990
FNUS75 KPIH 112317
FWSPIH

Spot Forecast for Big Rock Fire...BLM-IFD
National Weather Service Pocatello ID
517 PM MDT Tue Aug 11 2026

Forecast is based on forecast start time of 0600 MDT on August 12.
If conditions become unrepresentative, contact the National Weather
Service.

Please contact our office at (208) 232-9357, if you have questions
or concerns with this forecast.

.DISCUSSION...
The past week and a half of hot and dry weather has primed fuels for
significant pattern change that starts today (Wednesday) and is full
blown by Thursday. Remnants of a southwest monsoon will move into
southern Idaho, triggering scattered thunderstorms each afternoon
and evening. Temperatures will cool due to the clouds and
precipitation, and humidity will skyrocket upward. It is likely that
by Wednesday afternoon a Red Flag Warning will be issued for
scattered to numerous thunderstorms.

.WEDNESDAY...

Sky/weather.........Mostly cloudy, by 1600 becoming partly sunny. A
                     slight chance of dry thunderstorms after 1200.
CWR.................Zero.
Chance of thunder...23 percent.
Max temperature.....5100ft elevation...86.
Min humidity........5100ft elevation...24 percent.
Wind (20 ft)........Southeast 4 to 10 mph, by 1100 becoming southwest
                    8 to 15 mph gusts to 26 mph.
Mixing height.......Morning inversion around 6600ft elevation.
                    Mixing height rising to 9900ft to 11,000ft AGL.
Transport winds.....South southwest 18 mph, after inversion break
                    West 12 mph.
Rainfall amount.....None to trace.

.WEDNESDAY NIGHT...

Sky/weather.........Mostly clear, by 0300 becoming cloudy.
CWR.................Zero.
Chance of thunder...9 percent.
Min temperature.....5100ft elevation...59.
Max humidity........5100ft elevation...77 percent.
Wind (20 ft)........South 7 to 13 mph gusts to 22 mph, by 2200 becoming
                     southeast 4 to 10 mph gusts to 14 mph.
Mixing height.......Inversion developing around 6500ft elevation.
Transport winds.....West 12 mph, becoming south southeast 9 mph.
Rainfall amount.....None to trace.

.THURSDAY...

Sky/weather.........Cloudy, by 1700 becoming mostly cloudy. A 35 percent
                    chance of showers in the morning, by 1200 becoming
                    a 70 percent chance of showers. A chance of
                    thunderstorms. Gusts to 50 mph near thunderstorms.
CWR.................15 percent before 1200, 55 percent after.
Chance of thunder...10 percent before 1200, 37 percent after.
Max temperature.....5100ft elevation...74.
Min humidity........5100ft elevation...53 percent.
Wind (20 ft)........Southeast 3 to 9 mph gusts to 12 mph, by 1000
                     becoming southwest 4 to 10 mph gusts to 18 mph.
                     By 1200, wind becoming southwest 8 to 14 mph gusts
                     to 24 mph.
Mixing height.......Rising to 6600ft to 7700ft AGL.
Transport winds.....West southwest 15 mph.
Rainfall amount.....Extreme range trace to 0.60 of an inch.
                    Mostly likey amount 0.02 to 0.31 of an inch.

$$
Forecaster...Messick
Requested by...Dispatch
Type of request...WILDFIRE
.TAG 2618766.12/PIH
.DELDT 08/11/26
.FormatterVersion 2.0.0
.EMAIL ideic@firenet.gov,robert.ricks@mfd.id.gov,jmitchell@blm.gov,smaupin@blm.gov