Bloomington, ID climate
Bloomington has cold, snowy winters and warm summers, with very little rain. A typical July afternoon reaches 84°, a January night drops to 8°, and about 37 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Bloomington feels like
Winter
Spring
Summer
Fall
Bloomington 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 | 30° | 8° | 1.4" | 9.1" | 8 | 29 | 12° – 27° |
| February | 34° | 10° | 1.3" | 8.8" | 9 | 26 | 15° – 32° |
| March | 43° | 20° | 1.2" | 4.1" | 9 | 19 | 25° – 38° |
| April | 53° | 27° | 1.5" | 2.7" | 9 | 3 | 33° – 46° |
| May | 64° | 35° | 2.0" | 0.2" | 10 | 0 | 43° – 54° |
| June | 74° | 41° | 1.2" | 0 | 6 | 0 | 52° – 63° |
| July | 84° | 47° | 0.6" | 0 | 4 | 0 | 56° – 70° |
| August | 83° | 45° | 0.9" | 0 | 5 | 0 | 59° – 67° |
| September | 73° | 37° | 1.2" | 0.1" | 6 | 0 | 51° – 59° |
| October | 58° | 28° | 1.4" | 1.1" | 7 | 1 | 34° – 49° |
| November | 42° | 19° | 1.1" | 4.1" | 8 | 7 | 23° – 37° |
| December | 31° | 10° | 1.4" | 7.2" | 8 | 22 | 15° – 27° |
| Year | 56° | 27° | 15.2" | 37.4" | 89 | 107 |
“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 Bloomington
Bloomington gets 15 inches of rain and melted snow a year. May is the wettest month and July the driest. Rain or snow falls on about 89 days a year. Snow covers the ground about 107 days of the year.
About 123 frost-free days a year
In half of years the last 32° night comes by May 19 and the first one by September 21. That leaves about 123 frost-free days for gardens, shorter than 97% of U.S. towns.
Heating and cooling a home in Bloomington
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Bloomington, 99% of that work is heating and 1% 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 Bloomington 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 Bloomington averaged 1.7° warmer than the 1900s. The biggest change is in March (+3.8°). The shift is larger than in 80% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Bloomington’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 15° to 32°. August is the most reliable, staying within 8°.
Common questions about Bloomington’s climate
What is the coldest month in Bloomington?
January, with a typical high of 30° and a low of 8°.
What is the hottest month in Bloomington?
July, with a typical high of 84° and a low of 47°. About 5 days a year reach 90°.
How much snow does Bloomington get?
About 37 inches in a normal winter, most of it in January.
When is the first frost in Bloomington?
In half of years the first 32° night comes by September 21, and the last spring frost by May 19.
What is the rainiest month in Bloomington?
May, with 2.0 inches of rain and melted snow. The year totals 15 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Bloomington itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Lifton Pumping Stn, ID (7 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.