FNUS76 KPDT 181359 FWSPDT Spot Forecast for Three Trough Springs...USFS National Weather Service Pendleton OR 659 AM PDT Sat Jul 18 2026 Forecast is based on forecast start time of 0600 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... Elevated fire weather conditions persist with low RHs and breezy winds. High pressure strengthens over the fire area through the weekend, keeping skies mostly clear as a warming and drying trend continues. Winds will be light and variable Saturday morning becoming north-northwest and picking up through the afternoon and evening. Winds remain breezy out of the north Saturday night, then let up early Sunday morning before picking up out of the north again Sunday afternoon. RH recovery Saturday night will be poor. .TODAY... Sky/weather.........Sunny (0-10 percent). Patchy smoke. CWR.................0 percent. Chance of lightning.0 percent. Max temperature.....82-86. Min humidity........17-21 percent. Wind (20 ft)........Light and variable winds 1 to 3 mph becoming north-northwest 5 to 9 mph after 1300, then increasing to 10 to 14 mph after 1500. Mixing height.......Inversion lifting around 0900. Mixing height increasing to 6500 ft AGL in the afternoon. Transport winds.....West 8 to 11 mph increasing to 15 to 21 mph after 1200. Ventilation Index...Low (40) increasing to moderate (400) in the afternoon. TIME (PDT) 6 AM 8 AM 10 AM NOON 2 PM 4 PM Chc of ltng (%).0 0 0 0 0 0 Temp............56 63 72 80 83 84 RH..............63 47 29 24 21 20 20 ft wind......NW 3 SE 2 SW 2 W 4 N 9 N 12 20 ft wind gust.5 5 6 8 12 14 .TONIGHT... Sky/weather.........Clear (0-15 percent). Patchy smoke in the evening and overnight. CWR.................0 percent. Chance of lightning.0 percent. Min temperature.....53-56. Max humidity........52-56 percent. Wind (20 ft)........North winds 10 to 14 mph with gusts to around 20 mph in the evening decreasing to 6 to 9 mph after 2200. Mixing height.......Falling to 500 ft AGL around 2100. Transport winds.....Northwest 13 to 20 mph in the early evening becoming north 11 to 16 mph after 1900. Ventilation Index...Moderate (250) decreasing to low (30) overnight. .SUNDAY... Sky/weather.........Sunny (0-20 percent) in the morning then becoming partly sunny (20-40 percent) in the afternoon. CWR.................0 percent. Chance of lightning.0 percent. Max temperature.....84-87. Min humidity........13-17 percent. Wind (20 ft)........Light and variable winds 1 to 4 mph in the morning becoming north 7 to 12 mph after 1200. Mixing height.......Inversion lifting around 0900. Mixing heights increasing to 6500 ft AGL in the afternoon. Transport winds.....North around 5 mph shifting to the west 7 to 13 mph in the afternoon. Ventilation Index...Low (30) increasing to high (510) in the afternoon.$$ Forecaster...NWS Spokane Requested by...Kristen Marshall Type of request...WILDFIRE .TAG 2617657.0/PDT .DELDT 07/18/26 .FormatterVersion 2.0.0 .EMAIL kristen.marshall@usda.gov