Current Conditions

O'Fallon, Illinois

65°F18°C

Cloudy

Wind

NNE 8 mph13 km/h

Humidity

74%

Cloud Cover

95%

As of Wednesday, September 23, 2026 at 9:11 AM CDT

Today's Outlook

Day

Overcast and warm, with a high of 69°F21°C and morning low of 61°F16°C. Breezy from the NNE at 8 mph12 km/h.

Night

Overcast, with a low around 65°F18°C. Light wind from the NNE around 7 mph10 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Cloudy	High 69°F21°C	Low 61°F16°C	Precip 0.01 in0.2 mm6%	Cloud 93%	Wind NNE 7 mph12 km/h	Wednesday: Overcast and warm, with a high of 69°F21°C and morning low of 61°F16°C. Breezy from the NNE at 8 mph12 km/h. Wednesday Night: Overcast, with a low around 65°F18°C. Light wind from the NNE around 7 mph10 km/h.
Cloudy	High 72°F22°C	Low 61°F16°C	Precip 0 in0.1 mm2%	Cloud 88%	Wind NE 5 mph8 km/h	Thursday: Overcast and warm, with a high of 72°F22°C and morning low of 61°F16°C. Light wind from the NNE around 5 mph8 km/h. Thursday Night: Overcast, with a low around 62°F17°C. Light wind from the NE around 5 mph7 km/h.
Partly Cloudy	High 76°F24°C	Low 62°F17°C	Precip 0 in0.1 mm3%	Cloud 80%	Wind NE 4 mph7 km/h	Friday: Overcast and warm, with a high of 76°F24°C and morning low of 62°F17°C. Light wind from the ENE around 4 mph7 km/h. Friday Night: Mostly cloudy, with a low around 63°F17°C. Light wind from the NE around 4 mph7 km/h.
Drizzle	High 72°F22°C	Low 60°F16°C	Precip 0.02 in0.6 mm20%	Cloud 88%	Wind ENE 4 mph6 km/h	Saturday: Overcast and warm, with a high of 72°F22°C and morning low of 60°F16°C. Light wind from the ENE around 3 mph6 km/h. 20% chance of drizzle around midday. Dry air. Saturday Night: Overcast, with a low around 62°F17°C. Light wind from the ENE around 4 mph7 km/h. 15% chance of drizzle in the evening.
Drizzle	High 76°F25°C	Low 59°F15°C	Precip 0.02 in0.6 mm17%	Cloud 60%	Wind NE 4 mph6 km/h	Sunday: Mostly cloudy and warm, with a high of 76°F25°C and morning low of 59°F15°C. Light wind from the NE around 4 mph6 km/h. 17% chance of drizzle in the morning. Dry air. Sunday Night: Mostly cloudy, with a low around 61°F16°C. Light wind from the NE around 4 mph7 km/h. 14% chance of drizzle overnight.
Clear	High 80°F27°C	Low 55°F13°C	Precip 0 in0 mm—	Cloud 16%	Wind ENE 4 mph6 km/h	Monday: Mostly clear and warm, with a high of 80°F27°C and morning low of 55°F13°C. Light wind from the ENE around 3 mph6 km/h. Dry air. Monday Night: Mostly clear, with a low around 58°F14°C. Light wind from the ENE around 4 mph7 km/h.
Showers	High 82°F28°C	Low 55°F13°C	Precip 0.05 in1.3 mm25%	Cloud 60%	Wind SSE 6 mph9 km/h	Tuesday: Mostly cloudy and warm, with a high of 82°F28°C and morning low of 55°F13°C. Breezy from the SSE at 6 to 7 mph10 to 12 km/h. Dry air. Tuesday Night: Mostly cloudy, with a low around 58°F14°C. Breezy from the SSE at 6 to 7 mph9 to 12 km/h. 25% chance of showers in the evening.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 23	69°F21°C	61°F16°C	0.01 in0.2 mm· 6%	93%	Cloudy	NNE 7 mph12 km/h
DayOvercast and warm, with a high of 69°F21°C and morning low of 61°F16°C. Breezy from the NNE at 8 mph12 km/h. NightOvercast, with a low around 65°F18°C. Light wind from the NNE around 7 mph10 km/h.
	ThursdaySep 24	72°F22°C	61°F16°C	0 in0.1 mm· 2%	88%	Cloudy	NE 5 mph8 km/h
DayOvercast and warm, with a high of 72°F22°C and morning low of 61°F16°C. Light wind from the NNE around 5 mph8 km/h. NightOvercast, with a low around 62°F17°C. Light wind from the NE around 5 mph7 km/h.
	FridaySep 25	76°F24°C	62°F17°C	0 in0.1 mm· 3%	80%	Partly Cloudy	NE 4 mph7 km/h
DayOvercast and warm, with a high of 76°F24°C and morning low of 62°F17°C. Light wind from the ENE around 4 mph7 km/h. NightMostly cloudy, with a low around 63°F17°C. Light wind from the NE around 4 mph7 km/h.
	SaturdaySep 26	72°F22°C	60°F16°C	0.02 in0.6 mm· 20%	88%	Drizzle	ENE 4 mph6 km/h
DayOvercast and warm, with a high of 72°F22°C and morning low of 60°F16°C. Light wind from the ENE around 3 mph6 km/h. 20% chance of drizzle around midday. Dry air. NightOvercast, with a low around 62°F17°C. Light wind from the ENE around 4 mph7 km/h. 15% chance of drizzle in the evening.
	SundaySep 27	76°F25°C	59°F15°C	0.02 in0.6 mm· 17%	60%	Drizzle	NE 4 mph6 km/h
DayMostly cloudy and warm, with a high of 76°F25°C and morning low of 59°F15°C. Light wind from the NE around 4 mph6 km/h. 17% chance of drizzle in the morning. Dry air. NightMostly cloudy, with a low around 61°F16°C. Light wind from the NE around 4 mph7 km/h. 14% chance of drizzle overnight.
	MondaySep 28	80°F27°C	55°F13°C	0 in0 mm· —	16%	Clear	ENE 4 mph6 km/h
DayMostly clear and warm, with a high of 80°F27°C and morning low of 55°F13°C. Light wind from the ENE around 3 mph6 km/h. Dry air. NightMostly clear, with a low around 58°F14°C. Light wind from the ENE around 4 mph7 km/h.
	TuesdaySep 29	82°F28°C	55°F13°C	0.05 in1.3 mm· 25%	60%	Showers	SSE 6 mph9 km/h
DayMostly cloudy and warm, with a high of 82°F28°C and morning low of 55°F13°C. Breezy from the SSE at 6 to 7 mph10 to 12 km/h. Dry air. NightMostly cloudy, with a low around 58°F14°C. Breezy from the SSE at 6 to 7 mph9 to 12 km/h. 25% chance of showers in the evening.
	WednesdaySep 30	76°F24°C	64°F18°C	0.36 in9.1 mm· 35%	83%	Light Rain	SSW 7 mph12 km/h
DayOvercast and warm, with a high of 76°F24°C and morning low of 64°F18°C. Breezy from the SW at 8 to 9 mph13 to 14 km/h. 35% chance of light rain throughout the day. NightOvercast, with a low around 66°F19°C. Breezy from the S at 7 mph11 km/h. 33% chance of light rain throughout the night.
	ThursdayOct 1	75°F24°C	61°F16°C	0.31 in7.8 mm· 35%	65%	Showers	WSW 7 mph12 km/h
DayMostly cloudy and warm, with a high of 75°F24°C and morning low of 61°F16°C. Breezy from the WSW at 8 to 9 mph13 to 14 km/h. 35% chance of showers throughout the day. NightMostly cloudy, with a low around 63°F17°C. Breezy from the SSW at 7 mph11 km/h. 33% chance of showers throughout the night.
	FridayOct 2	76°F24°C	59°F15°C	0.19 in4.9 mm· 25%	54%	Showers	SSW 7 mph12 km/h
DayMostly cloudy and warm, with a high of 76°F24°C and morning low of 59°F15°C. Breezy from the SW at 8 to 9 mph13 to 14 km/h. 25% chance of showers throughout the day. NightMostly cloudy, with a low around 61°F16°C. Breezy from the S at 7 mph11 km/h. 23% chance of showers throughout the night.
	SaturdayOct 3	76°F25°C	59°F15°C	0.08 in2.1 mm· 12%	49%	Drizzle	WSW 7 mph11 km/h
DayMostly cloudy and warm, with a high of 76°F25°C and morning low of 59°F15°C. Breezy from the WSW at 7 to 8 mph12 to 13 km/h. 12% chance of drizzle throughout the day. NightPartly cloudy, with a low around 61°F16°C. Breezy from the WSW at 7 mph11 km/h. 11% chance of drizzle throughout the night.
	SundayOct 4	74°F24°C	58°F14°C	0.1 in2.6 mm· 14%	45%	Showers	WNW 7 mph12 km/h
DayPartly cloudy and warm, with a high of 74°F24°C and morning low of 58°F14°C. Breezy from the WNW at 8 to 9 mph12 to 14 km/h. 14% chance of drizzle throughout the day. NightPartly cloudy, with a low around 60°F16°C. Breezy from the WNW at 7 mph11 km/h. 13% chance of showers throughout the night.
	MondayOct 5	73°F23°C	55°F13°C	0.12 in3 mm· 13%	42%	Showers	W 7 mph11 km/h
DayPartly cloudy and warm, with a high of 73°F23°C and morning low of 55°F13°C. Breezy from the W at 7 to 8 mph12 to 13 km/h. 11% chance of drizzle throughout the day. Dry air. NightPartly cloudy, with a low around 57°F14°C. Breezy from the W at 7 mph11 km/h. 13% chance of showers throughout the night.
	TuesdayOct 6	73°F23°C	54°F12°C	0.11 in2.7 mm· 11%	41%	Showers	W 7 mph12 km/h
DayPartly cloudy and warm, with a high of 73°F23°C and morning low of 54°F12°C. Breezy from the W at 8 to 9 mph12 to 14 km/h. 10% chance of showers throughout the day. Dry air. NightPartly cloudy, with a low around 56°F13°C. Breezy from the W at 7 mph11 km/h. 11% chance of drizzle throughout the night.
	WednesdayOct 7	72°F22°C	53°F11°C	0.04 in0.9 mm· 10%	37%	Drizzle	WNW 7 mph12 km/h
DayPartly cloudy and warm, with a high of 72°F22°C and morning low of 53°F11°C. Breezy from the NW at 8 to 9 mph12 to 14 km/h. Dry air. NightPartly cloudy, with a low around 55°F13°C. Breezy from the WNW at 7 mph11 km/h. 10% chance of drizzle overnight.

Nearby Cities

Fairview Heights4 mi7 km Belleville6 mi10 km Collinsville7 mi11 km East Saint Louis13 mi21 km Granite City15 mi24 km Edwardsville15 mi25 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: 38.5923°N, 89.9112°W·Elevation: 167m·Timezone: America/Chicago·Population: 29,002