474
FNUS75 KBYZ 042058
FWSBYZ
SPOT FORECAST FOR GRIFFIN...DOI
NATIONAL WEATHER SERVICE BILLINGS MT
258 PM MDT TUE AUG 4 2026
FORECAST IS BASED ON FORECAST START TIME OF 1600 MDT ON AUGUST 04.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.
PLEASE CONTACT OUR OFFICE IF YOU HAVE QUESTIONS
OR CONCERNS WITH THIS FORECAST.
DISCUSSION
THERE IS A NARROW WINDOW BETWEEN 8 PM MDT TO 1 AM MDT WHERE A
STRAY SHOWER OR STORM COULD ROLL OFF THE BIGHORN MOUNTAINS TOWARDS
THE INCIDENT SITE, HOWEVER THE CHANCE OF THIS IS QUITE LOW (15%).
WINDS TONIGHT WILL BE LIGHT VARIABLE, EVEN AT RIDGETOP, PRIMARILY
DRIVEN BY TERRAIN. WEDNESDAY WINDS WILL BE OUT OF THE NORTHWEST
REACHING 15 MPH AT RIDGETOP. HIGH TEMP WIL BE IN THE UPPER 80S
WITH MIN RH VALUES IN THE LOW TEENS. CONDITIONS WILL CONTINUE TO
SLOWLY GET HOTTER AND DRIER THROUGH FRIDAY WITH A POSSIBLE COLD
FRONT PASSAGE LATE THURSDAY INTO FRIDAY AM. WMR
REST OF TODAY
SKY/WEATHER.........MOSTLY SUNNY WITH HAZE.
CWR.................0 PERCENT.
CHANCE OF LIGHTNING.0 PERCENT.
MAX TEMPERATURE.....74-78.
MIN HUMIDITY........16-20 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......NORTHEAST WINDS 5 TO 10 MPH.
RIDGETOP...........NORTH AROUND 15 MPH.
MIXING HEIGHT.......7900 FT AGL.
TRANSPORT WINDS.....NORTHEAST AROUND 15 MPH.
TONIGHT
SKY/WEATHER.........PARTLY CLOUDY WITH HAZE. SLIGHT CHANCE OF A SHOWER
OR THUNDERSTORM IN THE EVENING. ERRATIC WIND GUSTS
EXPECTED NEAR THUNDERSTORMS.
CWR.................5 PERCENT.
CHANCE OF LIGHTNING.5 PERCENT.
MIN TEMPERATURE.....47-51.
MAX HUMIDITY........59-63 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......NORTHEAST WINDS 5 MPH BECOMING LIGHT AND TERRAIN DRIVEN
AFTER SUNSET.
RIDGETOP...........SOUTH-SOUTHWEST AROUND 10 MPH.
MIXING HEIGHT.......DECREASING TO 500 FT AGL OVERNIGHT.
TRANSPORT WINDS.....SOUTH AROUND 10 MPH.
WEDNESDAY
SKY/WEATHER.........MOSTLY SUNNY WITH HAZE.
CWR.................0 PERCENT.
CHANCE OF LIGHTNING.0 PERCENT.
MAX TEMPERATURE.....85-89.
MIN HUMIDITY........10-14 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......LIGHT WINDS BECOMING NORTHWEST 5 TO 10 MPH IN
THE AFTERNOON.
RIDGETOP...........NORTHWEST AROUND 15 MPH.
MIXING HEIGHT.......INCREASING TO 10900 FT AGL IN THE AFTERNOON.
TRANSPORT WINDS.....NORTHWEST AROUND 15 MPH.
FORECASTER...MATOS/MCKEOWN-ROBBIE
REQUESTED BY...JONATHAN MANTELLO
TYPE OF REQUEST...WILDFIRE
.TAG 2618924.1/BYZ
.DELDT 08/04/26
.FORMATTERVERSION 2.0.0
.EMAIL MTMCC@FIRENET.GOV
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