Vandalia, Illinois Weather
Cicadas claim the scorching afternoon. Day 15 of summer. Read this microseason across nine climate regions →
Vandalia weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 5Overcast12%—88°70°—
- MondayJul 6Overcast10%—85°69°-3°
- TuesdayJul 7Overcast——84°68°-1°
- WednesdayJul 8Overcast——86°65°+2°
- ThursdayJul 9Showers40%—90°72°+4°
- FridayJul 10Drizzle46%—85°72°-5°
- SaturdayJul 11Drizzle35%—83°69°-2°
AQI 40 (Good), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 9.5 µg/m³ (AQI 52) with a 0.87 fine-to-coarse ratio and 2 mph wind — combustion smoke trapped in calm air, not road dust.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion during the projected peak around 10 PM.
What's driving it
Ozone × UV × Sky
Ozone at AQI 50. Overcast through the UV peak window (cloud cover ~100%) — afternoon ozone should stay flat.
- Present
- AQI 50
- UV peak
- 5.7 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 19
PM × Wind × Precip
PM2.5 at 9.5 µg/m³ (AQI 52) with a 0.87 fine-to-coarse ratio and 2 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.87
- Wind
- calm
- 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
- 11:13 PM
- Moonset
- 11:09 AM
- In sign
- ♓︎ Pisces
Cicadas claim the scorching afternoon
Vandalia at a glance
- Today vs. normal: 6°F above the seasonal normal for this latitude
- Last frost: April 10 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP code: 62471
16-Day Forecast — Vandalia
- Sun88°70°12%
- Mon85°69°10%
- Tue84°68°4%
- Wed86°65°6%
- Thu90°72°40%
- Fri85°72°46%
- Sat83°69°35%
- Sun88°70°15%
- Mon91°71°15%
- Tue94°75°6%
- Wed82°65°10%
- Thu80°57°19%
- Fri84°63°26%
- Sat92°67°33%
- Sun90°72°29%
- Mon91°74°19%
Forecast data from Open-Meteo (CC BY 4.0).
Right now in the garden
Peak growing season
As of July 5, 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 — Vandalia
SPC includes Vandalia in the general thunderstorm area today — no severe risk, but storms are possible.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3NONENo severe risk
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.
ZIP codes in Vandalia
- 62471