FNUS76 KOTX 220037 FWSOTX Spot Forecast for HILL LOOP...WA DNR National Weather Service Spokane WA 537 PM PDT Fri Aug 21 2026 Forecast is based on forecast start time of 1900 PDT on August 21. ...HEAT ADVISORY IN EFFECT UNTIL 10 PM PDT THIS EVENING... ...RED FLAG WARNING IN EFFECT FROM 11 AM SATURDAY TO 8 AM PDT SUNDAY FOR LIGHTNING AND GUSTY OUTFLOW WINDS... .DISCUSSION... Mid and high clouds will be thickening after 1900. This activity has a 10% chance to produce sprinkles initially then 30% for light showers overnight into early Saturday morning. Any activity will be capable of brief erratic wind gusts of 15-20 mph. The threat for showers will move out by 0800 with a 30% chance for thunderstorms in the afternoon mainly between 1400-2200. Any storms will be capable of gusty outflow winds to 40 mph and brief rain with low probabilities for wetting rains. Winds overnight will be light with a general north to northeast direction. Winds will become southeast then south for Saturday with speeds increasing around 1500. A shift toward southwest winds is expected with the cold front passage 1900-2000 which will remain gusty for several hours before decreasing overnight. Breezy southerly winds return Sunday with cooler temperatures and higher humidity. 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). *************************************************************** .TONIGHT... Sky/weather.........Mostly cloudy. Spotty sprinkles 1900-2300 then 30% chance for high based showers 2300-0600. CWR.................0 percent. Chance of lightning.5 percent. Min temperature.....74. Max humidity........29-34 percent. Wind (20 ft)........North to northeast winds 2 to 5 mph. Brief erratic southerly winds near showers around 15 mph. Mixing height.......500 ft AGL. Transport winds.....North to northeast around 6 mph overnight. Ventilation Index...Low (24). .SATURDAY... Sky/weather.........Mostly sunny becoming partly cloudy with a 30 percent chance for showers and thunderstorms after 1400. CWR.................10 percent. Chance of lightning.30 percent. Max temperature.....93. Min humidity........19-24 percent. Wind (20 ft)........Northeast winds around 5 mph shifting to the southeast 5 to 8 mph in the morning then south 8 to 11 mph gusts 20 mph around 1500. Gusty and erratic winds expected near thunderstorms in the evening. Mixing height.......9000 ft AGL in the afternoon. Transport winds.....North around 8 mph shifting to the south 15 mph in the afternoon. Ventilation Index...Moderate (411) increasing to high (718) in the afternoon. .SATURDAY NIGHT... Sky/weather.........Mostly cloudy. Slight chance of showers and thunderstorms in the evening. CWR.................15 percent. Chance of lightning.25 percent. Min temperature.....58. Max humidity........66-71 percent. Wind (20 ft)........South winds 8 to 11 mph gusts to 20 mph shifting to the southwest 1900-2000. Winds decreasing southwest 4 to 8 mph gusts 12 mph after 2200. Gusty and erratic winds expected near thunderstorms in the evening. Mixing height.......6500 ft AGL falling to 500 ft AGL. Transport winds.....Southwest 13 mph decreasing southwest 7 mph. Ventilation Index...High (565) decreasing to low (28) overnight. .SUNDAY... Sky/weather.........Partly sunny. Slight chance of rain showers in the morning, then chance of rain showers and slight chance of thunderstorms in the afternoon. CWR.................15 percent. Chance of lightning.20 percent. Max temperature.....76. Min humidity........37-42 percent. Wind (20 ft)........South winds 5 to 10 mph gusts to 16 mph becoming southwest to west 5 to 9 mph late afternoon. Gusty and erratic winds expected near thunderstorms in the afternoon. Mixing height.......7000 ft AGL in the afternoon. Transport winds.....South around 9 mph shifting to the west around 10 mph in the afternoon. Ventilation Index...Moderate (439) increasing to high (643) in the afternoon. $$ Forecaster...SB Requested by...BROOKE SEITTERS Type of request...WILDFIRE .TAG 2620211.0/OTX .DELDT 08/21/26 .FormatterVersion 2.0.0 .EMAIL WANEC@FIRENET.GOV