Grass Range, MT climate
Grass Range has cold, snowy winters and pleasant summers, with very little rain. A typical July afternoon reaches 84°, a January night drops to 12°, and about 50 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Grass Range feels like
Winter
Spring
Summer
Fall
Grass Range weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 35° | 12° | 0.6" | 8.7" | 6 | 17 | 13° – 35° |
| February | 38° | 14° | 0.5" | 7.8" | 6 | 13 | 3° – 38° |
| March | 48° | 22° | 0.8" | 9.2" | 7 | 8 | 19° – 43° |
| April | 56° | 30° | 1.8" | 4.8" | 8 | 2 | 37° – 47° |
| May | 65° | 39° | 3.2" | 0.9" | 12 | 0 | 48° – 57° |
| June | 74° | 47° | 3.1" | 0 | 12 | 0 | 56° – 66° |
| July | 84° | 53° | 1.6" | 0 | 9 | 0 | 59° – 75° |
| August | 83° | 52° | 1.3" | 0 | 7 | 0 | 61° – 73° |
| September | 73° | 43° | 1.4" | 0.1" | 6 | 0 | 53° – 64° |
| October | 58° | 32° | 1.2" | 3.4" | 7 | 1 | 37° – 50° |
| November | 45° | 21° | 0.7" | 6.4" | 5 | 8 | 22° – 42° |
| December | 36° | 14° | 0.6" | 8.8" | 5 | 15 | 13° – 34° |
| Year | 58° | 32° | 16.8" | 50.1" | 88 | 64 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Grass Range
Grass Range gets 17 inches of rain and melted snow a year. May is the wettest month and February the driest. Rain or snow falls on about 88 days a year. Snow covers the ground about 64 days of the year.
About 126 frost-free days a year
In half of years the last 32° night comes by May 20 and the first one by September 24. That leaves about 126 frost-free days for gardens, shorter than 96% of U.S. towns.
Heating and cooling a home in Grass Range
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Grass Range, 96% of that work is heating and 4% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
How Grass Range compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Grass Range averaged 1.6° warmer than the 1900s. The biggest change is in January (+4.7°). The shift is larger than in 76% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Grass Range’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 3° to 38°. June is the most reliable, staying within 9°.
Common questions about Grass Range’s climate
What is the coldest month in Grass Range?
January, with a typical high of 35° and a low of 12°.
What is the hottest month in Grass Range?
July, with a typical high of 84° and a low of 53°. About 14 days a year reach 90°.
How much snow does Grass Range get?
About 50 inches in a normal winter, most of it in March.
When is the first frost in Grass Range?
In half of years the first 32° night comes by September 24, and the last spring frost by May 20.
What is the rainiest month in Grass Range?
May, with 3.2 inches of rain and melted snow. The year totals 17 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Grass Range itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Grass Range, MT (1 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.