Current Conditions

O'Fallon, Illinois

82°F28°C

Clear

Wind

SW 7 mph11 km/h

Humidity

53%

Cloud Cover

As of Tuesday, October 13, 2026 at 11:19 AM CDT

Today's Outlook

Day

Mostly clear and hot, with a high of 89°F32°C and morning low of 68°F20°C. Breezy from the SW at 7 mph11 km/h.

Night

Mostly clear, with a low around 68°F20°C. Breezy from the SSW at 8 to 9 mph13 to 15 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Clear	High 89°F32°CFeels 93°F34°C	Low 68°F20°C	Precip 0 in0 mm—	Cloud 11%	Wind SW 8 mph12 km/h	Tuesday: Mostly clear and hot, with a high of 89°F32°C and morning low of 68°F20°C. Breezy from the SW at 7 mph11 km/h. Tuesday Night: Mostly clear, with a low around 68°F20°C. Breezy from the SSW at 8 to 9 mph13 to 15 km/h.
Rain	High 80°F26°C	Low 69°F20°C	Precip 0.42 in10.6 mm89%	Cloud 84%	Wind W 6 mph9 km/h	Wednesday: Overcast and warm, with a high of 73°F23°C. Light wind from the NW around 5 mph8 km/h. 89% chance of rain in the morning. Heavy, humid air. Wednesday Night: Mostly cloudy, with a low around 69°F20°C. Breezy from the WSW at 7 to 9 mph11 to 14 km/h. 40% chance of light rain in the evening.
Light Rain	High 76°F24°C	Low 66°F19°C	Precip 0.38 in9.7 mm70%	Cloud 76%	Wind SSW 8 mph13 km/h	Thursday: Overcast and warm, with a high of 76°F24°C and morning low of 66°F19°C. Breezy from the S at 8 to 9 mph12 to 15 km/h. 70% chance of light rain in the morning. Heavy, humid air. Thursday Night: Mostly cloudy, with a low around 66°F19°C. Breezy from the W at 8 to 13 mph13 to 20 km/h. 61% chance of showers overnight.
Light Rain	High 63°F17°C	Low 48°F9°CFeels 44°F6°C	Precip 0.11 in2.7 mm60%	Cloud 79%	Wind NW 14 mph23 km/h	Friday: Overcast and mild, with a high of 54°F12°C. Windy from the NW at 15 to 17 mph25 to 27 km/h. 28% chance of drizzle in the morning. Dry air. Friday Night: Mostly cloudy, with a low around 48°F9°C. Breezy from the NW at 13 to 15 mph21 to 24 km/h. 60% chance of light rain overnight.
Clear	High 55°F13°C	Low 39°F4°CFeels 34°F1°C	Precip 0.01 in0.2 mm3%	Cloud 9%	Wind N 7 mph11 km/h	Saturday: Mostly clear and mild, with a high of 55°F13°C and morning low of 39°F4°C. Breezy from the N at 6 to 7 mph9 to 12 km/h. Dry air. Saturday Night: Mostly clear, with a low around 40°F4°C. Breezy from the N at 8 to 11 mph12 to 17 km/h.
Clear	High 61°F16°C	Low 38°F3°CFeels 33°F0°C	Precip 0 in0 mm—	Cloud 6%	Wind SSE 7 mph12 km/h	Sunday: Mostly clear and mild, with a high of 61°F16°C and morning low of 38°F3°C. Breezy from the SSE at 7 to 8 mph12 to 12 km/h. Dry air. Sunday Night: Mostly clear, with a low around 38°F3°C. Breezy from the SE at 7 mph12 km/h.
Clear	High 67°F19°C	Low 44°F7°CFeels 40°F5°C	Precip 0 in0 mm—	Cloud 32%	Wind SSE 7 mph11 km/h	Monday: Partly cloudy and mild, with a high of 67°F19°C and morning low of 44°F7°C. Breezy from the S at 7 mph11 km/h. Dry air. Monday Night: Partly cloudy, with a low around 44°F7°C. Breezy from the SSE at 7 to 8 mph11 to 12 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	TuesdayOct 13	89°F32°C Feels 93°F34°C	68°F20°C	0 in0 mm· —	11%	Clear	SW 8 mph12 km/h
DayMostly clear and hot, with a high of 89°F32°C and morning low of 68°F20°C. Breezy from the SW at 7 mph11 km/h. NightMostly clear, with a low around 68°F20°C. Breezy from the SSW at 8 to 9 mph13 to 15 km/h.
	WednesdayOct 14	80°F26°C	69°F20°C	0.42 in10.6 mm· 89%	84%	Rain	W 6 mph9 km/h
DayOvercast and warm, with a high of 73°F23°C. Light wind from the NW around 5 mph8 km/h. 89% chance of rain in the morning. Heavy, humid air. NightMostly cloudy, with a low around 69°F20°C. Breezy from the WSW at 7 to 9 mph11 to 14 km/h. 40% chance of light rain in the evening.
	ThursdayOct 15	76°F24°C	66°F19°C	0.38 in9.7 mm· 70%	76%	Light Rain	SSW 8 mph13 km/h
DayOvercast and warm, with a high of 76°F24°C and morning low of 66°F19°C. Breezy from the S at 8 to 9 mph12 to 15 km/h. 70% chance of light rain in the morning. Heavy, humid air. NightMostly cloudy, with a low around 66°F19°C. Breezy from the W at 8 to 13 mph13 to 20 km/h. 61% chance of showers overnight.
	FridayOct 16	63°F17°C	48°F9°C Feels 44°F6°C	0.11 in2.7 mm· 60%	79%	Light Rain	NW 14 mph23 km/h
DayOvercast and mild, with a high of 54°F12°C. Windy from the NW at 15 to 17 mph25 to 27 km/h. 28% chance of drizzle in the morning. Dry air. NightMostly cloudy, with a low around 48°F9°C. Breezy from the NW at 13 to 15 mph21 to 24 km/h. 60% chance of light rain overnight.
	SaturdayOct 17	55°F13°C	39°F4°C Feels 34°F1°C	0.01 in0.2 mm· 3%	9%	Clear	N 7 mph11 km/h
DayMostly clear and mild, with a high of 55°F13°C and morning low of 39°F4°C. Breezy from the N at 6 to 7 mph9 to 12 km/h. Dry air. NightMostly clear, with a low around 40°F4°C. Breezy from the N at 8 to 11 mph12 to 17 km/h.
	SundayOct 18	61°F16°C	38°F3°C Feels 33°F0°C	0 in0 mm· —	6%	Clear	SSE 7 mph12 km/h
DayMostly clear and mild, with a high of 61°F16°C and morning low of 38°F3°C. Breezy from the SSE at 7 to 8 mph12 to 12 km/h. Dry air. NightMostly clear, with a low around 38°F3°C. Breezy from the SE at 7 mph12 km/h.
	MondayOct 19	67°F19°C	44°F7°C Feels 40°F5°C	0 in0 mm· —	32%	Clear	SSE 7 mph11 km/h
DayPartly cloudy and mild, with a high of 67°F19°C and morning low of 44°F7°C. Breezy from the S at 7 mph11 km/h. Dry air. NightPartly cloudy, with a low around 44°F7°C. Breezy from the SSE at 7 to 8 mph11 to 12 km/h.
	TuesdayOct 20	71°F22°C	49°F10°C	0.01 in0.2 mm· 4%	33%	Clear	SSE 6 mph10 km/h
DayPartly cloudy and warm, with a high of 71°F22°C and morning low of 49°F10°C. Light wind from the SSE around 6 mph10 km/h. Dry air. NightPartly cloudy, with a low around 49°F10°C. Breezy from the SSE at 6 to 7 mph10 to 11 km/h.
	WednesdayOct 21	73°F23°C	54°F12°C	0.05 in1.3 mm· 9%	34%	Clear	SSE 7 mph11 km/h
DayPartly cloudy and warm, with a high of 73°F23°C and morning low of 54°F12°C. Breezy from the SSE at 7 to 8 mph11 to 12 km/h. NightPartly cloudy, with a low around 55°F13°C. Breezy from the SSE at 7 mph11 km/h.
	ThursdayOct 22	73°F23°C	58°F14°C	0.09 in2.4 mm· 16%	60%	Drizzle	S 7 mph12 km/h
DayMostly cloudy and warm, with a high of 73°F23°C and morning low of 58°F14°C. Breezy from the S at 7 to 8 mph12 to 12 km/h. 16% chance of drizzle in the morning. NightMostly cloudy, with a low around 58°F14°C. Breezy from the SSE at 7 to 8 mph12 to 13 km/h. 13% chance of drizzle overnight.
	FridayOct 23	71°F22°C	59°F15°C	0.15 in3.7 mm· 29%	70%	Showers	S 8 mph13 km/h
DayMostly cloudy and warm, with a high of 71°F22°C and morning low of 59°F15°C. Breezy from the S at 8 mph13 km/h. 21% chance of drizzle in the morning. NightMostly cloudy, with a low around 59°F15°C. Breezy from the SSE at 8 mph13 km/h. 29% chance of light rain overnight.
	SaturdayOct 24	68°F20°C	58°F14°C	0.24 in6.2 mm· 32%	70%	Light Rain	SSW 8 mph12 km/h
DayMostly cloudy and warm, with a high of 68°F20°C and morning low of 58°F14°C. Breezy from the SW at 8 mph12 km/h. 32% chance of light rain in the morning. NightMostly cloudy, with a low around 58°F15°C. Breezy from the SSW at 8 mph12 km/h. 30% chance of showers overnight.
	SundayOct 25	64°F18°C	53°F12°C	0.1 in2.6 mm· 18%	61%	Drizzle	W 7 mph12 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 53°F12°C. Breezy from the W at 7 to 8 mph12 to 12 km/h. 17% chance of drizzle in the morning. Dry air. NightMostly cloudy, with a low around 54°F12°C. Breezy from the WSW at 7 to 8 mph12 to 13 km/h. 18% chance of drizzle overnight.
	MondayOct 26	61°F16°C	50°F10°C Feels 47°F8°C	0.14 in3.5 mm· 16%	56%	Showers	WNW 7 mph10 km/h
DayMostly cloudy and mild, with a high of 61°F16°C and morning low of 50°F10°C. Breezy from the WNW at 7 mph11 km/h. 16% chance of showers in the morning. Dry air. NightMostly cloudy, with a low around 50°F10°C. Breezy from the WNW at 6 to 7 mph10 to 12 km/h. 16% chance of drizzle overnight.
	TuesdayOct 27	60°F16°C	48°F9°C	0.09 in2.2 mm· 13%	58%	Drizzle	W 7 mph11 km/h
DayMostly cloudy and mild, with a high of 60°F16°C and morning low of 48°F9°C. Breezy from the W at 7 mph11 km/h. 13% chance of drizzle in the morning. Dry air. NightMostly cloudy, with a low around 49°F9°C. Light wind from the WSW around 6 mph10 km/h. 11% 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