100
FNUS76 KOTX 071256
FWSOTX

Spot Forecast for Upper Smith...Upper Smith
National Weather Service Spokane WA
556 AM PDT Mon Sep 7 2026

Forecast is based on forecast start time of 0600 PDT on September 08.
.DISCUSSION...

Shower chances decrease through the morning on Tuesday. Weather
trends warmer and drier Tuesday afternoon through Thursday. Winds
will be terrain driven during the overnight periods for all
terrain and then for the lower slopes and valleys in the
afternoons. Winds become breezier on Thursday out of the west with
gusts up to 17 mph across the ridgetops. Relative humidity
recoveries will be good Tuesday night and fair Wednesday night.
Weather trends cooler and wetter Thursday night into the weekend.

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).
***************************************************************

.TUESDAY...

Sky/weather.........Cloudy then becoming mostly sunny. 50% chance of
                    rain showers in the morning decreasing to a 15%
                    chance in the afternoon.
CWR.................10 percent.
Chance of lightning.10 percent.
Max temperature.....Mid Slopes to Ridgetops...51-58.
                    Valley Bottom and Lower Slopes...62-66.
Min humidity........Mid Slopes to Ridgetops...58-65 percent.
                    Valley Bottom and Lower Slopes: 48-58 percent.
Wind (20 ft)........Southwest 5 to 10 mph on ridgetops. Slope and valley
                    winds light in the morning then upslope/upvalley 2 to 5
                    mph in the afternoon.
Mixing height.......3500 ft AGL in the afternoon.
Transport winds.....West 5 to 9 mph.
Ventilation Index...Low (140) increasing to moderate (328) in the
                    afternoon.

.TUESDAY NIGHT...

Sky/weather.........Partly cloudy.
CWR.................0 percent.
Chance of lightning.0 percent.
Min temperature.....42-50.
Max humidity........77-85 percent.
Wind (20 ft)........Downslope/downvalley 1 to 4 mph.
Mixing height.......Near the surface.
Transport winds.....Southwest 7 to 9 mph.
Ventilation Index...Low (96).

.WEDNESDAY...

Sky/weather.........Mostly sunny.
CWR.................0 percent.
Chance of lightning.0 percent.
Max temperature.....Mid Slopes to Ridgetops...60-65.
                    Valley Bottom and Lower Slopes...68-72.
Min humidity........Mid Slopes to Ridgetops...38-48 percent.
                    Valley Bottom and Lower Slopes: 30-40 percent.
Wind (20 ft)........Southwest 4 to 8 mph on ridgetops. Slope and valley
                    winds light in the morning then upslope/upvalley 2 to 5
                    mph in the afternoon.
Mixing height.......5000 ft AGL in the afternoon.
Transport winds.....West 8 to 14 mph.
Ventilation Index...Moderate (298) increasing to high (637) in the
                    afternoon.

.WEDNESDAY NIGHT...

Sky/weather.........Partly cloudy.
CWR.................0 percent.
Chance of lightning.0 percent.
Min temperature.....45-50.
Max humidity........64-70 percent.
Wind (20 ft)........Downslope/downvalley 2 to 5 mph.
Mixing height.......Near the surface.
Transport winds.....Southwest 7 to 9 mph.
Ventilation Index...Low (96).

.THURSDAY...

Sky/weather.........Mostly sunny.
CWR.................0 percent.
Chance of lightning.0 percent.
Max temperature.....Mid Slopes to Ridgetops...59-64.
                    Valley Bottom and Lower Slopes...66-71.
Min humidity........Mid Slopes to Ridgetops...36-46 percent.
                    Valley Bottom and Lower Slopes: 28-38 percent.
Wind (20 ft)........Light winds in the morning becoming west 6 to 9 mph
                    in the afternoon. Wind gusts 13 to 17 mph in the
                    afternoon.
Mixing height.......6500 ft AGL in the afternoon.
Transport winds.....West 10 to 16 mph.
Ventilation Index...Moderate (298) increasing to very high (1068) in the
                    afternoon.

$$
Forecaster...VT
Requested by...Wendy
Type of request...WILDFIRE
.TAG 2621350.0/OTX
.DELDT 09/07/26
.FormatterVersion 2.0.0
.EMAIL idcdc@firenet.gov,2026.uppersmith.plans@firenet.gov