Fairfield, Illinois Weather
Cicadas claim the scorching afternoon. Day 14 of summer. Read this microseason across nine climate regions →
Fairfield weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Overcast20%—94°69°—
- SundayJul 5Light Drizzle23%0.02″85°72°-9°
- MondayJul 6Light Drizzle25%—87°70°+2°
- TuesdayJul 7Overcast11%—84°68°-3°
- WednesdayJul 8Mostly Clear11%—87°66°+3°
- ThursdayJul 9Light Drizzle34%—89°71°+2°
- FridayJul 10Drizzle39%0.06″84°72°-5°
AQI 47 (Good), driven by Ozone. AQI flat over the last 6 hours (within ±3 points). Ozone at AQI 43 now. With UV 4.9 peaking around 1 PM under partly cloudy skies, surface ozone likely climbs to AQI 20 around 1 PM.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
Ozone × UV × Sky
Ozone at AQI 43 now. With UV 4.9 peaking around 1 PM under partly cloudy skies, surface ozone likely climbs to AQI 20 around 1 PM.
- Present
- AQI 43
- UV peak
- 4.9 at 1 PM
- Sky at peak
- partly cloudy
- Projected peak
- AQI 20
PM × Wind × Precip
PM2.5 at 5.7 µg/m³ (AQI 32) with a 0.95 fine-to-coarse ratio and 5 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.95
- Wind
- light
- Recent rain
- 0h in last 6h
- Pattern
- stagnant smoke
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).
If the first of July be rainy weather, 'twill rain more or less for four weeks together.
- Moonrise
- 10:46 PM
- Moonset
- 10:01 AM
- In sign
- ♓︎ Pisces
Cicadas claim the scorching afternoon
Fairfield at a glance
- Today vs. normal: 12°F above the seasonal normal for this latitude
- Last frost: April 6 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP code: 62837
16-Day Forecast — Fairfield
- Sat94°69°20%
- Sun85°72°23%
- Mon87°70°25%
- Tue84°68°11%
- Wed87°66°11%
- Thu89°71°34%
- Fri84°72°39%
- Sat89°72°32%
- Sun77°62°14%
- Mon74°58°8%
- Tue79°61°12%
- Wed82°63°10%
- Thu83°66°16%
- Fri78°71°19%
- Sat86°70°23%
- Sun87°73°17%
Forecast data from Open-Meteo (CC BY 4.0).
Right now in the garden
Peak growing season
As of July 4, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.
SPC Convective Outlook
Storm Prediction Center — Fairfield
SPC has placed Fairfield in the Slight Risk category for severe thunderstorms today.
- TODAYSLGTSlight Risk
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3TSTMGeneral Thunderstorms
Scattered severe storms possible. A few tornadoes, hail, and damaging wind gusts possible.
Source: NOAA / NWS Storm Prediction Center categorical convective outlook. Outlooks are re-issued multiple times per day; this page reflects the most recent SPC polygons covering the city’s coordinates.
ZIP codes in Fairfield
- 62837