784
FNUS76 KOTX 171252
FWSOTX

Spot Forecast for Upper Smith...USFS
National Weather Service Spokane WA
552 AM PDT Thu Sep 17 2026

Forecast is based on forecast start time of 0600 PDT on September 17.
.DISCUSSION...

Conditions will be dry and seasonably warm over the burn site
Thursday and Friday with temperatures in the mid 60s to around mid
70s degrees and afternoon RHs falling into the upper 20s to mid
30s. Overnight RH recoveries Thursday night will be fair to good.
Winds will be light out of the Northeast on Thursday, then will
shift out of the southwest Thursday evening around 1900 hours.

If conditions become unrepresentative, contact the National Weather
Service.
***************************************************************
Forecasts for 20 foot wind speeds (valleys and ridge tops) are
10 minute averages reflecting RAWS wind.
***Ventilation Index is derived from transport wind
   multiplied by the mixing height divided by 100.
   Categories: low (< 200), moderate (200-500),
   high (500-800), and very high (> 800).
***************************************************************

.TODAY...

Sky/weather.........Sunny.
CWR.................0 percent.
Chance of lightning.0 percent.
Max temperature.....Mid Slopes to Ridgetops..........64-70.
                    Valley Bottom and Lower Slopes...70-76.
Min humidity........Mid Slopes to Ridgetops.........30-33 percent.
                    Valley Bottom to Lower Slopes...26-30 percent.
Wind (20 ft)........Valleys/Mid Slopes: Upslope/Upvalley winds
                    2 to 5 mph.
                    Ridgetops: North-Northeast winds 4 to 7 mph.
Mixing height.......Inversion lifts around 0700 hours. Mixing
                    height increasing to 3000 ft AGL by 1500 hours.
Transport winds.....North 5 to 6 mph.
Ventilation Index...Low (105).

.TONIGHT...

Sky/weather.........Partly cloudy.
CWR.................0 percent.
Chance of lightning.0 percent.
Min temperature.....42-47.
Max humidity........Mid Slopes to Ridgetops........57-66 percent
                    Valley Bottom to Lower Slopes...60-68 percent.
Wind (20 ft)........Valleys/Mid Slopes: Downslope/Downvalley
                    winds 1 to 4 mph.
                    Ridgetops: West winds up to 6 mph shifting to the
                    southwest 4 to 8 mph after 1900.
Mixing height.......Near surface AGL.
Transport winds.....Northwest around 5 mph.
Ventilation Index...Low (25).

.FRIDAY...

Sky/weather.........Sunny.
CWR.................0 percent.
Chance of lightning.0 percent.
Max temperature.....Mid Slopes to Ridgetops..........60-67.
                    Valley Bottom and Lower Slopes...70-77.
Min humidity........Mid Slopes to Ridgetops.........35-40 percent.
                    Valley Bottom to Lower Slopes...30-35 percent.
Wind (20 ft)........Valleys/Mid Slopes: Upslope/Upvalley winds 2 to
                    5 mph. Becoming east 3 to 6 mph after 1300.
                    Ridgetops: South-Southeast winds 4 to 7 mph.
Mixing height.......Inversion lifts around 0900 hours.2500 ft AGL
                    increasing to 4500 ft AGL in the afternoon.
Transport winds.....Light winds becoming southwest around 5 mph in
                    the afternoon.
Ventilation Index...Moderate (280).

$$
Forecaster...JCLEV
Requested by...Incident Commander
Type of request...WILDFIRE
.TAG 2621955.1/OTX
.DELDT 09/17/26
.FormatterVersion 2.0.0
.EMAIL jesse.countryman@usda.gov