Dillon, IL climate
Dillon has chilly winters and warm summers. A typical July afternoon reaches 86°, a January night drops to 18°, and about 24 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Dillon feels like
Winter
Spring
Summer
Fall
Dillon 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 | 34° | 18° | 2.1" | 7.2" | 8 | 14 | 19° – 38° |
| February | 39° | 21° | 1.9" | 7.0" | 7 | 9 | 18° – 41° |
| March | 51° | 31° | 2.6" | 3.0" | 9 | 3 | 34° – 55° |
| April | 64° | 41° | 3.9" | 0.4" | 11 | 0 | 45° – 59° |
| May | 75° | 52° | 4.6" | 0 | 11 | 0 | 58° – 72° |
| June | 83° | 62° | 4.3" | 0 | 10 | 0 | 68° – 76° |
| July | 86° | 65° | 4.2" | 0 | 8 | 0 | 70° – 81° |
| August | 84° | 63° | 3.6" | 0 | 8 | 0 | 68° – 79° |
| September | 79° | 55° | 3.3" | 0 | 7 | 0 | 61° – 72° |
| October | 66° | 43° | 3.2" | 0 | 9 | 0 | 50° – 60° |
| November | 51° | 32° | 2.8" | 1.2" | 8 | 1 | 34° – 50° |
| December | 39° | 23° | 2.2" | 5.6" | 8 | 7 | 17° – 41° |
| Year | 63° | 42° | 38.8" | 24.4" | 103 | 33 |
“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 Dillon
Dillon 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 103 days a year. Snow covers the ground about 33 days of the year.
About 189 frost-free days a year
In half of years the last 32° night comes by April 16 and the first one by October 23. That leaves about 189 frost-free days for gardens, longer than 63% of U.S. towns.
Heating and cooling a home in Dillon
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Dillon, 83% of that work is heating and 17% 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.
Dillon and its neighbors
Dillon borders 4 towns with climate data. January nights across them vary by 0.5°. Elm Grove has the coldest January nights (17°) and Sand Prairie the hottest July afternoons (86°). Dillon’s January low is 18° and its July high 86°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Dillon 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 Dillon averaged 1.2° warmer than the 1900s. The biggest change is in December (+2.4°). The shift is smaller than in 56% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Dillon’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 17° to 41°. June is the most reliable, staying within 8°.
Common questions about Dillon’s climate
What is the coldest month in Dillon?
January, with a typical high of 34° and a low of 18°.
What is the hottest month in Dillon?
July, with a typical high of 86° and a low of 65°. About 23 days a year reach 90°.
How much snow does Dillon get?
About 24 inches in a normal winter, most of it in January.
When is the first frost in Dillon?
In half of years the first 32° night comes by October 23, and the last spring frost by April 16.
What is the rainiest month in Dillon?
May, with 4.6 inches of rain and melted snow. The year totals 39 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Dillon itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Mackinaw 3wsw, IL (9 mi, snow) and Peoria Gtr Peoria Airport, IL (17 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.