East Helena, MT climate
East Helena has cold, snowy winters and warm summers, with very little rain. A typical July afternoon reaches 85°, a January night drops to 15°, and about 37 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in East Helena feels like
Winter
Spring
Summer
Fall
East Helena 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° | 15° | 0.3" | 6.6" | 7 | 18 | 14° – 33° |
| February | 37° | 17° | 0.4" | 6.6" | 7 | 11 | 9° – 37° |
| March | 48° | 24° | 0.5" | 4.6" | 7 | 5 | 25° – 44° |
| April | 56° | 31° | 1.2" | 2.9" | 9 | 1 | 39° – 49° |
| May | 66° | 40° | 2.0" | 0.1" | 11 | 0 | 47° – 57° |
| June | 74° | 47° | 2.3" | 0 | 12 | 0 | 55° – 68° |
| July | 85° | 53° | 1.1" | 0 | 8 | 0 | 59° – 76° |
| August | 84° | 51° | 1.0" | 0.3" | 6 | 0 | 61° – 72° |
| September | 73° | 42° | 1.1" | 0.2" | 6 | 0 | 53° – 62° |
| October | 58° | 33° | 0.8" | 2.8" | 7 | 2 | 38° – 52° |
| November | 43° | 23° | 0.5" | 5.4" | 7 | 6 | 24° – 42° |
| December | 34° | 15° | 0.4" | 7.7" | 7 | 14 | 14° – 31° |
| Year | 58° | 33° | 11.6" | 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 East Helena
East Helena gets 12 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 East Helena
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In East Helena, 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.
East Helena and its neighbors
East Helena borders 2 towns with climate data. January nights across them vary by 0.3°. Helena has the coldest January nights (15°) and Helena Valley Southeast the hottest July afternoons (85°). East Helena’s January low is 15° and its July high 85°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How East Helena 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 East Helena averaged 1.2° warmer than the 1900s. The biggest change is in January (+4.1°). The shift is larger than in 50% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at East Helena’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 9° to 37°. September is the most reliable, staying within 9°.
Common questions about East Helena’s climate
What is the coldest month in East Helena?
January, with a typical high of 34° and a low of 15°.
What is the hottest month in East Helena?
July, with a typical high of 85° and a low of 53°. About 27 days a year reach 90°.
How much snow does East Helena get?
About 37 inches in a normal winter, most of it in December.
When is the first frost in East Helena?
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 East Helena?
June, with 2.3 inches of rain and melted snow. The year totals 12 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for East Helena itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Helena Rgnl Airport, MT (2 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.