FNUS76 KOTX 221953 FWSOTX Spot Forecast for Upper Smith South...Upper Smith National Weather Service Spokane WA 1253 PM PDT Sat Aug 22 2026 Forecast is based on forecast start time of 0600 PDT on August 23. ...RED FLAG WARNING IN EFFECT FROM 4 PM THIS AFTERNOON TO 11 AM PDT SUNDAY FOR LIGHTNING AND GUSTY OUTFLOW WINDS... .DISCUSSION... 209: Saturday started off very warm and dry. Elevated showers passed over the fire in the afternoon delivering gusty, erratic winds near 25 mph. Temperatures quickly warmed into the 80s by midday then heating was disrupted by the cloud cover and showers in the afternoon. Humidity trends were similar bottoming out between 20-25% before climbing toward 25-30% in the afternoon. There is a moderate threat for showers and thunderstorms over the fire Saturday evening into Sunday. Storms will be capable of gusty outflow winds in excess of 30 mph along with brief downpours of rain and small hail. Breezy southwest winds will be in place Sunday with gusts up to 20 mph. Temperatures will cool into the 60s and 70s. Warmer and drier conditions return Monday and Tuesday with light, terrain driven winds. Spot Discussion: A robust upper low moving through the region will keep a moderate risk for showers and thunderstorms on Sunday. General winds from the southwest will stand a good chance to overpower terrain driven flow and dominate the landscape. Some sheltering or eddying is possible on east aspects facing the Kootenai River. The threat for thunderstorms will be from 1200-1700. A few storms could be strong with heavy downpours of rain/small hail and wind gusts around 30 mph. Conditions dry out Sunday evening with a subtle warming and drying trend Monday. 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). *************************************************************** .SUNDAY... Sky/weather.........Partly sunny. 30% chance of rain showers in the morning then 40% chance of showers and thunderstorms in the afternoon. CWR.................15 percent. Chance of lightning.20 percent. Max temperature.....69-75. Min humidity........40-45 percent. Wind (20 ft)........Southwest winds 6 to 10 mph with gusts to around 18 mph. Gusty and erratic winds expected near thunderstorms in the afternoon. Mixing height.......5400 ft AGL in the afternoon. Transport winds.....Southwest 16 to 19 mph. Ventilation Index...High (578) increasing to very high (870) in the afternoon. .SUNDAY NIGHT... Sky/weather.........Partly cloudy. CWR.................0 percent. Chance of lightning.5 percent. Min temperature.....45-50. Max humidity........90-95 percent. Wind (20 ft)........West winds 5 to 9 mph with gusts to around 16 mph in the evening becoming west to northwest 2 to 5 mph overnight. Mixing height.......5000 ft AGL falling to 500 ft AGL. Transport winds.....West 7 to 11 mph. Ventilation Index...High (695) decreasing to low (34) overnight. .MONDAY... Sky/weather.........Mostly Sunny. CWR.................0 percent. Chance of lightning.0 percent. Max temperature.....77-83. Min humidity........36-41 percent. Wind (20 ft)........Variable winds 1 to 3 mph in the morning becoming upslope/upvalley 3 to 8 mph. Mixing height.......6000 ft AGL in the afternoon. Transport winds.....Variable to west 5 mph. Ventilation Index...Low (189) increasing to moderate (359) in the afternoon. $$ Forecaster...SB Requested by...Noelle Type of request...WILDFIRE .TAG 2620106.2/OTX .DELDT 08/22/26 .FormatterVersion 2.0.0 .EMAIL 2026.uppersmith.plans@firenet.gov,david_pearson@firenet.gov,idcdc@firenet.gov