGE National Weather Service Riverton WY 345 AM MDT Wed Aug 25 2021 WYZ277>279-289-260200- /O.CON.KRIW.FW.W.0015.210825T1800Z-210826T0200Z/ Lincoln and Uinta Counties/Lower Elevations- Upper Green River Basin/Rock Springs BLM- Sweetwater County/Rock Springs BLM/Flaming Gorge NRA- Granite/Green/Ferris/Rattlesnake Mountains- 345 AM MDT Wed Aug 25 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM NOON TODAY TO 8 PM MDT THIS EVENING... * IMPACTS: Low Humidities and Strong Gusty Winds will create erratic fire behavior and new fire starts. * AFFECTED AREA: In Central WY Fire Zone....289. In Southwest WY Fire Zones...277...279. In West Central WY Fire Zone....278. * COUNTIES AFFECTED: In Central WY...Fremont...Natrona. In Southwest WY...Sweetwater...Uinta. In West Central WY...Lincoln...Sublette. * WIND: Southwest 15 to 25 mph with gusts up to 40 mph. * HUMIDITY: 10 to 14 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ WYZ283-260200- /O.CON.KRIW.FW.W.0015.210825T1800Z-210826T0200Z/ Upper Wind River Basin/Wind River Basin- 345 AM MDT Wed Aug 25 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM NOON TODAY TO 8 PM MDT THIS EVENING... * IMPACTS: Low Humidities and Strong Gusty Winds will create erratic fire behavior and new fire starts. * AFFECTED AREA: In Central WY...Fire Weather Zone 283. * COUNTIES AFFECTED: In Central WY...Fremont. * WIND: Southwest 10 to 20 mph with gusts up to 35 mph. * HUMIDITY: 10 to 13 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ WYZ280-281-285-300-260200- /O.CON.KRIW.FW.W.0015.210825T1800Z-210826T0200Z/ Natrona County/Casper BLM-Johnson County/Casper BLM- South Bighorn Mountains-Casper Mountain- 345 AM MDT Wed Aug 25 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM NOON TODAY TO 8 PM MDT THIS EVENING... * IMPACTS: Low Humidities and Strong Gusty Winds will create erratic fire behavior and new fire starts. * AFFECTED AREA: In Central WY Fire Zones...280...285...300. In North Central WY Fire Zone....281. * COUNTIES AFFECTED: In Central WY...Fremont...Natrona. In North Central WY...Hot Springs...Johnson...Washakie. * WIND: Southwest 15 to 20 mph with gusts up to 35 mph. * HUMIDITY: 10 to 15 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ http://weather.gov/riverton
059 WWUS85 KRIW 251754 RFWRIW URGENT - FIRE WEATHER MESSAGE National Weather Service Riverton WY 1154 AM MDT Wed Aug 25 2021 WYZ277>279-289-260200- /O.CON.KRIW.FW.W.0015.210825T1800Z-210826T0200Z/ Lincoln and Uinta Counties/Lower Elevations- Upper Green River Basin/Rock Springs BLM- Sweetwater County/Rock Springs BLM/Flaming Gorge NRA- Granite/Green/Ferris/Rattlesnake Mountains- 1154 AM MDT Wed Aug 25 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT THIS EVENING... * IMPACTS: Low Humidities and Strong Gusty Winds will create erratic fire behavior with any new fire starts. * AFFECTED AREA: In Central WY Fire Zone....289. In Southwest WY Fire Zones...277...279. In West Central WY Fire Zone....278. * COUNTIES AFFECTED: In Central WY...Fremont...Natrona. In Southwest WY...Sweetwater...Uinta. In West Central WY...Lincoln...Sublette. * WIND: Southwest 15 to 25 mph with gusts up to 40 mph. * HUMIDITY: 10 to 14 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ WYZ283-260200- /O.CON.KRIW.FW.W.0015.210825T1800Z-210826T0200Z/ Upper Wind River Basin/Wind River Basin- 1154 AM MDT Wed Aug 25 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT THIS EVENING... * IMPACTS: Low Humidities and Strong Gusty Winds will create erratic fire behavior with any new fire starts. * AFFECTED AREA: In Central WY...Fire Weather Zone 283. * COUNTIES AFFECTED: In Central WY...Fremont. * WIND: Southwest 10 to 20 mph with gusts up to 35 mph. * HUMIDITY: 10 to 13 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ WYZ280-281-285-300-260200- /O.CON.KRIW.FW.W.0015.210825T1800Z-210826T0200Z/ Natrona County/Casper BLM-Johnson County/Casper BLM- South Bighorn Mountains-Casper Mountain- 1154 AM MDT Wed Aug 25 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT THIS EVENING... * IMPACTS: Low Humidities and Strong Gusty Winds will create erratic fire behavior with any new fire starts. * AFFECTED AREA: In Central WY Fire Zones...280...285...300. In North Central WY Fire Zone....281. * COUNTIES AFFECTED: In Central WY...Fremont...Natrona. In North Central WY...Hot Springs...Johnson...Washakie. * WIND: Southwest 15 to 20 mph with gusts up to 35 mph. * HUMIDITY: 10 to 15 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ Team Riverton/21
790 WWUS85 KRIW 260157 RFWRIW URGENT - FIRE WEATHER MESSAGE National Weather Service Riverton WY 757 PM MDT Wed Aug 25 2021 WYZ277>279-289-260300- /O.EXP.KRIW.FW.W.0015.000000T0000Z-210826T0200Z/ Lincoln and Uinta Counties/Lower Elevations- Upper Green River Basin/Rock Springs BLM- Sweetwater County/Rock Springs BLM/Flaming Gorge NRA- Granite/Green/Ferris/Rattlesnake Mountains- 757 PM MDT Wed Aug 25 2021 ...RED FLAG WARNING WILL EXPIRE AT 8 PM MDT THIS EVENING FOR FIRE WEATHER ZONES 277, 278, 279, AND 289... Winds have decreased this evening as relative humidities begin to recover; therefore, the Red Flag Warning will be allowed to expire. $$ WYZ283-260300- /O.EXP.KRIW.FW.W.0015.000000T0000Z-210826T0200Z/ Upper Wind River Basin/Wind River Basin- 757 PM MDT Wed Aug 25 2021 ...RED FLAG WARNING WILL EXPIRE AT 8 PM MDT THIS EVENING FOR FIRE WEATHER ZONE 283... Winds have decreased this evening as relative humidities begin to recover; therefore, the Red Flag Warning will be allowed to expire. $$ WYZ280-281-285-300-260300- /O.EXP.KRIW.FW.W.0015.000000T0000Z-210826T0200Z/ Natrona County/Casper BLM-Johnson County/Casper BLM- South Bighorn Mountains-Casper Mountain- 757 PM MDT Wed Aug 25 2021 ...RED FLAG WARNING WILL EXPIRE AT 8 PM MDT THIS EVENING FOR FIRE WEATHER ZONES 280, 281, 285, AND 300... Winds have decreased this evening as relative humidities begin to recover; therefore, the Red Flag Warning will be allowed to expire. $$
The office that day
Everything else NWS Riverton, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 24, 2:53 AM MDT | Fire Weather Watch | RIW | Fremont, Hot Springs, Johnson, Lincoln, Natrona, Sublette and 3 more | 10 hr |
Nearby
Red Flag Warnings in Wyoming, 2021Every red flag 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.