Lake Petersburg, Illinois Weather
Fireflies pulse through the magnolias. Day 76 of spring. Read this microseason across nine climate regions →
Lake Petersburg weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 3Partly Cloudy——81°52°—
- ThursdayJun 4Overcast——84°57°+3°
- FridayJun 5Drizzle41%—83°66°-1°
- SaturdayJun 6Light Showers45%—83°67°0°
- SundayJun 7Showers22%—85°69°+2°
- MondayJun 8Showers42%0.01″80°70°-5°
- TuesdayJun 9Drizzle24%0.04″78°71°-2°
Ozone at AQI 65 now. AQI up 7 over the last 6 hours (gradual rise). With UV 8.9 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 77 by mid-afternoon.
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 65 now. With UV 8.9 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 77 by mid-afternoon.
- Present
- AQI 65
- UV peak
- 8.9 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 77
PM × Wind × Precip
PM2.5 at 6.4 µg/m³ (AQI 36) with a 0.83 fine-to-coarse ratio and 6 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.83
- 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).
The higher the clouds, the finer the weather.
- Moonrise
- 3:51 AM
- Moonset
- 12:59 PM
- In sign
- ♑︎ Capricorn
Fireflies pulse through the magnolias
Lake Petersburg at a glance
- Today vs. normal: 5°F above the seasonal normal for this latitude
- Last frost: April 16 (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 — Lake Petersburg
SPC has placed Lake Petersburg 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.