366
FNUS76 KOTX 061854
FWSOTX

Spot Forecast for Upper Smith South...Upper Smith
National Weather Service Spokane WA
1154 AM PDT Sun Sep 6 2026

Forecast is based on forecast start time of 0600 PDT on September 07.

.DISCUSSION...

209: Showery weather on Sunday with highs ranging from 53 (top
elevation of fire area) to 72 (bottom elevation of fire area).
Relative humidity recoveries Friday morning were excellent. Minimum
relative humidities ranged from 45 to 55 percent.

During the day Monday rain showers will occur through the day along
with a chance of thunderstorms.

Spot Discussion: On Monday rain showers will be on the increase
as a low pressure system tracks through the area. Forecast rain
amounts for the fire area are 0.50-1.00 inches. Here is the
probability of various rain amounts occurring through 11 PM Monday:
.10 inches or more 95 percent, .25 inches or more 85 percent,
.50 inches or more 70 percent, 1.00 inch or more 35 percent,
1.50 inches or more 5 percent. Tuesday will be warmer and drier,
although a chance of rain showers will linger especially in the
morning.

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

.LABOR DAY...

Sky/weather.........Cloudy. Rain showers and a 25 percent
                    chance of thunderstorms through the day. Patchy fog.
CWR.................80 percent.
Chance of lightning.25 percent.
Max temperature.....Mid Slopes to Ridgetops...44-53.
                    Valley Bottom and Lower Slopes...54-61.
Min humidity........75-90 percent.
Wind (20 ft)........Light winds except southwest 5 to 10 mph with gusts
                    up to 20 mph on ridgetops and upper slopes in the
                    afternoon. Gusty and erratic winds possible near
                    thunderstorms.
Mixing height.......Near surface in the morning increasing to 1000
                    ft AGL in the afternoon.
Transport winds.....West 5 to 15 mph.
Ventilation Index...Low (127).

.MONDAY NIGHT...

Sky/weather.........Cloudy. Rain. Patchy fog.
CWR.................70 percent.
Chance of lightning.10 percent.
Min temperature.....40-50.
Max humidity........95-100 percent.
Wind (20 ft)........Light winds, except southwest 6 to 12 mph on
                    ridgetops and upper slopes.
Mixing height.......Near surface.
Transport winds.....Southwest 5 to 15 mph.
Ventilation Index...Low (67).

.TUESDAY...

Sky/weather.........Mostly cloudy. Chance of rain showers in the
                    morning, then slight chance of rain showers in
                    the afternoon.
CWR.................15 percent.
Chance of lightning.5 percent.
Max temperature.....Mid Slopes to Ridgetops...51-61.
                    Valley Bottom and Lower Slopes...62-70.
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.......Near surface through 1000 increasing to 3000 ft AGL
                    in the afternoon.
Transport winds.....Southwest 5 to 10 mph.
Ventilation Index...Moderate (218).

$$
Forecaster...JW
Requested by...Wendy
Type of request...WILDFIRE
.TAG 2620106.17/OTX
.DELDT 09/06/26
.FormatterVersion 2.0.0
.EMAIL idcdc@firenet.gov,2026.uppersmith.plans@firenet.gov