FNUS75 KTFX 181317 FWSTFX Spot Forecast for Valentine...Wildland Fire Service National Weather Service Great Falls MT 717 AM MDT Sat Jul 18 2026 Forecast is based on forecast start time of 0700 MDT on July 18. If conditions become unrepresentative...contact the National Weather Service. .DISCUSSION... Another round of showers and thunderstorms is possible across the incident area from the late afternoon through evening hours tonight, but shower and thunderstorm coverage will isolated in nature. Primary hazard with any precipitation will be gusty and erratic outflow winds. High temperatures through the weekend will be hot and in the mid-90s, with low afternoon relative humidity and only moderate recovery during the overnight hours. Overall dry conditions are expected on Sunday, but an isolated shower or storm over the Snowy and Little Rockies could produce outflow winds that would lead to erratic wind directions across the incident area during the afternoon hours. .REST OF TODAY... Sky/weather.........Partly sunny (50-60 percent) then becoming sunny (15-25 percent). Slight chance of showers early in the morning. Slight chance of showers and thunderstorms late in the afternoon. CWR.................5 percent. Chance of thunder...18 percent. Max temperature.....91-96. Min humidity........24-29 percent. Wind (20 ft)........ Slope/valley.......South winds around 5 mph shifting to the northwest late in the afternoon. Gusty and erratic winds expected near thunderstorms late in the afternoon. Ridgetop...........South around 10 mph shifting to the west late in the morning. Mixing height.......7500 ft AGL. Transport winds.....South 5 to 10 mph shifting to the northwest late in the afternoon. TIME (MDT) 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........62 47 17 14 9 5 20 27 29 32 38 Weather cov.....SCH SCH SCH Weather type....RW RW RW Tstm cov........ SCH CWR.............10 10 10 10 10 10 10 10 10 10 10 Chc of thdr (%).0 0 0 0 0 0 0 10 0 10 20 Temp............70 72 75 80 83 85 88 91 91 92 93 RH..............67 63 58 52 49 46 41 38 36 33 30 20 FT wind dir..SE S S S S S SW W W NW NW 20 FT wind spd..5 5 5 5 5 5 5 5 5 5 5 20 FT wind gust.10 10 10 10 10 10 10 15 15 15 15 Ridge wind dir..S S S S SW W W W W W W Ridge wind spd..10 10 10 10 5 5 5 10 10 10 10 Mix hgt (kft)...0.5 1.0 1.5 2.0 3.0 4.5 5.5 6.5 7.0 7.5 7.5 Transp wind dir.S S S S S S S SW W NW NW Transp wind spd.5 10 10 10 10 5 5 5 5 5 10 .TONIGHT... Sky/weather.........Partly cloudy (40-50 percent) then becoming mostly cloudy (50-60 percent). Slight chance of showers and thunderstorms in the evening, then chance of showers and thunderstorms overnight. CWR.................5 percent increasing to 20 percent overnight. Chance of thunder...25 percent. Min temperature.....67-72. Max humidity........51-56 percent. Wind (20 ft)........ Slope/valley.......North winds around 5 mph shifting to the southeast late in the evening, then shifting to the southwest overnight. Gusty and erratic winds expected near thunderstorms. Ridgetop...........West 10 to 15 mph shifting to the southwest 15 to 20 mph in the late evening and overnight. Mixing height.......500 ft AGL. Transport winds.....Variable winds around 10 mph through the evening shifting to the northwest after 3 am. TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM Sky (%).........43 43 43 43 43 43 55 55 55 55 55 55 Weather cov.....SCH SCH SCH SCH SCH SCH CHC CHC CHC CHC CHC CHC Weather type....RW RW RW RW RW RW RW RW RW RW RW RW Tstm cov........SCH SCH SCH SCH SCH SCH CHC CHC CHC CHC CHC CHC CWR.............10 10 10 10 10 10 20 20 20 20 20 20 Chc of thdr (%).20 20 20 20 20 20 30 30 30 30 30 30 Temp............92 91 89 84 81 79 77 76 75 73 71 70 RH..............29 30 35 40 44 49 53 52 52 53 55 56 20 FT wind dir..N N N SE SE SE SW SW SW SW SW SW 20 FT wind spd..5 5 5 5 5 5 10 10 10 10 10 10 20 FT wind gust.10 10 10 10 10 10 15 15 15 Ridge wind dir..NW W W W SW SW SW SW SW SW SW SW Ridge wind spd..10 10 15 15 15 15 15 15 20 20 20 15 Mix hgt (kft)...8.0 7.0 3.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Transp wind dir.NW W SE SE S S S SW W W NW NW Transp wind spd.10 10 5 10 10 10 10 10 10 10 10 10 .SUNDAY... Sky/weather.........Sunny (15-25 percent). CWR.................5 percent. Chance of thunder...5 percent. Max temperature.....92-97. Min humidity........13-18 percent. Wind (20 ft)........ Slope/valley.......Northwest winds around 10 mph. Ridgetop...........West 15 to 20 mph. Mixing height.......8000 ft AGL increasing to 12500 ft AGL late in the afternoon. Transport winds.....Northwest 10 to 15 mph shifting to the west around 20 mph late in the afternoon. TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........32 32 32 13 13 13 5 5 5 5 3 3 Weather cov..... Weather type.... Tstm cov........ CWR.............10 10 10 10 10 10 0 0 0 0 0 0 Chc of thdr (%).0 0 0 0 0 0 10 10 10 10 10 10 Temp............70 72 75 78 82 85 88 90 91 92 93 94 RH..............56 52 46 40 34 29 25 22 20 19 18 17 20 FT wind dir..W W W NW NW NW NW NW NW NW NW NW 20 FT wind spd..10 10 10 10 10 10 10 10 10 10 10 10 20 FT wind gust.15 15 15 15 15 15 15 15 15 20 20 20 Ridge wind dir..SW SW W W W W W W W W W W Ridge wind spd..15 15 15 15 15 20 20 20 20 20 20 20 Mix hgt (kft)...0.5 0.5 1.5 2.0 2.5 3.5 4.5 5.5 8.0 8.0 13 11 Transp wind dir.NW W W NW NW NW NW W W W W W Transp wind spd.10 15 15 15 15 15 15 15 20 20 20 20 $$ Forecaster...Moldan Requested by...Lewistown Dispatch Type of request...WILDFIRE .TAG 2617659.0/TFX .DELDT 07/18/26 .FormatterVersion 2.0.0 .EMAIL mtlec@firenet.gov, tfx.ops@noaa.gov