Atlas, IL climate
Atlas has chilly winters and warm summers. A typical July afternoon reaches 87°, a January night drops to 20°, and about 10 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Atlas feels like
Winter
Spring
Summer
Fall
Atlas 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 | 37° | 20° | 2.0" | 5.1" | 7 | 6 | 22° – 40° |
| February | 43° | 24° | 1.9" | 1.0" | 7 | 3 | 22° – 44° |
| March | 54° | 33° | 2.8" | 0.8" | 9 | 1 | 36° – 57° |
| April | 66° | 43° | 4.1" | 0 | 10 | 0 | 47° – 61° |
| May | 75° | 54° | 4.8" | 0 | 12 | 0 | 59° – 74° |
| June | 84° | 63° | 4.6" | 0 | 10 | 0 | 69° – 78° |
| July | 87° | 67° | 4.1" | 0 | 8 | 0 | 72° – 84° |
| August | 86° | 64° | 3.4" | 0 | 7 | 0 | 70° – 81° |
| September | 80° | 56° | 3.4" | 0 | 7 | 0 | 62° – 74° |
| October | 68° | 45° | 3.1" | 0 | 8 | 0 | 50° – 62° |
| November | 54° | 34° | 2.6" | 0.4" | 7 | 1 | 37° – 52° |
| December | 42° | 25° | 2.1" | 2.6" | 7 | 2 | 19° – 42° |
| Year | 65° | 44° | 38.6" | 9.9" | 99 | 14 |
“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 Atlas
Atlas gets 39 inches of rain and melted snow a year. May is the wettest month and February the driest. Rain or snow falls on about 99 days a year. Snow covers the ground about 14 days of the year.
About 208 frost-free days a year
In half of years the last 32° night comes by April 4 and the first one by November 1. That leaves about 208 frost-free days for gardens, longer than 77% of U.S. towns.
Heating and cooling a home in Atlas
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Atlas, 80% of that work is heating and 20% is cooling.
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.
Atlas and its neighbors
Atlas borders 7 towns with climate data. January nights across them vary by 0.8°. Pittsfield has the coldest January nights (19°) and Ross the hottest July afternoons (88°). Atlas’s January low is 20° and its July high 87°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Atlas 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 Atlas averaged 0.9° warmer than the 1900s. The biggest change is in February (+2.0°). The shift is smaller than in 80% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Atlas’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. December swings the most: between 1991 and 2020 its average temperature ranged from 19° to 42°. June is the most reliable, staying within 9°.
Common questions about Atlas’s climate
What is the coldest month in Atlas?
January, with a typical high of 37° and a low of 20°.
What is the hottest month in Atlas?
July, with a typical high of 87° and a low of 67°. About 34 days a year reach 90°.
How much snow does Atlas get?
About 10 inches in a normal winter, most of it in January.
When is the first frost in Atlas?
In half of years the first 32° night comes by November 1, and the last spring frost by April 4.
What is the rainiest month in Atlas?
May, with 4.8 inches of rain and melted snow. The year totals 39 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Atlas itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Louisiana, MO (6 mi, snow) and Clarksville L&d 24, MO (13 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.