American Falls, ID climate
American Falls has chilly, snowy winters and warm summers, with very little rain. A typical July afternoon reaches 88°, a January night drops to 16°, and about 35 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in American Falls feels like
Winter
Spring
Summer
Fall
American Falls 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 | 33° | 16° | 1.2" | 9.4" | 10 | 21 | 16° – 33° |
| February | 38° | 19° | 0.9" | 7.2" | 8 | 15 | 19° – 38° |
| March | 50° | 27° | 1.2" | 3.2" | 8 | 3 | 32° – 43° |
| April | 58° | 32° | 1.3" | 2.5" | 8 | 0 | 41° – 50° |
| May | 68° | 39° | 1.5" | 0.5" | 7 | 0 | 48° – 60° |
| June | 78° | 46° | 1.0" | 0 | 5 | 0 | 57° – 68° |
| July | 88° | 52° | 0.4" | 0 | 3 | 0 | 60° – 76° |
| August | 87° | 51° | 0.6" | 0 | 4 | 0 | 64° – 72° |
| September | 77° | 42° | 0.9" | 0.1" | 4 | 0 | 55° – 63° |
| October | 61° | 32° | 1.0" | 1.1" | 6 | 0 | 39° – 54° |
| November | 46° | 23° | 1.0" | 3.0" | 7 | 3 | 27° – 42° |
| December | 34° | 16° | 1.2" | 7.9" | 10 | 16 | 20° – 31° |
| Year | 60° | 33° | 12.2" | 34.9" | 79 | 59 |
“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 American Falls
American Falls gets 12 inches of rain and melted snow a year. May is the wettest month and July the driest. Rain or snow falls on about 79 days a year. Snow covers the ground about 59 days of the year.
About 155 frost-free days a year
In half of years the last 32° night comes by May 4 and the first one by October 8. That leaves about 155 frost-free days for gardens, shorter than 76% of U.S. towns.
Heating and cooling a home in American Falls
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In American Falls, 91% of that work is heating and 9% 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 American Falls 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 American Falls averaged 0.9° warmer than the 1900s. The biggest change is in March (+2.6°). The shift is smaller than in 77% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at American Falls’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 19° to 38°. September is the most reliable, staying within 8°.
Common questions about American Falls’s climate
What is the coldest month in American Falls?
January, with a typical high of 33° and a low of 16°.
What is the hottest month in American Falls?
July, with a typical high of 88° and a low of 52°. About 42 days a year reach 90°.
How much snow does American Falls get?
About 35 inches in a normal winter, most of it in January.
When is the first frost in American Falls?
In half of years the first 32° night comes by October 8, and the last spring frost by May 4.
What is the rainiest month in American Falls?
May, with 1.5 inches of rain and melted snow. The year totals 12 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for American Falls itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at American Falls 6 Ne, ID (5 mi, snow) and American Falls, ID (3 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.