FNUS75 KMSO 201138 FWSMSO Spot Forecast for Lower Blackfoot Corridor F4 National Weather Service Missoula MT 538 AM MDT Mon Apr 20 2026 Forecast is based on ignition time of 0600 MDT on April 20. If conditions become unrepresentative...contact the National Weather Service. .DISCUSSION...A strong ridge of high pressure will be the dominate weather feature for the entire forecast period. This will translate to warm and dry conditions, with high temperatures running about 25 degrees above normal for this time of the year. confidence is high MinRH values will run in the upper teens to low 20 percent range today and Tuesday. RH values are likely to drop below 20 percent between 1500 and 1800 local today and Tuesday. Tuesday will be the warmest and driest day of the week, tho there is a 10 percent probability for isolated thunderstorms between 1800 and 2100 local. Winds will .TODAY... * Sky/Weather.........Mostly sunny. * CWR (> 0.10 Inch)...0 percent. * Chance Lightning....0 percent. * Max Temperature.....74-79. * Min Humidity........18-23 percent. * Wind (20 ft)........Variable 1-3 mph. * Mixing Height.......3500 ft agl increasing to 8000 ft agl. * Mixing Winds........North 5 mph shifting to the east 5 mph in the morning, then shifting to the south 5 mph late in the morning shifting to the west 15 mph late in the afternoon. * Precip Amount.......0.00 inches. TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........39 30 10 6 5 7 14 12 26 31 42 45 Weather cov..... Weather type.... Tstm cov........ CWR.............0 0 0 0 0 0 0 0 0 0 0 0 Chc of ltng (%).0 0 0 0 0 0 0 0 0 0 0 0 Temp............38 37 41 44 52 58 64 69 72 74 75 76 RH..............74 74 69 65 56 47 37 27 20 19 18 18 20 FT wind dir..N N N N N E E N W W W W 20 FT wind spd..1 1 0 0 0 1 1 1 2 3 2 2 20 FT wind gust.5 5 5 5 5 5 10 10 10 10 Mix hgt (kft)...1.5 1.5 1.5 1.5 2.5 3.0 3.5 4.5 6.0 7.5 8.0 8.0 Transp wind dir.N E E SE SE S SW SW W W W W Transp wind spd.5 5 5 5 5 5 5 5 10 10 15 10 .TONIGHT... * Sky/Weather.........Partly cloudy. * CWR (> 0.10 Inch)...0 percent. * Chance Lightning....0 percent. * Min Temperature.....39-44. * Max Humidity........62-67 percent. * Wind (20 ft)........Variable 1-3 mph. * Mixing Height.......6000 ft agl decreasing to 1500 ft agl. * Mixing Winds........West 10 mph shifting to the northeast 5 mph late in the evening. * Precip Amount.......0.00 inches. TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM Sky (%).........40 31 33 45 42 42 39 22 27 25 41 37 Weather cov..... Weather type.... Tstm cov........ CWR.............0 0 0 0 0 0 0 0 0 0 0 0 Chc of ltng (%).0 0 0 0 0 0 0 0 0 0 0 0 Temp............74 71 67 60 57 54 51 49 47 45 44 43 RH..............20 22 36 43 46 49 52 53 55 58 60 64 20 FT wind dir..W NW N N N N N N N NE N NE 20 FT wind spd..2 2 1 1 0 0 0 0 1 1 1 1 20 FT wind gust.10 10 5 5 5 5 5 5 5 5 5 5 Mix hgt (kft)...6.0 2.0 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 Transp wind dir.W W NW N N NE NE NE NE E NE NE Transp wind spd.10 5 5 5 5 5 5 5 5 5 5 5 .TUESDAY... * Sky/Weather.........Partly cloudy. * CWR (>0.10 Inch)...0 percent. * Chance Lightning....0 percent. * Max Temperature.....80-85. * Min Humidity........14-19 percent. * Wind (20 ft)........Variable 1-3 mph, becoming southwest 5-7 mph in the afternoon. * Mixing Height.......3500 ft agl increasing to 11000 ft agl. * Mixing Winds........East 5 mph shifting to the southeast 10 mph late in the morning, then increasing to south 20 mph late in the afternoon. * Precip Amount.......0.00 inches. TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........36 36 36 33 33 33 20 20 20 38 38 38 Weather cov..... Weather type.... Tstm cov........ CWR.............0 0 0 0 0 0 0 0 0 0 0 0 Chc of ltng (%).0 0 0 0 0 0 0 0 0 0 0 0 Temp............41 43 46 50 57 65 72 77 80 81 82 81 RH..............67 63 60 57 49 39 30 24 21 19 17 16 20 FT wind dir..N N N E E E SE SE SE SW SW SW 20 FT wind spd..1 1 1 1 1 1 2 2 2 3 3 3 20 FT wind gust.5 5 5 5 5 5 5 5 5 10 10 10 Mix hgt (kft)...1.5 1.5 1.5 2.0 2.0 2.5 3.5 6.0 8.5 11 11 11 Transp wind dir.NE NE E E E SE SE S S S S SW Transp wind spd.5 5 5 5 5 5 5 10 15 15 20 15 TUESDAY NIGHT... * Sky/Weather.........Partly cloudy. * CWR (> 0.10 Inch)...0 percent. * Chance Lightning....0 percent. * Min Temperature.....41-46. * Max Humidity........75-80 percent. * Wind (20 ft)........Variable 1-3 mph. * Mixing Height.......7000 ft agl decreasing to 1000 ft agl. * Mixing Winds........Southwest 15 mph shifting to the west 10 mph early in the evening, then shifting to the north 10 mph late in the evening becoming 10 mph after 3 am. * Precip Amount.......0.00 inches. TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM Sky (%).........41 41 41 59 59 59 64 64 64 47 47 47 Weather cov..... Weather type.... Tstm cov........ CWR.............0 0 0 0 0 0 0 0 0 0 0 0 Chc of ltng (%).10 10 10 10 10 10 0 0 0 0 0 0 Temp............78 74 68 63 60 58 56 53 50 48 45 44 RH..............19 25 32 39 45 52 57 62 65 69 74 78 20 FT wind dir..SW SW SW NW NW NW NW NW NW N N N 20 FT wind spd..2 2 2 1 1 1 1 1 1 1 1 1 20 FT wind gust.10 10 10 5 5 5 5 5 5 5 5 5 Mix hgt (kft)...9.5 7.0 4.0 1.5 1.0 1.0 1.5 1.5 1.5 1.5 1.5 1.5 Transp wind dir.SW SW W W NW NW N N N NE N N Transp wind spd.15 15 10 5 5 10 10 10 10 10 10 5 $$ Forecaster...Robinson Requested by...Daniel Sullivan Type of request...PRESCRIBED .TAG 2610627.1/MSO .DELDT 04/20/26 .FormatterVersion 2.0.0 .EMAIL stryker.clark@usda.gov,theoden.m.johnson@usda.gov,daniel.sullivan@usda.gov,sean.rivera@usda.gov