FNUS76 KOTX 210910

FWSOTX



Spot Forecast for Upper Smith...USFS

National Weather Service Spokane WA

210 AM PDT Mon Sep 21 2026



Forecast is based on forecast start time of 0600 PDT on September 21. 

.DISCUSSION...



Dry, mild conditions, with winds increasing slightly this afternoon 

into Tuesday. Clouds increase tonight into Tuesday, with temperatures 

start to cool. Continued cooling for middle to late week, with 

increasing rain and high mountain snow chances Thursday night and 

Friday, with chances continuing into Saturday. Highest potential 

for wetting rain is Friday at around 40-50 percent. Locally breezy 

each afternoon, especially Friday with gusts near 20 mph possible.



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.........Mostly sunny. 

CWR.................0 percent. 

Chance of lightning.0 percent. 

Max temperature.....Ridgetops: 57-62

                    Valley: 63-71. 

Min humidity........Ridgetops: 40-45 percent

                    Valleys: 33-39 percent. 

Wind (20 ft)........Downslope/downvalley 3 to 6 mph, becoming 

                    southwest 5 to 10 mph in late afternoon.

                    Gusts to 15 mph on the ridgetops. 

Mixing height.......5000 ft AGL in the afternoon. 

Transport winds.....Southwest 5 to 10 mph. 

Ventilation Index...Low (177) increasing to moderate (478) in the 

                    afternoon. 



.TONIGHT...



Sky/weather.........Partly cloudy then becoming mostly cloudy. 

CWR.................0 percent. 

Chance of lightning.0 percent. 

Min temperature.....46-51. 

Max humidity........66-74 percent. 

Wind (20 ft)........Southwest winds 5 to 10 mph with gusts

                    to 15 mph on the ridgetops.

Mixing height.......1500 ft AGL. 

Transport winds.....Southwest around 7 mph. 

Ventilation Index...Low (108). 



.TUESDAY...



Sky/weather.........Mostly cloudy. 

CWR.................0 percent. 

Chance of lightning.0 percent. 

Max temperature.....Ridgetops: 54-60

                    Valleys:61-67. 

Min humidity........Ridgetops: 46-52 percent.

                    Valleys: 38-45 percent. 

Wind (20 ft)........South winds up to 5 to 10 mph, 

                    with gusts to 17 mph.

Mixing height.......5500 ft AGL in the afternoon. 

Transport winds.....Southwest 7 to 12 mph. 

Ventilation Index...Moderate (399) increasing to high (672) in the 

                    afternoon. 



$$

Forecaster...MSC

Requested by...Incident Commander

Type of request...WILDFIRE

.TAG 2621955.5/OTX

.DELDT 09/21/26

.FormatterVersion 2.0.0

.EMAIL jesse.countryman@usda.gov