Helena West Side, MT climate
Helena West Side has cold, snowy winters and warm summers, with very little rain. A typical July afternoon reaches 84°, a January night drops to 14°, and about 37 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Helena West Side feels like
Winter
Spring
Summer
Fall
Helena West Side 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 | 34° | 14° | 0.4" | 6.6" | 7 | 18 | 14° – 32° |
| February | 37° | 16° | 0.5" | 6.6" | 7 | 11 | 10° – 36° |
| March | 47° | 23° | 0.8" | 4.6" | 7 | 5 | 24° – 43° |
| April | 55° | 30° | 1.4" | 2.9" | 9 | 1 | 37° – 48° |
| May | 65° | 38° | 2.2" | 0.1" | 11 | 0 | 46° – 56° |
| June | 73° | 45° | 2.5" | 0 | 12 | 0 | 54° – 66° |
| July | 84° | 51° | 1.2" | 0 | 8 | 0 | 57° – 74° |
| August | 83° | 49° | 1.1" | 0.3" | 6 | 0 | 60° – 70° |
| September | 72° | 41° | 1.2" | 0.2" | 6 | 0 | 52° – 61° |
| October | 57° | 31° | 1.1" | 2.8" | 7 | 2 | 37° – 51° |
| November | 42° | 22° | 0.8" | 5.4" | 7 | 6 | 24° – 41° |
| December | 33° | 15° | 0.5" | 7.7" | 7 | 14 | 14° – 30° |
| Year | 57° | 31° | 13.6" | 37.2" | 91 | 57 |
“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 Helena West Side
Helena West Side gets 14 inches of rain and melted snow a year. June is the wettest month and January the driest. Rain or snow falls on about 91 days a year. Snow covers the ground about 57 days of the year.
About 142 frost-free days a year
In half of years the last 32° night comes by May 9 and the first one by September 30. That leaves about 142 frost-free days for gardens, shorter than 88% of U.S. towns.
Heating and cooling a home in Helena West Side
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Helena West Side, 95% of that work is heating and 5% 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.
Helena West Side and its neighbors
Helena West Side borders 2 towns with climate data. January nights across them vary by 0.4°. Helena has the coldest January nights (15°) and Helena Valley West Central the hottest July afternoons (85°). Helena West Side’s January low is 14° and its July high 84°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Helena West Side 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 Helena West Side averaged 1.3° warmer than the 1900s. The biggest change is in January (+4.3°). The shift is larger than in 60% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Helena West Side’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 10° to 36°. September is the most reliable, staying within 9°.
Common questions about Helena West Side’s climate
What is the coldest month in Helena West Side?
January, with a typical high of 34° and a low of 14°.
What is the hottest month in Helena West Side?
July, with a typical high of 84° and a low of 51°. About 27 days a year reach 90°.
How much snow does Helena West Side get?
About 37 inches in a normal winter, most of it in December.
When is the first frost in Helena West Side?
In half of years the first 32° night comes by September 30, and the last spring frost by May 9.
What is the rainiest month in Helena West Side?
June, with 2.5 inches of rain and melted snow. The year totals 14 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Helena West Side itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Helena Rgnl Airport, MT (7 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.