Alton, Indiana Weather
Cicadas claim the scorching afternoon. Day 14 of summer. Read this microseason across nine climate regions →
Alton weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Overcast14%—89°70°—
- SundayJul 5Overcast27%—86°73°-3°
- MondayJul 6Light Drizzle31%—89°72°+3°
- TuesdayJul 7Overcast12%—85°68°-4°
- WednesdayJul 8Clear15%—90°66°+5°
- ThursdayJul 9Thunderstorm26%—91°67°+1°
- FridayJul 10Showers50%0.74″78°69°-13°
AQI 47 (Good), driven by Ozone. AQI down 5 over the last 6 hours (gradual decline). Ozone at AQI 60 now. With UV 7.4 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 59 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 60 now. With UV 7.4 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 59 around 1 PM.
- Present
- AQI 60
- UV peak
- 7.4 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 59
PM × Wind × Precip
PM2.5 at 11.4 µg/m³ (AQI 55) with a 0.86 fine-to-coarse ratio and 4 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.86
- 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
- 11:38 PM
- Moonset
- 10:53 AM
- In sign
- ♓︎ Pisces
Cicadas claim the scorching afternoon
Alton at a glance
- Today vs. normal: 11°F above the seasonal normal for this latitude
- Last frost: April 5 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
16-Day Forecast — Alton
- Sat89°70°14%
- Sun86°73°27%
- Mon89°72°31%
- Tue85°68°12%
- Wed90°66°15%
- Thu91°67°26%
- Fri78°69°50%
- Sat87°71°39%
- Sun81°66°18%
- Mon77°59°9%
- Tue80°60°12%
- Wed85°63°13%
- Thu87°66°19%
- Fri87°71°19%
- Sat85°71°26%
- Sun89°72°39%
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 — Alton
SPC includes Alton in the general thunderstorm area today — no severe risk, but storms are possible.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWTSTMGeneral Thunderstorms
- 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.
ZIP codes in Alton
- 47137