FPUS55 KMSO 180623 ZFPMSO Zone Forecast Product National Weather Service Missoula MT 1223 AM MDT Mon May 18 2026 MTZ001-182200- Kootenai/Cabinet Region- Including the cities of Libby and Eureka 1223 AM MDT Mon May 18 2026 ...FROST ADVISORY IN EFFECT UNTIL 8 AM MDT THIS MORNING... .TODAY...Partly cloudy. Widespread frost and patchy fog early in the morning. Chance of rain showers and a slight chance of thunderstorms in the afternoon. Chance of precipitation 40 percent. Highs in the 60s. .TONIGHT...Partly cloudy. A 20 percent chance of rain in the evening. Areas of frost and patchy fog after midnight. Lows in the 30s to lower 40s. .TUESDAY...Partly cloudy. Areas of frost in the morning. Chance of rain showers and a slight chance of thunderstorms in the afternoon. Chance of precipitation 40 percent. Highs in the mid 60s to lower 70s. .TUESDAY NIGHT...Partly cloudy. Lows in the mid 30s to lower 40s. .WEDNESDAY...Mostly cloudy. Chance of rain showers and a slight chance of thunderstorms in the afternoon. Chance of precipitation 50 percent. Highs in the mid 60s to lower 70s. .WEDNESDAY NIGHT...Partly cloudy. A 20 percent chance of rain in the evening. Lows in the mid 30s to lower 40s. .THURSDAY...Mostly sunny. Highs in the upper 60s to mid 70s. .THURSDAY NIGHT...Mostly cloudy. A 20 percent chance of rain after midnight. Lows in the upper 30s to mid 40s. .FRIDAY...Partly cloudy. A 20 percent chance of rain in the afternoon. Highs in the 70s. .FRIDAY NIGHT...Partly cloudy. Lows in the 40s. .SATURDAY...Partly cloudy. Highs in the 70s to lower 80s. .SATURDAY NIGHT...Partly cloudy. Lows in the 40s. .SUNDAY...Mostly sunny. Highs in the 70s. $$ MTZ002-182200- West Glacier Region- Including the city of Swan Lake 1223 AM MDT Mon May 18 2026 .TODAY...Partly cloudy. Widespread frost early in the morning. Chance of rain showers, slight chance of thunderstorms and snow early in the afternoon. Chance of rain showers, slight chance of thunderstorms and snow showers late in the afternoon. Chance of precipitation 30 percent. Highs in the 50s. .TONIGHT...Partly cloudy. A 20 percent chance of rain in the evening. Widespread frost after midnight. Lows in the 30s. .TUESDAY...Mostly cloudy. Areas of frost in the morning. Chance of rain showers and a slight chance of thunderstorms in the afternoon. Chance of precipitation 50 percent. Highs in the 50s to lower 60s. Southwest winds to 15 mph. .TUESDAY NIGHT...Partly cloudy. Lows in the mid 30s to lower 40s. Southwest winds to 15 mph. .WEDNESDAY...A chance of rain in the morning, then rain showers likely and a slight chance of thunderstorms in the afternoon. Chance of precipitation 70 percent. Highs in the 50s to lower 60s. .WEDNESDAY NIGHT...Mostly cloudy with a chance of rain and snow in the evening, then partly cloudy with a slight chance of rain after midnight. Chance of precipitation 50 percent. Lows in the 30s. .THURSDAY...Partly cloudy. Highs in the upper 50s to mid 60s. .THURSDAY NIGHT...Partly cloudy in the evening then becoming mostly cloudy. Lows in the mid 30s to lower 40s. .FRIDAY...Mostly cloudy with a 30 percent chance of rain. Highs in the upper 50s to mid 60s. .FRIDAY NIGHT...Partly cloudy. Lows in the upper 30s to mid 40s. .SATURDAY...Partly cloudy. Highs in the 60s. .SATURDAY NIGHT...Partly cloudy. Lows in the 40s. .SUNDAY...Partly cloudy. Highs in the 60s to lower 70s. $$ MTZ003-182200- Flathead/Mission Valleys- Including the cities of Kalispell, Polson, and St. Ignatius 1223 AM MDT Mon May 18 2026 ...FROST ADVISORY IN EFFECT UNTIL 9 AM MDT THIS MORNING... .TODAY...Mostly sunny. Widespread frost early in the morning. Chance of rain showers and a slight chance of thunderstorms in the afternoon. Chance of precipitation 30 percent. Highs in the mid 50s to lower 60s. .TONIGHT...Partly cloudy. A 20 percent chance of rain in the evening. Areas of frost after midnight. Lows in the 30s. .TUESDAY...Mostly cloudy. Areas of frost in the morning. Chance of rain showers and a slight chance of thunderstorms in the afternoon. Chance of precipitation 40 percent. Highs in the 60s. .TUESDAY NIGHT...Partly cloudy. Lows in the mid 30s to lower 40s. .WEDNESDAY...Rain showers likely and a slight chance of thunderstorms in the afternoon. Chance of precipitation 60 percent. Highs in the 60s. .WEDNESDAY NIGHT...Mostly cloudy with a 50 percent chance of rain in the evening, then partly cloudy after midnight. Lows in the mid 30s to lower 40s. .THURSDAY...Partly cloudy. Highs in the 60s. .THURSDAY NIGHT...Partly cloudy in the evening then becoming mostly cloudy. Lows in the upper 30s to mid 40s. .FRIDAY...Partly cloudy. A 30 percent chance of rain in the afternoon. Highs in the mid 60s to lower 70s. .FRIDAY NIGHT...Partly cloudy. Lows in the 40s. .SATURDAY...Partly cloudy. Highs in the upper 60s to mid 70s. .SATURDAY NIGHT...Partly cloudy. Lows in the 40s. .SUNDAY...Partly cloudy. Highs in the 70s. $$ MTZ004-182200- Lower Clark Fork Region- Including the cities of Noxon, Thompson Falls, and Superior 1223 AM MDT Mon May 18 2026 ...FROST ADVISORY IN EFFECT UNTIL 8 AM MDT THIS MORNING... .TODAY...Partly cloudy. Widespread frost and areas of fog early in the morning. Chance of rain showers and a slight chance of thunderstorms in the afternoon. Chance of precipitation 30 percent. Highs in the mid 50s to lower 60s. .TONIGHT...Partly cloudy. A 20 percent chance of rain in the evening. Areas of frost after midnight. Lows in the 30s. .TUESDAY...Partly cloudy. Areas of frost in the morning. Highs in the 60s. .TUESDAY NIGHT...Partly cloudy. Lows in the mid 30s to lower 40s. .WEDNESDAY...Mostly cloudy. Chance of rain showers and a slight chance of thunderstorms in the afternoon. Chance of precipitation 30 percent. Highs in the 60s. .WEDNESDAY NIGHT...Mostly cloudy with a chance of rain showers and a slight chance of thunderstorms in the evening, then partly cloudy after midnight. Chance of precipitation 50 percent. Lows in the mid 30s to lower 40s. .THURSDAY...Partly cloudy. Highs in the mid 60s to lower 70s. .THURSDAY NIGHT...Mostly cloudy. Lows in the upper 30s to mid 40s. .FRIDAY...Partly cloudy. Highs in the mid 60s to lower 70s. .FRIDAY NIGHT...Partly cloudy. Lows in the upper 30s to mid 40s. .SATURDAY...Partly cloudy. Highs in the upper 60s to mid 70s. .SATURDAY NIGHT...Partly cloudy. Lows in the 40s. .SUNDAY...Mostly sunny. Highs in the upper 60s to mid 70s. $$ MTZ005-182200- Missoula/Bitterroot Valleys- Including the cities of Hamilton and Darby 1223 AM MDT Mon May 18 2026 ...FROST ADVISORY IN EFFECT UNTIL 9 AM MDT THIS MORNING... .TODAY...Partly cloudy. Widespread frost early in the morning. Slight chance of rain early in the afternoon. Slight chance of showers and thunderstorms late in the afternoon. Chance of precipitation 20 percent. Highs near 60. .TONIGHT...Partly cloudy. A 20 percent chance of rain in the evening. Widespread frost after midnight. Lows in the lower to mid 30s. .TUESDAY...Partly cloudy. Widespread frost in the morning. Highs in the lower to mid 60s. .TUESDAY NIGHT...Partly cloudy. Lows in the mid to upper 30s. .WEDNESDAY...Mostly cloudy. Chance of rain showers and a slight chance of thunderstorms in the afternoon. Chance of precipitation 30 percent. Highs in the mid to upper 60s. .WEDNESDAY NIGHT...Mostly cloudy. Chance of rain showers and a slight chance of thunderstorms in the evening, then slight chance of rain after midnight. Chance of precipitation 50 percent. Lows in the mid 30s to lower 40s. .THURSDAY...Partly cloudy. Highs in the mid to upper 60s. .THURSDAY NIGHT...Partly cloudy in the evening then becoming mostly cloudy. Lows near 40. .FRIDAY...Partly cloudy. Highs in the lower 70s. .FRIDAY NIGHT...Partly cloudy. Lows in the lower to mid 40s. .SATURDAY...Partly cloudy. Highs in the lower to mid 70s. .SATURDAY NIGHT...Partly cloudy. Lows in the lower to mid 40s. .SUNDAY...Mostly sunny. Highs in the mid to upper 70s. $$ MTZ006-182200- Bitterroot/Sapphire Mountains- Including the city of Sula 1223 AM MDT Mon May 18 2026 .TODAY...Partly cloudy. Widespread frost in the morning. Areas of rain and snow early in the afternoon. Chance of rain showers, slight chance of thunderstorms and snow late in the afternoon. Chance of precipitation 30 percent. Highs in the mid 40s to lower 50s. .TONIGHT...Partly cloudy. A 40 percent chance of rain in the evening. Widespread frost after midnight. Lows in the mid 20s to lower 30s. .TUESDAY...Partly cloudy. Widespread frost in the morning. Highs in the 50s to lower 60s. .TUESDAY NIGHT...Partly cloudy. Lows in the upper 20s to mid 30s. .WEDNESDAY...Partly cloudy. A 20 percent chance of showers and thunderstorms in the afternoon. Highs in the mid 50s to lower 60s. .WEDNESDAY NIGHT...Mostly cloudy. Chance of rain showers and a slight chance of thunderstorms in the evening. Chance of precipitation 50 percent. Lows in the 30s. .THURSDAY...Partly cloudy. Highs in the upper 50s to mid 60s. .THURSDAY NIGHT...Partly cloudy in the evening then becoming mostly cloudy. Lows in the 30s to lower 40s. .FRIDAY...Partly cloudy. Highs in the 60s. .FRIDAY NIGHT...Partly cloudy. Lows in the mid 30s to lower 40s. .SATURDAY...Partly cloudy. Highs in the upper 60s to mid 70s. .SATURDAY NIGHT...Partly cloudy. Lows in the mid 30s to lower 40s. .SUNDAY...Mostly sunny. Highs in the upper 60s to mid 70s. $$ MTZ007-182200- Butte/Blackfoot Region- Including the cities of Anaconda, Deer Lodge, and Drummond 1223 AM MDT Mon May 18 2026 .TODAY...Partly cloudy. Widespread frost in the morning. A 20 percent chance of rain and snow late in the afternoon. Highs in the mid 40s to lower 50s. North winds to 15 mph in the afternoon. .TONIGHT...Partly cloudy. Widespread frost after midnight. Lows in the mid 20s to lower 30s. .TUESDAY...Partly cloudy. Widespread frost in the morning. Highs in the mid 50s to lower 60s. .TUESDAY NIGHT...Partly cloudy. Lows in the upper 20s to mid 30s. .WEDNESDAY...Partly cloudy. A 20 percent chance of rain in the afternoon. Highs in the mid 50s to lower 60s. West winds to 15 mph. .WEDNESDAY NIGHT...Rain showers likely and a slight chance of thunderstorms in the evening, then a chance of rain and snow after midnight. Chance of precipitation 70 percent. Lows in the 30s. .THURSDAY...Partly cloudy. A 20 percent chance of rain in the morning. Highs in the mid 50s to lower 60s. .THURSDAY NIGHT...Partly cloudy in the evening then becoming mostly cloudy. Lows in the 30s. .FRIDAY...Partly cloudy. A 20 percent chance of rain in the afternoon. Highs in the 60s. .FRIDAY NIGHT...Partly cloudy. Lows in the mid 30s to lower 40s. .SATURDAY...Partly cloudy. Highs in the upper 60s to mid 70s. .SATURDAY NIGHT...Partly cloudy. Lows in the mid 30s to lower 40s. .SUNDAY...Partly cloudy. Highs in the upper 60s to mid 70s. $$ MTZ043-182200- Potomac/Seeley Lake Region- Including the cities of East Missoula, Seeley Lake, and Clinton 1223 AM MDT Mon May 18 2026 .TODAY...Partly cloudy. Widespread frost early in the morning. Areas of snow and a slight chance of rain early in the afternoon. Chance of rain showers, snow showers and a slight chance of thunderstorms late in the afternoon. Chance of precipitation 30 percent. Highs in the 50s. .TONIGHT...Partly cloudy. A 20 percent chance of rain in the evening. Widespread frost after midnight. Lows in the upper 20s to mid 30s. .TUESDAY...Partly cloudy. Widespreadfrost in the morning. Highs in the mid 50s to lower 60s. .TUESDAY NIGHT...Partly cloudy. Lows in the 30s. West winds to 15 mph. .WEDNESDAY...Mostly cloudy. Chance of rain showers and a slight chance of thunderstorms in the afternoon. Chance of precipitation 30 percent. Highs in the mid 50s to lower 60s. .WEDNESDAY NIGHT...Rain showers likely and a slight chance of thunderstorms in the evening, then partly cloudy with a slight chance of rain after midnight. Chance of precipitation 60 percent. Lows in the 30s. .THURSDAY...Partly cloudy. Highs in the upper 50s to mid 60s. .THURSDAY NIGHT...Partly cloudy in the evening then becoming mostly cloudy. Lows in the mid 30s to lower 40s. .FRIDAY...Partly cloudy. Highs in the 60s. .FRIDAY NIGHT...Partly cloudy. Lows in the upper 30s to mid 40s. .SATURDAY...Partly cloudy. Highs in the mid 60s to lower 70s. .SATURDAY NIGHT...Partly cloudy. Lows in the upper 30s to mid 40s. .SUNDAY...Partly cloudy. Highs in the upper 60s to mid 70s. $$ IDZ009-182200- Western Lemhi County- Including the city of Shoup 1223 AM MDT Mon May 18 2026 .TODAY...Mostly sunny. Widespread frost early in the morning. Highs in the 50s. .TONIGHT...Partly cloudy. Lows in the upper 20s to mid 30s. .TUESDAY...Partly cloudy. Highs in the upper 50s to mid 60s. .TUESDAY NIGHT...Mostly clear. Lows in the mid 30s to lower 40s. .WEDNESDAY...Partly cloudy. Highs in the upper 50s to mid 60s. .WEDNESDAY NIGHT...Partly cloudy. A 20 percent chance of showers and thunderstorms in the evening. Lows in the mid 30s to lower 40s. .THURSDAY...Partly cloudy. Highs in the 60s. .THURSDAY NIGHT...Partly cloudy in the evening then becoming mostly cloudy. Lows in the upper 30s to mid 40s. .FRIDAY...Partly cloudy. Highs in the mid 60s to lower 70s. .FRIDAY NIGHT...Partly cloudy. Lows in the upper 30s to mid 40s. .SATURDAY...Partly cloudy. Highs in the 70s. .SATURDAY NIGHT...Partly cloudy. Lows in the 40s. .SUNDAY...Mostly sunny. Highs in the 70s. $$ IDZ010-182200- Eastern Lemhi County- Including the cities of Salmon and Leadore 1223 AM MDT Mon May 18 2026 .TODAY...Mostly sunny. Widespread frost early in the morning. Highs in the upper 40s to mid 50s. North winds to 15 mph. .TONIGHT...Partly cloudy. Widespread frost after midnight. Lows in the mid 20s to lower 30s. North winds to 15 mph. .TUESDAY...Partly cloudy. Highs in the mid 50s to lower 60s. .TUESDAY NIGHT...Partly cloudy. Lows in the 30s. .WEDNESDAY...Partly cloudy. Highs in the upper 50s to mid 60s. .WEDNESDAY NIGHT...Mostly cloudy with a chance of rain showers and a slight chance of thunderstorms in the evening, then partly cloudy with a slight chance of rain after midnight. Chance of precipitation 30 percent. Lows in the 30s. .THURSDAY...Partly cloudy. Highs in the 60s. .THURSDAY NIGHT...Partly cloudy in the evening then becoming mostly cloudy. Lows in the mid 30s to lower 40s. .FRIDAY...Partly cloudy. Highs in the mid 60s to lower 70s. .FRIDAY NIGHT...Partly cloudy. Lows in the mid 30s to lower 40s. .SATURDAY...Partly cloudy. Highs in the 70s. .SATURDAY NIGHT...Partly cloudy. Lows in the upper 30s to mid 40s. .SUNDAY...Partly cloudy. Highs in the 70s to lower 80s. $$ IDZ005-182200- Northern Clearwater Mountains- Including the cities of Pierce and Elk River 1123 PM PDT Sun May 17 2026 .TODAY...Partly cloudy. Patchy fog early in the morning. Slight chance of rain early in the afternoon. Slight chance of showers and thunderstorms late in the afternoon. Chance of precipitation 20 percent. Highs in the mid 50s to lower 60s. .TONIGHT...Partly cloudy. A 20 percent chance of rain in the evening. Areas of frost and patchy fog after midnight. Lows in the upper 20s to mid 30s. .TUESDAY...Mostly sunny. Areas of frost and patchy fog in the morning. Highs in the 60s. .TUESDAY NIGHT...Partly cloudy. Lows in the 30s to lower 40s. .WEDNESDAY...Partly cloudy. Highs in the 60s. .WEDNESDAY NIGHT...Partly cloudy. Lows in the 30s to lower 40s. .THURSDAY...Mostly sunny. Highs in the mid 60s to lower 70s. .THURSDAY NIGHT...Partly cloudy in the evening then becoming mostly cloudy. Lows in the mid 30s to lower 40s. .FRIDAY...Partly cloudy. Highs in the upper 60s to mid 70s. .FRIDAY NIGHT...Partly cloudy. Lows in the mid 30s to lower 40s. .SATURDAY...Partly cloudy. Highs in the 70s. .SATURDAY NIGHT...Partly cloudy. Lows in the upper 30s to mid 40s. .SUNDAY...Partly cloudy. Highs in the upper 60s to mid 70s. $$ IDZ006-182200- Southern Clearwater Mountains- Including the cities of Powell, Elk City, and Dixie 1123 PM PDT Sun May 17 2026 .TODAY...Partly cloudy. Areas of fog and frost in the morning. Slight chance of rain early in the afternoon. Slight chance of showers and thunderstorms late in the afternoon. Chance of precipitation 20 percent. Highs 48 to 61. .TONIGHT...Partly cloudy. A 20 percent chance of rain in the evening. Widespread frost and areas of fog after midnight. Lows 27 to 41. .TUESDAY...Mostly sunny. Widespread frost and areas of fog in the morning. Highs 53 to 66. .TUESDAY NIGHT...Partly cloudy. Lows 31 to 46. .WEDNESDAY...Mostly cloudy. Highs 54 to 68. .WEDNESDAY NIGHT...Partly cloudy. A 20 percent chance of showers and thunderstorms in the evening. Lows 31 to 46. .THURSDAY...Mostly sunny. Highs 57 to 71. .THURSDAY NIGHT...Partly cloudy. Lows 33 to 47. .FRIDAY...Partly cloudy. Highs in the lower 60s to mid 70s. .FRIDAY NIGHT...Partly cloudy. Lows 34 to 48. .SATURDAY...Partly cloudy. Highs in the mid 60s to upper 70s. .SATURDAY NIGHT...Partly cloudy. Lows 35 to 50. .SUNDAY...Mostly sunny. Highs 65 to 78. $$ IDZ007-182200- Orofino/Grangeville Region- Including the city of Kooskia 1123 PM PDT Sun May 17 2026 .TODAY...Partly cloudy. Widespread frost early in the morning. Highs in the 50s to upper 60s. .TONIGHT...Partly cloudy. Lows in the mid 30s to lower 40s. .TUESDAY...Mostly sunny. Highs in the 60s to lower 70s. .TUESDAY NIGHT...Partly cloudy. Lows in the upper 30s to mid 40s. .WEDNESDAY...Partly cloudy. Highs in the mid 60s to lower 70s. .WEDNESDAY NIGHT...Partly cloudy. Lows in the 40s. .THURSDAY...Mostly sunny. Highs in the upper 60s to mid 70s. .THURSDAY NIGHT...Partly cloudy in the evening then becoming mostly cloudy. Lows in the 40s. .FRIDAY...Partly cloudy. Highs in the 60s to upper 70s. .FRIDAY NIGHT...Mostly clear. Lows in the 40s. .SATURDAY...Partly cloudy. Highs in the 70s to lower 80s. .SATURDAY NIGHT...Partly cloudy. Lows in the mid 40s to lower 50s. .SUNDAY...Mostly sunny. Highs in the 70s. $$ IDZ008-182200- Lower Hells Canyon/Salmon River Region- Including the cities of Riggins and White Bird 1123 PM PDT Sun May 17 2026 .TODAY...Mostly sunny. Areas of frost early in the morning. Highs in the mid 50s to upper 60s. North winds to 15 mph in the afternoon. .TONIGHT...Partly cloudy. Lows in the upper 30s to mid 40s. East winds to 15 mph. .TUESDAY...Mostly sunny. Highs in the lower 60s to mid 70s. .TUESDAY NIGHT...Partly cloudy. Lows in the 40s. .WEDNESDAY...Partly cloudy. Highs 63 to 76. North winds to 15 mph. .WEDNESDAY NIGHT...Partly cloudy. Lows in the 40s to lower 50s. .THURSDAY...Mostly sunny. Highs 65 to 78. .THURSDAY NIGHT...Partly cloudy. Lows in the mid 40s to lower 50s. .FRIDAY...Partly cloudy. Highs 68 to 81. .FRIDAY NIGHT...Mostly clear. Lows in the mid 40s to lower 50s. .SATURDAY...Mostly sunny. Highs 72 to 85. .SATURDAY NIGHT...Partly cloudy. Lows in the upper 40s to mid 50s. .SUNDAY...Mostly sunny. Highs 72 to 85. $$