Colchester, Illinois Weather
Cicadas claim the scorching afternoon. Day 15 of summer. Read this microseason across nine climate regions →
Colchester weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 5Overcast——87°70°—
- MondayJul 6Overcast——87°68°0°
- TuesdayJul 7Overcast——83°63°-4°
- WednesdayJul 8Overcast——86°65°+3°
- ThursdayJul 9Showers35%0.11″87°68°+1°
- FridayJul 10Drizzle47%0.03″80°69°-7°
- SaturdayJul 11Light Showers22%0.16″84°67°+4°
AQI 25 (Good), driven by Ozone. Ozone at AQI 44 now. With UV 6.1 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 36 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 44 now. With UV 6.1 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 36 around 1 PM.
- Present
- AQI 44
- UV peak
- 6.1 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 36
PM × Wind × Precip
PM2.5 at 6.1 µg/m³ (AQI 34) with a 0.82 fine-to-coarse ratio and 6 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.82
- 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
- 11:22 PM
- Moonset
- 11:15 AM
- In sign
- ♓︎ Pisces
Cicadas claim the scorching afternoon
Colchester at a glance
- Today vs. normal: 12°F above the seasonal normal for this latitude
- Last frost: April 19 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP code: 62326
16-Day Forecast — Colchester
- Sun87°70°9%
- Mon87°68°3%
- Tue83°63°0%
- Wed86°65°3%
- Thu87°68°35%
- Fri80°69°47%
- Sat84°67°22%
- Sun87°69°10%
- Mon92°71°5%
- Tue92°76°3%
- Wed77°63°7%
- Thu78°57°20%
- Fri84°64°26%
- Sat87°68°24%
- Sun88°73°23%
- Mon90°73°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 — Colchester
SPC includes Colchester in the general thunderstorm area today — no severe risk, but storms are possible.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWNONENo severe risk
- 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 Colchester
- 62326