Challis, ID climate
Challis has cold winters and warm summers, with very little rain. A typical July afternoon reaches 87°, a January night drops to 12°.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Challis feels like
Winter
Spring
Summer
Fall
Challis weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | 30-yr range |
|---|---|---|---|---|
| January | 32° | 12° | 0.5" | 13° – 28° |
| February | 38° | 16° | 0.4" | 21° – 34° |
| March | 49° | 24° | 0.6" | 32° – 42° |
| April | 57° | 30° | 0.7" | 38° – 49° |
| May | 67° | 38° | 1.1" | 46° – 59° |
| June | 76° | 45° | 1.2" | 55° – 67° |
| July | 87° | 51° | 0.6" | 59° – 74° |
| August | 85° | 49° | 0.6" | 61° – 71° |
| September | 76° | 41° | 0.7" | 54° – 62° |
| October | 60° | 31° | 0.6" | 37° – 52° |
| November | 42° | 21° | 0.5" | 25° – 39° |
| December | 31° | 11° | 0.7" | 13° – 26° |
| Year | 58° | 31° | 8.0" |
“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 Challis
Challis gets 8 inches of rain and melted snow a year. June is the wettest month and February the driest.
About 131 frost-free days a year
In half of years the last 32° night comes by May 14 and the first one by September 25. That leaves about 131 frost-free days for gardens, shorter than 94% of U.S. towns.
Heating and cooling a home in Challis
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Challis, 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 Challis 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 Challis averaged 1.7° warmer than the 1900s. The biggest change is in January (+3.3°). The shift is larger than in 79% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Challis’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. January swings the most: between 1991 and 2020 its average temperature ranged from 13° to 28°. September is the most reliable, staying within 8°.
Common questions about Challis’s climate
What is the coldest month in Challis?
December, with a typical high of 31° and a low of 11°.
What is the hottest month in Challis?
July, with a typical high of 87° and a low of 51°. About 28 days a year reach 90°.
When is the first frost in Challis?
In half of years the first 32° night comes by September 25, and the last spring frost by May 14.
What is the rainiest month in Challis?
June, with 1.2 inches of rain and melted snow. The year totals 8 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Challis itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Challis Airport, ID (1 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.