Onarga, IL climate
Onarga has chilly winters and warm summers. A typical July afternoon reaches 85°, a January night drops to 17°, and about 25 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decade10° warmer than normal today. The forecast high is 82°, and a typical Oct 1 in Onarga peaks around 72°.Live forecast: National Weather Service · Normal: NOAA 1991–2020
What a year in Onarga feels like
Winter
Spring
Summer
Fall
Onarga 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° | 17° | 2.2" | 6.7" | 11 | 12 | 16° – 38° |
| February | 38° | 21° | 1.9" | 8.0" | 10 | 11 | 17° – 40° |
| March | 50° | 30° | 2.5" | 3.1" | 12 | 2 | 33° – 55° |
| April | 63° | 39° | 3.7" | 0.2" | 13 | 0 | 43° – 57° |
| May | 74° | 51° | 4.4" | 0 | 14 | 0 | 56° – 70° |
| June | 83° | 60° | 4.8" | 0 | 14 | 0 | 67° – 75° |
| July | 85° | 63° | 4.4" | 0 | 11 | 0 | 69° – 80° |
| August | 83° | 61° | 3.6" | 0 | 10 | 0 | 67° – 79° |
| September | 79° | 54° | 3.2" | 0 | 10 | 0 | 61° – 71° |
| October | 66° | 42° | 3.2" | 0 | 12 | 0 | 50° – 59° |
| November | 50° | 32° | 2.8" | 0.6" | 12 | 0 | 34° – 49° |
| December | 38° | 22° | 2.2" | 6.6" | 13 | 8 | 16° – 41° |
| Year | 62° | 41° | 38.8" | 25.2" | 141 | 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 Onarga
Onarga gets 39 inches of rain and melted snow a year. June is the wettest month and February the driest. Rain or snow falls on about 141 days a year. Snow covers the ground about 33 days of the year.
About 174 frost-free days a year
In half of years the last 32° night comes by April 24 and the first one by October 16. That leaves about 174 frost-free days for gardens, shorter than 56% of U.S. towns.
Heating and cooling a home in Onarga
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Onarga, 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.
Onarga and its neighbors
Onarga borders 4 towns with climate data. January nights across them vary by 0.3°. Crescent has the coldest January nights (17°) and Douglas the hottest July afternoons (85°). Onarga’s January low is 17° and its July high 85°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Onarga 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 Onarga averaged 1.2° warmer than the 1900s. The biggest change is in December (+2.4°). The shift is smaller than in 53% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Onarga’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 16° to 41°. June is the most reliable, staying within 8°.
Common questions about Onarga’s climate
What is the coldest month in Onarga?
January, with a typical high of 33° and a low of 17°.
What is the hottest month in Onarga?
July, with a typical high of 85° and a low of 63°. About 16 days a year reach 90°.
How much snow does Onarga get?
About 25 inches in a normal winter, most of it in February.
When is the first frost in Onarga?
In half of years the first 32° night comes by October 16, and the last spring frost by April 24.
What is the rainiest month in Onarga?
June, 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 Onarga itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Milford 5nw, IL (11 mi, snow) and Watseka 2 Nw, IL (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.