900
WWUS85 KRIW 080209
RFWRIW
URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE RIVERTON WY
809 PM MDT THU AUG 7 2025
WYZ285-287-080315-
/O.EXP.KRIW.FW.W.0009.000000T0000Z-250808T0200Z/
SOUTH BIGHORN MOUNTAINS-OWL CREEK MOUNTAINS-
809 PM MDT THU AUG 7 2025
..RED FLAG WARNING EXPIRED AT 8 PM MDT THURSDAY
RELATIVE HUMIDITY IS SLOWLY RISING ABOVE CRITICAL THRESHOLDS
THURSDAY EVENING. THEREFORE, THE RED FLAG WARNING HAS BEEN ALLOWED
TO EXPIRE. HOWEVER, GUSTY WEST WIND 15 TO 30 MPH PERSISTS FOR A
FEW MORE HOURS BEFORE SHIFTING TO THE NORTH BEFORE MIDNIGHT.
WYZ277>279-288-289-414-416-090200-
/O.CON.KRIW.FW.W.0009.000000T0000Z-250809T0200Z/
LINCOLN AND UINTA COUNTIES/LOWER ELEVATIONS-
UPPER GREEN RIVER BASIN/ROCK SPRINGS BLM-
SWEETWATER COUNTY/ROCK SPRINGS BLM/FLAMING GORGE NRA-
EAST WIND RIVER MOUNTAINS/SOUTH SHOSHONE NF-
GRANITE/GREEN/FERRIS/RATTLESNAKE MOUNTAINS-
SALT AND WYOMING RANGES/WEST ZONE BRIDGER TETON NF-
WEST WIND RIVER MOUNTAINS/EAST ZONE BRIDGER TETON NF-
809 PM MDT THU AUG 7 2025
..RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT FRIDAY
* AFFECTED AREA:
IN CENTRAL WY FIRE ZONES...288...289.
IN SOUTHWEST WY FIRE ZONES...277...279.
IN WEST CENTRAL WY FIRE ZONES...278...414...416.
* COUNTIES AFFECTED:
IN CENTRAL WY...FREMONT...NATRONA.
IN SOUTHWEST WY...SWEETWATER...UINTA.
IN WEST CENTRAL WY...LINCOLN...SUBLETTE.
* IMPACTS: THE COMBINATION OF LOW RELATIVE HUMIDITY AND GUSTY WIND
ASSOCIATED WITH PASSAGE OF A COLD FRONT COULD CAUSE ERRATIC FIRE
BEHAVIOR.
* COLD FRONT: A COLD FRONT WILL SWING WINDS TO THE WEST TO
NORTHWEST FRIDAY.
* WIND: FRIDAY WIND WILL BE FROM THE WEST TO NORTHWEST 15 TO 25
MPH WITH GUSTS 30 TO 40 MPH.
* 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.
WYZ280-283-090200-
/O.CON.KRIW.FW.W.0009.000000T0000Z-250809T0200Z/
NATRONA COUNTY/CASPER BLM-UPPER WIND RIVER BASIN/WIND RIVER BASIN-
809 PM MDT THU AUG 7 2025
..RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT FRIDAY
* AFFECTED AREA:
IN CENTRAL WY...FIRE WEATHER ZONES 280 AND 283.
* COUNTIES AFFECTED:
IN CENTRAL WY...FREMONT...NATRONA.
* IMPACTS: THE COMBINATION OF LOW RELATIVE HUMIDITY AND GUSTY WIND
ASSOCIATED WITH PASSAGE OF A COLD FRONT COULD CAUSE ERRATIC FIRE
BEHAVIOR.
* COLD FRONT: A COLD FRONT WILL SWING WINDS TO THE WEST TO
NORTHWEST FRIDAY.
* WIND: WEST TO NORTHWEST WIND 15 TO 25 MPH WITH GUSTS UP TO 35
MPH.
* 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.
WYZ300-090200-
/O.CON.KRIW.FW.W.0009.000000T0000Z-250809T0200Z/
CASPER MOUNTAIN-
809 PM MDT THU AUG 7 2025
..RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT FRIDAY
* AFFECTED AREA:
IN CENTRAL WY...FIRE WEATHER ZONE 300.
* COUNTIES AFFECTED:
IN CENTRAL WY...NATRONA.
* IMPACTS: THE COMBINATION OF LOW RELATIVE HUMIDITY AND GUSTY WIND
ASSOCIATED WITH PASSAGE OF A COLD FRONT COULD CAUSE ERRATIC FIRE
BEHAVIOR.
* COLD FRONT: A COLD FRONT WILL SWING WINDS TO THE WEST TO
NORTHWEST FRIDAY.
* WIND: WESTERLY WIND 15 TO 25 MPH WITH GUSTS UP TO 35 MPH.
* HUMIDITY: AS LOW AS 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.
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