Missoula, MT weather in May
May in Missoula: mild, with frequent rain. Highs 66°F, lows 40°F, about 12 wet days.
- Normal high
- 66°F
- Normal low
- 40°F
- Wet days
- 12
- 1.8 in total
- Muggy days
- 0
- dew point 65°F+
How May changes from start to finish
| May 1 | May 31 | |
|---|---|---|
| Normal high | 61°F | 70°F |
| Normal low | 35°F | 44°F |
| Chance of a wet day | 37% | 43% |
| Sunrise / sunset | 6:20 am / 8:45 pm | 5:45 am / 9:21 pm |
| Daylight | 14.4 h | 15.6 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Mountain Time).
A typical May day
- 6 am43°Fdew point 37°F
- 9 am52°Fdew point 38°F
- Noon60°Fdew point 38°F
- 3 pm64°Fdew point 36°F
- 6 pm62°Fdew point 36°F
- 9 pm54°Fdew point 38°F
NOAA hourly normals (local standard time) from Missoula Intl Airport (6 mi away); average wind 6 mph.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F14 of 31
- Hot dayshigh 90°F or more0 of 31
- Muggy daysdaily mean dew point 65°F or more0 of 31
- Wet daysat least 0.01 in of rain or melted snow12 of 31
- Notable rainat least 0.10 in5 of 31
- Freezing nightslow 32°F or below4 of 31
- Snow on the groundsnow depth 1 in or more0 of 31
Average days per May, counted from daily records for each year 1991-2020.
Rain and snow in May
Normal precipitation is 1.8 in; a dry May brings about 1.3 in and a wet one about 2.3 in (25th and 75th percentiles). About 1 day brings half an inch or more. Normal snowfall is 0.3 in.
How May varies from year to year
- Warmest May, 1991-20201993: average high 73°F
- Coolest May1996: average high 59°F
- Wettest May2004: 3.9 in
- Driest May2001: 0.4 in
- Highest reading92°F (May 30, 2020)
- Lowest reading21°F (May 8, 1999)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
May compared with April and June
| April | May | June | |
|---|---|---|---|
| Normal high | 56°F | 66°F | 73°F |
| Normal low | 32°F | 40°F | 46°F |
| Wet days | 11 | 12 | 13 |
| Comfortable days | 6 | 14 | 15 |
| Daylight | 13.6 h | 15.1 h | 15.8 h |
Highs change by +10°F from April and +7°F into June.
Nearby alternatives in May
- Warmer: Boise, ID249 mi · high 72°F · 8 wet days
- Drier: Sun Valley, ID220 mi · high 62°F · 8 wet days
- Cooler: Big Sky, MT167 mi · high 58°F · 14 wet days
How Missoula ranks in May
- Normal high328th warmest of 378 cities; 2nd of 6 in Montana
- Wet days276th driest of 378
- Comfortable days126th most of 339
What to pack for Missoula in May
- A warm jacket – lows near 40°F, highs near 66°F
- Layers – afternoons near 66°F but nights near 40°F
- A rain jacket or umbrella – rain on about 12 days
Frost in May
The last spring frost typically comes around May 10; in 1 year in 10 it comes after May 28. All frost dates for Missoula.
Heating and cooling
May has 375 heating degree days and 3 cooling degree days (base 65°F), 5% of the year's total heating and cooling demand.
Questions
How cold is Missoula in May?
The normal high is 66°F and the normal low is 40°F. From 1991 to 2020 the coldest May reading was 21°F (May 8, 1999).
Does it rain a lot in Missoula in May?
About 12 days in May have at least 0.01 in of precipitation, and the normal total is 1.8 in. The wettest May in 1991-2020 was in 2004 (3.9 in); the driest was in 2001 (0.4 in).
Does it snow in Missoula in May?
Yes. Normal snowfall in May is 0.3 in.
Is May a good time to visit Missoula?
May ranks 1st of 12 months on our comfort score for Missoula (74 out of 100). It has about 14 comfortable days. The best months are May and June.
Where the numbers come from
- Temperature, rain, snowfall, snow depth and humidity and wind by hour: Missoula Intl Airport (USW00024153), 5.7 mi NW of the city center, 3,192 ft . NOAA normals and daily records, 1991-2020.
- Frost dates: Missoula 2 Ne (USC00245735), 2.2 mi NE of the city center, 3,420 ft (212 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Missoula International Airport (727730-24153), 5.8 mi NW of the city center, 3,195 ft . Hourly observations, 1991-2020.
- Not available for this location: cloud cover (no station close enough or similar enough in elevation).