Champaign, Illinois Weather
Thunder quiets the land. Day 93 of summer. Read this microseason across nine climate regions →
Champaign weather forecast — hour by hour, 7-day outlook, NOAA radar
Conditions updated 9:38 AM CDT · Open-Meteo
- TodaySep 21Overcast61%0.63″65°60°—
- TuesdaySep 22Overcast——63°57°-2°
- WednesdaySep 23Overcast——65°56°+2°
- ThursdaySep 24Overcast——68°56°+3°
- FridaySep 25Overcast——71°59°+3°
- SaturdaySep 26Light Drizzle—0.02″66°58°-5°
- SundaySep 27Drizzle——77°59°+11°
Air quality now AQI 23 · Good
AQI 23 (Good), driven by Ozone. AQI flat over the last 6 hours (within ±3 points).
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
Trends
Seven days of AQI and PM2.5.
Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).
September dries up ditches or breaks down bridges.
- Moonrise
- 4:26 PM
- Moonset
- 1:13 AM
- In sign
- ♑︎ Capricorn
Thunder quiets the land
Read this microseason across nine climate regions →
All 72 microseasons on the year wheel →
Champaign at a glance
- Today vs. normal: Today averages 63°F (high 65°F, low 60°F), 2°F below the 65°F normal for Sep 21
- Last frost: April 15 (1991–2020 median, NOAA station 4 km away)
- Microseason: Sep 21–25
- Planting calendar: September — plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, winter squash
16-Day Forecast — Champaign
- Mon66°60°61%
- Tue63°57°5%
- Wed65°56°1%
- Thu68°56°0%
- Fri71°59°0%
- Sat66°58°2%
- Sun77°59°8%
- Mon80°62°11%
- Tue72°66°31%
- Wed75°56°24%
- Thu77°57°9%
- Fri76°57°17%
- Sat84°63°17%
- Sun65°52°13%
- Mon58°43°17%
- Tue61°40°20%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near Champaign
Interactive wind and temperature map centered on Champaign — it loads in your browser. Open the full weather map.
Right now in the garden
Fall planting + final harvests
As of September 21, the season's first frost (typically October 24) is approaching. Pick what frost-tender plants still carry before the next cold front. This city's planting calendar for September: plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, and winter squash.
Sun & seasons in Champaign
Champaign sits in Champaign County, where the year’s longest day runs 15h 2m of daylight and its shortest just 9h 19m — a swing of +5h 43m between the June and December solstices. Clocks spring forward on Sunday, March 8, 2026 and fall back on Sunday, November 1, 2026.
Chicago, the state’s largest city, lies about 123 miles to the NNE. The nearest town Champaign tracks is Rankin, roughly 31 miles to the NE.
Air quality in Champaign
Air quality in Champaign’s county has held roughly steady since 2020; its cleanest year on record was 2025 (median AQI 43). See the full air-quality history for Champaign.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| March | lettuce, peas, spinach, radishes | — |
| April | lettuce, peas, spinach, radishes | radishes |
| May | tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, spinach |
| July | tomatoes, peppers, beans, squash | lettuce, peas, tomatoes, peppers, beans, summer squash, garlic |
| August | beans, squash, fall brassicas, carrots | tomatoes, peppers, beans, summer squash, winter squash |
| September | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash |
| October | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash, fall brassicas, carrots |
| November | — | fall brassicas, carrots |
A year in weather
Champaign's warmest month is July (~75°F mean) and its coldest is January (~26°F). Rainfall peaks in May (4.8 inches) and bottoms out in February (2.2 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 26° | 2.3″ | 5 |
| February | 30° | 2.2″ | 5 |
| March | 41° | 2.8″ | 6 |
| April | 52° | 3.9″ | 8 |
| May | 63° | 4.8″ | 9 |
| June | 72° | 4.6″ | 7 |
| July | 75° | 4.5″ | 7 |
| August | 74° | 3.5″ | 6 |
| September | 67° | 3.4″ | 5 |
| October | 55° | 3.4″ | 6 |
| November | 41° | 3.2″ | 6 |
| December | 31° | 2.4″ | 5 |
Regional context
Similar climates Savoy, IL, Urbana, IL, Bondville, IL
Champaign swings from 26°F in January to 75°F in July (50°F) per NOAA NCEI 1991-2020 normals; precipitation in Champaign runs about 40.9 inches on roughly 74 measurable days.
Summer convection drives Champaign's precipitation: May logs 4.8 inches on 8.6 rainy days, against February's 2.2 inches on 4.6 — warm-season storms carry Champaign's moisture. That summer-storm rhythm groups Champaign with places like Savoy, IL, Urbana, IL and Bondville, IL.
Around April 15, Champaign sheds its freezing nights — kale, peas, spinach, and parsnips go into Champaign's beds. Heat-demanding starts go out a fortnight on in Champaign, after the soil warms and cold snaps clear. Frost returns to Champaign near October 24, ending the tender-crop season. That date is a median: Champaign freezes sooner in half of years.
Similar climates: Savoy, IL, Urbana, IL, Bondville, IL, Mahomet, IL, Seymour, IL.
Frequently asked
- When does it freeze in Champaign?
- Champaign's last spring frost lands near April 15, and in Champaign the first fall frost follows around October 24.
- What is the rainy season in Champaign?
- May is the wettest month in Champaign, about 4.8 inches on average; the year totals roughly 41 inches.
- What is the warmest month in Champaign?
- On average July tops the year in Champaign at about 75°F.
- What is the coldest month in Champaign?
- The coldest stretch in Champaign falls in January, around 26°F on average.
- When can I start a vegetable garden in Champaign?
- In Champaign, sow peas and hardy greens around April 15; Champaign's tomatoes and peppers wait two weeks more.
- How many rainy days does Champaign get?
- Expect roughly 74 wet days a year in Champaign.
- What hardiness zone is Champaign?
- Because Champaign bottoms near 26°F in January, that winter low sets Champaign's USDA zone — verify by ZIP.
- What is the 10-day forecast for Champaign?
- Champaign's extended outlook — daily high and low temperatures and precipitation chances for each upcoming day — is in the daily forecast above.
- Will it rain this week in Champaign?
- See this week's day-by-day rain chances for Champaign in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Champaign?
- Current conditions for Champaign and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Champaign forecast updated?
- The Champaign forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Champaign?
- Today's sunrise and sunset times for Champaign are in the Almanac section above, along with civil dawn, civil dusk, and day length. Day length is longest near the summer solstice and shortest near the winter solstice.
- How accurate is the weather forecast for Champaign?
- The next few days in Champaign's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Champaign sits at 40.1°N; its climate zone is humid subtropical (Köppen approximation).
ZIP codes in Champaign
- 61820
- 61821
- 61822
- 61824
- 61825
- 61826