Current Conditions

Alton, Illinois

83°F28°C

Drizzle

Wind

SSE 7 mph12 km/h

Humidity

49%

Cloud Cover

45%

As of Tuesday, September 8, 2026 at 10:45 PM CDT

Today's Outlook

Night

Partly cloudy, with a low around 77°F25°C. Breezy from the S at 6 to 8 mph9 to 12 km/h. 31% chance of drizzle in the evening.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Drizzle	High 93°F34°CFeels 98°F37°C	Low 76°F25°C	Precip 0.03 in0.8 mm31%	Cloud 41%	Wind SW 5 mph9 km/h	Wednesday: Partly cloudy and hot, with a high of 93°F34°C and morning low of 76°F25°C — feels like 99°F37°C. Breezy from the WSW at 5 to 7 mph8 to 12 km/h. Heat risk in the afternoon. Wednesday Night: Partly cloudy, with a low around 77°F25°C. Breezy from the S at 6 to 8 mph9 to 12 km/h. 31% chance of drizzle in the evening.
Rain	High 78°F26°C	Low 72°F22°C	Precip 0.72 in18.3 mm95%	Cloud 92%	Wind NNW 4 mph6 km/h	Thursday: Overcast and warm, with a high of 78°F26°C and morning low of 73°F23°C. Light wind from the WNW around 4 mph7 km/h. 95% chance of rain throughout the day. Heavy, humid air. Thursday Night: Overcast, with a low around 72°F22°C. Light wind from the NNE around 4 mph6 km/h. 90% chance of rain throughout the night.
Showers	High 84°F29°C	Low 69°F20°C	Precip 0.13 in3.4 mm32%	Cloud 56%	Wind E 4 mph6 km/h	Friday: Mostly cloudy and warm, with a high of 84°F29°C and morning low of 69°F20°C. Light wind from the ESE around 4 mph6 km/h. 32% chance of showers throughout the day. Humid. Friday Night: Partly cloudy, with a low around 69°F21°C. Light wind from the E around 4 mph6 km/h. 14% chance of drizzle throughout the night.
Drizzle	High 88°F31°CFeels 92°F33°C	Low 69°F21°C	Precip 0.04 in0.9 mm11%	Cloud 46%	Wind SSW 5 mph7 km/h	Saturday: Mostly cloudy and hot, with a high of 88°F31°C and morning low of 69°F21°C. Light wind from the SW around 5 mph8 km/h. 11% chance of drizzle around midday. Humid. Saturday Night: Partly cloudy, with a low around 70°F21°C. Light wind from the S around 4 mph7 km/h.
Clear	High 88°F31°C	Low 69°F21°C	Precip 0.03 in0.7 mm8%	Cloud 33%	Wind NNE 5 mph8 km/h	Sunday: Partly cloudy and hot, with a high of 88°F31°C and morning low of 69°F21°C. Light wind from the N around 5 mph8 km/h. Humid. Sunday Night: Mostly clear, with a low around 71°F22°C. Light wind from the NE around 5 mph8 km/h.
Clear	High 93°F34°C	Low 70°F21°C	Precip 0.02 in0.5 mm6%	Cloud 24%	Wind SSE 8 mph14 km/h	Monday: Partly cloudy and hot, with a high of 93°F34°C and morning low of 70°F21°C. Breezy from the SSE at 9 to 10 mph14 to 17 km/h. Monday Night: Mostly clear, with a low around 72°F22°C. Breezy from the SSE at 8 to 11 mph13 to 17 km/h.
Drizzle	High 92°F33°CFeels 95°F35°C	Low 75°F24°C	Precip 0.06 in1.5 mm19%	Cloud 37%	Wind SSW 8 mph13 km/h	Tuesday: Partly cloudy and hot, with a high of 92°F33°C and morning low of 75°F24°C. Breezy from the SW at 8 mph13 km/h. 11% chance of drizzle around midday. Humid. Tuesday Night: Partly cloudy, with a low around 77°F25°C. Breezy from the S at 8 to 10 mph13 to 16 km/h. 19% chance of drizzle throughout the night.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 9	93°F34°C Feels 98°F37°C	76°F25°C	0.03 in0.8 mm· 31%	41%	Drizzle	SW 5 mph9 km/h
DayPartly cloudy and hot, with a high of 93°F34°C and morning low of 76°F25°C — feels like 99°F37°C. Breezy from the WSW at 5 to 7 mph8 to 12 km/h. Heat risk in the afternoon. NightPartly cloudy, with a low around 77°F25°C. Breezy from the S at 6 to 8 mph9 to 12 km/h. 31% chance of drizzle in the evening.
	ThursdaySep 10	78°F26°C	72°F22°C	0.72 in18.3 mm· 95%	92%	Rain	NNW 4 mph6 km/h
DayOvercast and warm, with a high of 78°F26°C and morning low of 73°F23°C. Light wind from the WNW around 4 mph7 km/h. 95% chance of rain throughout the day. Heavy, humid air. NightOvercast, with a low around 72°F22°C. Light wind from the NNE around 4 mph6 km/h. 90% chance of rain throughout the night.
	FridaySep 11	84°F29°C	69°F20°C	0.13 in3.4 mm· 32%	56%	Showers	E 4 mph6 km/h
DayMostly cloudy and warm, with a high of 84°F29°C and morning low of 69°F20°C. Light wind from the ESE around 4 mph6 km/h. 32% chance of showers throughout the day. Humid. NightPartly cloudy, with a low around 69°F21°C. Light wind from the E around 4 mph6 km/h. 14% chance of drizzle throughout the night.
	SaturdaySep 12	88°F31°C Feels 92°F33°C	69°F21°C	0.04 in0.9 mm· 11%	46%	Drizzle	SSW 5 mph7 km/h
DayMostly cloudy and hot, with a high of 88°F31°C and morning low of 69°F21°C. Light wind from the SW around 5 mph8 km/h. 11% chance of drizzle around midday. Humid. NightPartly cloudy, with a low around 70°F21°C. Light wind from the S around 4 mph7 km/h.
	SundaySep 13	88°F31°C	69°F21°C	0.03 in0.7 mm· 8%	33%	Clear	NNE 5 mph8 km/h
DayPartly cloudy and hot, with a high of 88°F31°C and morning low of 69°F21°C. Light wind from the N around 5 mph8 km/h. Humid. NightMostly clear, with a low around 71°F22°C. Light wind from the NE around 5 mph8 km/h.
	MondaySep 14	93°F34°C	70°F21°C	0.02 in0.5 mm· 6%	24%	Clear	SSE 8 mph14 km/h
DayPartly cloudy and hot, with a high of 93°F34°C and morning low of 70°F21°C. Breezy from the SSE at 9 to 10 mph14 to 17 km/h. NightMostly clear, with a low around 72°F22°C. Breezy from the SSE at 8 to 11 mph13 to 17 km/h.
	TuesdaySep 15	92°F33°C Feels 95°F35°C	75°F24°C	0.06 in1.5 mm· 19%	37%	Drizzle	SSW 8 mph13 km/h
DayPartly cloudy and hot, with a high of 92°F33°C and morning low of 75°F24°C. Breezy from the SW at 8 mph13 km/h. 11% chance of drizzle around midday. Humid. NightPartly cloudy, with a low around 77°F25°C. Breezy from the S at 8 to 10 mph13 to 16 km/h. 19% chance of drizzle throughout the night.
	WednesdaySep 16	88°F31°C Feels 91°F33°C	72°F22°C	0.13 in3.4 mm· 28%	54%	Showers	SE 6 mph10 km/h
DayMostly cloudy and hot, with a high of 88°F31°C and morning low of 72°F22°C. Light wind from the SSE around 6 mph9 km/h. 28% chance of showers throughout the day. Humid. NightMostly cloudy, with a low around 74°F23°C. Breezy from the ESE at 6 to 7 mph10 to 12 km/h. 26% chance of showers throughout the night.
	ThursdaySep 17	89°F32°C	73°F23°C	0.17 in4.2 mm· 22%	44%	Showers	SSW 7 mph12 km/h
DayPartly cloudy and hot, with a high of 89°F32°C and morning low of 73°F23°C. Breezy from the SSW at 8 mph12 km/h. 19% chance of showers throughout the day. Humid. NightPartly cloudy, with a low around 74°F23°C. Breezy from the S at 7 to 8 mph12 to 12 km/h. 22% chance of showers throughout the night.
	FridaySep 18	80°F27°C	68°F20°C	0.16 in4 mm· 23%	51%	Showers	NW 7 mph12 km/h
DayMostly cloudy and warm, with a high of 80°F27°C and morning low of 68°F20°C. Breezy from the NW at 8 mph12 km/h. 19% chance of showers throughout the day. NightPartly cloudy, with a low around 69°F20°C. Breezy from the NW at 7 to 8 mph11 to 12 km/h. 23% chance of showers throughout the night.
	SaturdaySep 19	78°F25°C	61°F16°C	0.1 in2.5 mm· 16%	47%	Drizzle	N 6 mph10 km/h
DayPartly cloudy and warm, with a high of 78°F25°C and morning low of 61°F16°C. Breezy from the NNW at 6 to 7 mph10 to 11 km/h. 16% chance of drizzle throughout the day. NightPartly cloudy, with a low around 64°F18°C. Light wind from the N around 6 mph10 km/h. 14% chance of drizzle throughout the night.
	SundaySep 20	75°F24°C	59°F15°C	0.16 in4 mm· 17%	52%	Showers	NNE 7 mph11 km/h
DayMostly cloudy and warm, with a high of 75°F24°C and morning low of 59°F15°C. Breezy from the NNE at 7 to 8 mph11 to 12 km/h. 17% chance of showers throughout the day. NightMostly cloudy, with a low around 62°F16°C. Breezy from the NNE at 6 to 7 mph10 to 11 km/h. 16% chance of showers throughout the night.
	MondaySep 21	74°F23°C	57°F14°C	0.11 in2.9 mm· 14%	54%	Showers	NE 7 mph11 km/h
DayMostly cloudy and warm, with a high of 74°F23°C and morning low of 57°F14°C. Breezy from the NE at 7 mph11 km/h. 14% chance of drizzle throughout the day. NightMostly cloudy, with a low around 59°F15°C. Breezy from the NE at 6 to 7 mph10 to 11 km/h. 13% chance of showers throughout the night.
	TuesdaySep 22	74°F24°C	57°F14°C	0.15 in3.9 mm· 18%	53%	Showers	E 6 mph10 km/h
DayMostly cloudy and warm, with a high of 74°F24°C and morning low of 57°F14°C. Breezy from the E at 6 to 7 mph10 to 11 km/h. 18% chance of showers throughout the day. NightMostly cloudy, with a low around 59°F15°C. Breezy from the E at 6 to 7 mph10 to 11 km/h. 15% chance of showers throughout the night.
	WednesdaySep 23	76°F25°C	59°F15°C	0.1 in2.6 mm· 16%	59%	Drizzle	SE 6 mph10 km/h
DayMostly cloudy and warm, with a high of 76°F25°C and morning low of 59°F15°C. Breezy from the SSE at 7 to 8 mph11 to 12 km/h. 16% chance of drizzle throughout the day. NightMostly cloudy, with a low around 60°F16°C. Light wind from the ESE around 6 mph10 km/h. 14% chance of drizzle throughout the night.

Nearby Cities

Upper Alton2 mi4 km Godfrey4 mi7 km Old Jamestown7 mi11 km Spanish Lake7 mi12 km Florissant10 mi16 km Ferguson12 mi19 km

About This Forecast

This forecast is powered by WeatherMesh, the world's most advanced and accurate weather model powered by AI. WeatherMesh is built on proprietary data from WindBorne's Global Sounding Balloon constellation — the world's largest fleet of autonomous, long-duration weather balloons — collecting observations across 100% of Earth, including over oceans and remote regions where no other data exists.

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Coordinates: 38.8906°N, 90.1843°W·Elevation: 150m·Timezone: America/Chicago·Population: 27,003