FNUS76 KPDT 181602 FWSPDT Spot Forecast for SPRING CREEK FIRE...WALLA WALLA COUNTY FIRE DISTRICT 4 National Weather Service Pendleton OR 902 AM PDT Sat Jul 18 2026 Forecast is based on forecast start time of 0900 PDT on July 18. ***Thunderstorms imply gusty and erratic winds *** ***Winds are 20 foot 10-minute averages *** ***CWR: Chance of wetting rain 0.10 or greater *** ***Ventilation Index is derived from transport wind multiplied by the mixing height in 100's of ft. Categories are a generalized indicator only: low (< 200), moderate (200-500), high (500-700), and very high (> 700). *** If you have questions or concerns with this forecast, please contact our office at (541) 276-8134. .DISCUSSION...High pressure continues to strengthen over the fire area through the weekend, keeping skies clear and conditions drying. Inversion sets up between 2000-2100 and breaks between 0700-0800 Sunday. Diurnally and terrain driven winds persist, with directions primarily out of the west-southwest. .REST OF TODAY... Sky/weather.........Sunny (0-5 percent). Patchy smoke late in the afternoon. CWR.................0 percent. Chance of lightning.0 percent. Max temperature.....93-96. Min humidity........14-19 percent. Wind (20 ft)........West-southwest winds 8 to 12 mph with gusts up to 16 mph, peaking before 1300. Ridgetop wind.......West-southwest winds 10 to 15 mph with gusts up to 18 mph, peaking before 1300. Mixing height.......4500 ft AGL. Transport winds.....Southwest 10 to 13 mph. Ventilation Index...Low (130) increasing to moderate (370) in the afternoon. TIME (PDT) 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM 6PM 7PM 8PM Chc of ltng (%).0 0 0 0 0 0 0 0 0 0 0 0 Temp............71 75 79 83 84 88 91 91 91 92 88 83 RH..............38 37 32 28 26 23 21 20 18 17 19 25 20 FT wind dir..SW SW SW SW W W W W W W W SW 20 FT wind spd..11 11 11 10 10 10 10 10 10 10 10 8 20 FT wind gust.12 12 12 12 13 13 14 14 14 12 11 10 .TONIGHT... Sky/weather.........Clear (0-10 percent). Patchy smoke through the evening. CWR.................0 percent. Chance of lightning.0 percent. Min temperature.....Around 60. Max humidity........55-60 percent. Wind (20 ft)........Southwest winds 5 to 10 mph shifting to the south 4 to 8 mph after 2100. Ridgetop wind.......Southwest winds 6 to 12 mph shifting to the south 5 to 10 mph after 2100. Mixing height.......500 ft AGL. Transport winds.....Southwest 8 to 10 mph shifting to the south late in the evening. Ventilation Index...Low (150) decreasing to low (40) overnight. .SUNDAY... Sky/weather.........Sunny (20-30 percent). CWR.................0 percent. Chance of lightning.0 percent. Max temperature.....93-96. Min humidity........13-18 percent. Wind (20 ft)........South winds 3 to 7 mph shifting to the west 4 to 8 mph after 0900. Ridgetop wind.......South winds 4 to 8 mph shifting to the west 5 to 10 mph after 0900. Mixing height.......4300 ft AGL. Transport winds.....Southwest 7 to 8 mph shifting to the west 5 to 7 mph late in the morning. Ventilation Index...Low (70) increasing to moderate (210) in the afternoon. $$ Forecaster...Callihan Requested by...BRANDON MCKINNEY Type of request...WILDFIRE .TAG 2617669.0/PDT .DELDT 07/18/26 .FormatterVersion 2.0.0 .EMAIL jgolden@wwfire4.com,spotweather@wwfire4.com