Alert archive / Wyoming / Red Flag Warnings in 2021
Red Flag Warning 5, NWS Riverton, WY
NWS Riverton, WY issued this red flag warning at Jul 12, 2021, 2:06 PM MDT for 9 counties in Wyoming. It took effect at Jul 13, 2021, 1:00 PM MDT. It was in force for 10 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
- Jul 12, 2021, 2:06 PM MDT (20:06 UTC)
- In effect from
- Jul 13, 2021, 1:00 PM MDT
- Expired
- Jul 13, 2021, 11:00 PM MDT
- In force
- 10 hr
- Issued by
- NWS Riverton, WY
Counties Big Horn County, WY, Fremont County, WY, Hot Springs County, WY, Johnson County, WY, Lincoln County, WY, Park County, WY, Sublette County, WY, Sweetwater County, WY, Uinta County, WY
The radar
The Riverton/Lander radar (KRIW), 45 km from the middle of the area, began a volume at 20:07 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, 8.1 hours before the alert went out and 51 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
- 3063 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- -35 m²/s²
- 0-3 km storm-relative helicity
- 138 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
601 WWUS85 KRIW 122006 RFWRIW URGENT - FIRE WEATHER MESSAGE National Weather Service Riverton WY 206 PM MDT Mon Jul 12 2021 WYZ277>279-131200- /O.UPG.KRIW.FW.A.0003.210713T1900Z-210714T0300Z/ /O.NEW.KRIW.FW.W.0005.210713T1900Z-210714T0300Z/ Lincoln and Uinta Counties/Lower Elevations- Upper Green River Basin/Rock Springs BLM- Sweetwater County/Rock Springs BLM/Flaming Gorge NRA- 206 PM MDT Mon Jul 12 2021 ...RED FLAG WARNING IN EFFECT FROM 1 PM TO 9 PM MDT TUESDAY... The National Weather Service in Riverton has issued a Red Flag Warning, which is in effect from 1 PM to 9 PM MDT Tuesday. * IMPACTS: Low Humidities...Strong Gusty Winds...and Dry Thunderstorms with gusty and erratic outflow winds will create erratic fire behavior and new fire starts. * AFFECTED AREA: In Southwest WY Fire Zones...277...279. In West Central WY Fire Zone....278. * COUNTIES AFFECTED: In Southwest WY...Sweetwater...Uinta. In West Central WY...Lincoln...Sublette. * WIND: West 10 to 20 mph with gusts up to 35 mph. * HUMIDITY: As low as 10 percent. * THUNDERSTORMS: 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. && $$ WYZ275-276-286-131200- /O.UPG.KRIW.FW.A.0003.210713T1900Z-210714T0300Z/ /O.NEW.KRIW.FW.W.0005.210713T1900Z-210714T0300Z/ North Big Horn Basin/Worland BLM-Cody Foothills- Absaroka Mountains/North Shoshone NF- 206 PM MDT Mon Jul 12 2021 ...RED FLAG WARNING IN EFFECT FROM 1 PM TO 9 PM MDT TUESDAY... The National Weather Service in Riverton has issued a Red Flag Warning, which is in effect from 1 PM to 9 PM MDT Tuesday. the Fire Weather Watch is no longer in effect. * IMPACTS: Dry Thunderstorms with gusty and erratic outflow winds will create erratic fire behavior and new fire starts. * AFFECTED AREA: In North Central WY Fire Zones...275...276. In Northwest WY Fire Zone....286. * COUNTIES AFFECTED: In Central WY...Fremont. In North Central WY...Big Horn...Hot Springs...Park. * WIND: Northwest 10 to 20 mph with gusts up to 30 mph. * THUNDERSTORMS: There will be an increased chance for lightning activity with thunderstorms. * HUMIDITY: As low as 20 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ WYZ281-131200- /O.UPG.KRIW.FW.A.0003.210713T1900Z-210714T0500Z/ /O.NEW.KRIW.FW.W.0005.210713T1900Z-210714T0500Z/ Johnson County/Casper BLM- 206 PM MDT Mon Jul 12 2021 ...RED FLAG WARNING IN EFFECT FROM 1 PM TO 11 PM MDT TUESDAY... The National Weather Service in Riverton has issued a Red Flag Warning, which is in effect from 1 PM to 11 PM MDT Tuesday. the Fire Weather Watch is no longer in effect. * IMPACTS: Dry Thunderstorms with gusty and erratic outflow winds will create erratic fire behavior and new fire starts. * AFFECTED AREA: In North Central WY...Fire Weather Zone 281. * COUNTIES AFFECTED: In North Central WY...Johnson. * WIND: East 10 to 20 mph with gusts up to 30 mph. * THUNDERSTORMS: There will be an increased chance for lightning activity with thunderstorms. * HUMIDITY: As low as 25 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. && $$ WYZ414-131200- /O.NEW.KRIW.FW.W.0005.210713T1900Z-210714T0300Z/ Salt and Wyoming Ranges/West Zone Bridger Teton NF- 206 PM MDT Mon Jul 12 2021 ...RED FLAG WARNING IN EFFECT FROM 1 PM TO 9 PM MDT TUESDAY... The National Weather Service in Riverton has issued a Red Flag Warning, which is in effect from 1 PM to 9 PM MDT Tuesday. * IMPACTS: Low Humidities...Strong Gusty Winds...and Dry Thunderstorms with gusty and erratic outflow winds will create erratic fire behavior and new fire starts. * AFFECTED AREA: In West Central WY...Fire Weather Zone 414. * COUNTIES AFFECTED: In West Central WY...Lincoln...Sublette. * WIND: West 10 to 20 mph with gusts up to 35 mph. * THUNDERSTORMS: * HUMIDITY: As low as 15 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ http://weather.gov/riverton
3 follow-up statements
897 WWUS85 KRIW 130851 RFWRIW URGENT - FIRE WEATHER MESSAGE National Weather Service Riverton WY 251 AM MDT Tue Jul 13 2021 WYZ277>279-414-140000- /O.CON.KRIW.FW.W.0005.210713T1900Z-210714T0300Z/ Lincoln and Uinta Counties/Lower Elevations- Upper Green River Basin/Rock Springs BLM- Sweetwater County/Rock Springs BLM/Flaming Gorge NRA- Salt and Wyoming Ranges/West Zone Bridger Teton NF- 251 AM MDT Tue Jul 13 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM 1 PM THIS AFTERNOON TO 9 PM MDT THIS EVENING... * IMPACTS: Low Humidities...Strong Gusty Winds...and Dry Thunderstorms with gusty and erratic outflow winds will create erratic fire behavior and new fire starts. * AFFECTED AREA: In Southwest WY Fire Zones...277...279. In West Central WY Fire Zones...278...414. * COUNTIES AFFECTED: In Southwest WY...Sweetwater...Uinta. In West Central WY...Lincoln...Sublette. * WIND: West 10 to 20 mph with gusts up to 35 mph. * THUNDERSTORMS: There will be an increased chance for lightning activity with thunderstorms. * HUMIDITY: As low as 10 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. && $$ WYZ275-276-286-140000- /O.CON.KRIW.FW.W.0005.210713T1900Z-210714T0300Z/ North Big Horn Basin/Worland BLM-Cody Foothills- Absaroka Mountains/North Shoshone NF- 251 AM MDT Tue Jul 13 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM 1 PM THIS AFTERNOON TO 9 PM MDT THIS EVENING... * IMPACTS: Low Humidities...Strong Gusty Winds...and Thunderstorms with gusty and erratic outflow winds will create erratic fire behavior and new fire starts. * AFFECTED AREA: In North Central WY Fire Zones...275...276. In Northwest WY Fire Zone....286. * COUNTIES AFFECTED: In Central WY...Fremont. In North Central WY...Big Horn...Hot Springs...Park. * WIND: Northwest 10 to 20 mph with gusts up to 30 mph. * THUNDERSTORMS: There will be an increased chance for lightning activity with thunderstorms. * HUMIDITY: As low as 20 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ WYZ281-140000- /O.CON.KRIW.FW.W.0005.210713T1900Z-210714T0500Z/ Johnson County/Casper BLM- 251 AM MDT Tue Jul 13 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM 1 PM THIS AFTERNOON TO 11 PM MDT THIS EVENING... * IMPACTS: Low Humidities...Strong Gusty Winds...and Thunderstorms with gusty and erratic outflow winds will create erratic fire behavior and new fire starts. * AFFECTED AREA: In North Central WY...Fire Weather Zone 281. * COUNTIES AFFECTED: In North Central WY...Johnson. * WIND: East 10 to 20 mph with gusts up to 30 mph. * THUNDERSTORMS: There will be an increased chance for lightning activity with thunderstorms. * HUMIDITY: As low as 25 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. && $$ http://weather.gov/riverton
739 WWUS85 KRIW 140249 RFWRIW URGENT - FIRE WEATHER MESSAGE National Weather Service Riverton WY 849 PM MDT Tue Jul 13 2021 WYZ277>279-414-140400- /O.EXP.KRIW.FW.W.0005.000000T0000Z-210714T0300Z/ Lincoln and Uinta Counties/Lower Elevations- Upper Green River Basin/Rock Springs BLM- Sweetwater County/Rock Springs BLM/Flaming Gorge NRA- Salt and Wyoming Ranges/West Zone Bridger Teton NF- 849 PM MDT Tue Jul 13 2021 ...RED FLAG WARNING WILL EXPIRE AT 9 PM MDT THIS EVENING... Humidity has increased and wind has decreased along with cooling temperatures. Thus, Red Flag conditions will not occur after 9 PM this evening. Therefore, the Red Flag Warning will expire at 9 PM. $$ WYZ275-276-286-140400- /O.EXP.KRIW.FW.W.0005.000000T0000Z-210714T0300Z/ North Big Horn Basin/Worland BLM-Cody Foothills- Absaroka Mountains/North Shoshone NF- 849 PM MDT Tue Jul 13 2021 ...RED FLAG WARNING WILL EXPIRE AT 9 PM MDT THIS EVENING... Thunderstorm activity will be quite isolated after 9 PM. Humidity has increased and wind speeds will be decreasing through late evening. Thus, Red Flag conditions will not occur after 9 PM. Therefore, the Red Flag Warning will expire at 9 PM. $$ WYZ281-140500- /O.CON.KRIW.FW.W.0005.000000T0000Z-210714T0500Z/ Johnson County/Casper BLM- 849 PM MDT Tue Jul 13 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 PM MDT THIS EVENING... * IMPACTS: Strong Gusty Winds and Thunderstorms with gusty and erratic outflow winds will create erratic fire behavior if there are any new fire starts. * AFFECTED AREA: In North Central WY...Fire Weather Zone 281. * COUNTIES AFFECTED: In North Central WY...Johnson. * WIND: North 15 to 20 mph with gusts up to 25 mph. * THUNDERSTORMS: There will be an increased chance for lightning activity with thunderstorms. * HUMIDITY: As low as 26 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ http://weather.gov/riverton
636 WWUS85 KRIW 140445 RFWRIW URGENT - FIRE WEATHER MESSAGE National Weather Service Riverton WY 1045 PM MDT Tue Jul 13 2021 WYZ281-140545- /O.EXP.KRIW.FW.W.0005.000000T0000Z-210714T0500Z/ Johnson County/Casper BLM- 1045 PM MDT Tue Jul 13 2021 ...RED FLAG WARNING WILL EXPIRE AT 11 PM MDT THIS EVENING... Red Flag conditions are not expected after 11 PM, thus the Reg FLag Warning will be expiring at 11 PM. $$ http://weather.gov/riverton
The office that day
Everything else NWS Riverton, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 11, 7:25 PM MDT | Special Weather Statement | RIW | 35 min | |
| Jul 11, 8:01 PM MDT | Special Weather Statement | RIW | Big Horn | 29 min |
| Jul 11, 8:32 PM MDT | Special Weather Statement | RIW | Big Horn | 28 min |
| Jul 11, 8:59 PM MDT | Special Weather Statement | RIW | Washakie | 31 min |
| Jul 12, 3:35 AM MDT | Fire Weather Watch | RIW | Big Horn, Fremont, Hot Springs, Johnson, Lincoln, Park and 3 more | 11 hr |
| Jul 12, 4:59 PM MDT | Special Weather Statement | RIW | Sublette | 46 min |
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.