Gilson, IL climate
Gilson has chilly winters and warm summers. A typical July afternoon reaches 85°, a January night drops to 16°, and about 25 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Gilson feels like
Winter
Spring
Summer
Fall
Gilson 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 | 32° | 16° | 1.8" | 6.4" | 9 | 14 | 16° – 36° |
| February | 37° | 20° | 1.9" | 7.7" | 9 | 11 | 15° – 39° |
| March | 50° | 29° | 2.4" | 3.4" | 10 | 3 | 32° – 54° |
| April | 63° | 39° | 3.8" | 0.4" | 12 | 0 | 42° – 58° |
| May | 73° | 51° | 5.0" | 0 | 14 | 0 | 56° – 70° |
| June | 82° | 61° | 4.6" | 0 | 12 | 0 | 68° – 76° |
| July | 85° | 64° | 4.1" | 0 | 10 | 0 | 69° – 81° |
| August | 83° | 62° | 3.6" | 0 | 10 | 0 | 67° – 78° |
| September | 78° | 54° | 3.6" | 0 | 8 | 0 | 60° – 71° |
| October | 65° | 42° | 3.0" | 0.2" | 10 | 0 | 48° – 59° |
| November | 50° | 31° | 2.6" | 1.4" | 8 | 1 | 33° – 50° |
| December | 37° | 21° | 2.1" | 5.9" | 9 | 9 | 14° – 39° |
| Year | 61° | 41° | 38.3" | 25.4" | 119 | 38 |
“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 Gilson
Gilson gets 38 inches of rain and melted snow a year. May is the wettest month and January the driest. Rain or snow falls on about 119 days a year. Snow covers the ground about 38 days of the year.
About 181 frost-free days a year
In half of years the last 32° night comes by April 21 and the first one by October 20. That leaves about 181 frost-free days for gardens, longer than 54% of U.S. towns.
Heating and cooling a home in Gilson
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Gilson, 87% of that work is heating and 13% 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 Gilson 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 Gilson averaged 0.7° warmer than the 1900s. The biggest change is in December (+1.9°). The shift is smaller than in 88% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Gilson’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 14° to 39°. June is the most reliable, staying within 7°.
Common questions about Gilson’s climate
What is the coldest month in Gilson?
January, with a typical high of 32° and a low of 16°.
What is the hottest month in Gilson?
July, with a typical high of 85° and a low of 64°. About 13 days a year reach 90°.
How much snow does Gilson get?
About 25 inches in a normal winter, most of it in February.
When is the first frost in Gilson?
In half of years the first 32° night comes by October 20, and the last spring frost by April 21.
What is the rainiest month in Gilson?
May, with 5.0 inches of rain and melted snow. The year totals 38 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Gilson itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Knoxville, IL (5 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.