Flat Rock, Illinois Weather
Fireflies pulse through the magnolias. Day 76 of spring. Read this microseason across nine climate regions →
Flat Rock weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 3Overcast——82°55°—
- ThursdayJun 4Overcast——85°60°+3°
- FridayJun 5Overcast——80°62°-5°
- SaturdayJun 6Showers19%0.17″84°64°+4°
- SundayJun 7Light Showers29%—87°68°+3°
- MondayJun 8Light Showers29%—76°69°-11°
- TuesdayJun 9Drizzle21%—75°69°-1°
Ozone at AQI 88 — peak already passed at 1 PM under overcast skies. AQI up 18 in the last 6 hours — air quality is degrading. Levels should ease through evening.
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 88 — peak already passed at 1 PM under overcast skies. Levels should ease through evening.
- Present
- AQI 88
- UV peak
- 5.9 at earlier today
- Sky at peak
- overcast
- Projected peak
- AQI 88
PM × Wind × Precip
PM2.5 at 5.6 µg/m³, PM10 at 6.4 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.87
- Wind
- breezy
- Recent rain
- 0h in last 6h
- Pattern
- background
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).
The higher the clouds, the finer the weather.
- Moonrise
- 3:38 AM
- Moonset
- 12:53 PM
- In sign
- ♑︎ Capricorn
Fireflies pulse through the magnolias
Flat Rock at a glance
- Today vs. normal: 6°F above the seasonal normal for this latitude
- Last frost: April 9 (climatological average for this latitude)
- Microseason: Jun 1–5
- Planting window: Harvest spring lettuce before it bolts. Sow heat-tolerant greens.
Right now in the garden
Peak growing season
As of June 3, 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 — Flat Rock
SPC has placed Flat Rock in the General Thunderstorms category for severe thunderstorms day after tomorrow.
- TODAYNONENo severe risk
- TOMORROWNONENo severe risk
- DAY 3TSTMGeneral Thunderstorms
Thunderstorms possible. Not severe, but capable of producing lightning and brief heavy rain.
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.