Current Conditions

O'Fallon, Illinois

79°F26°C

Partly Cloudy

Wind

NE 4 mph7 km/h

Humidity

43%

Cloud Cover

81%

As of Thursday, July 23, 2026 at 12:53 PM CDT

Today's Outlook

Day

Mostly cloudy and warm, with a high of 81°F27°C and morning low of 66°F19°C. Light wind from the ENE around 5 mph7 km/h.

Night

Overcast, with a low around 73°F23°C. Light wind from the E around 4 mph7 km/h.

7-Day Forecast

Day	Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
ThursdayJul 23	Partly Cloudy	High 81°F27°C	Low 66°F19°C	Precip 0 in0 mm—	Cloud 74%	Wind ENE 5 mph7 km/h	Thursday: Mostly cloudy and warm, with a high of 81°F27°C and morning low of 66°F19°C. Light wind from the ENE around 5 mph7 km/h. Thursday Night: Overcast, with a low around 73°F23°C. Light wind from the E around 4 mph7 km/h.
FridayJul 24	Light Rain	High 71°F22°C	Low 68°F20°C	Precip 0.26 in6.7 mm87%	Cloud 91%	Wind SE 4 mph6 km/h	Friday: Overcast and warm, with a high of 71°F22°C. Light wind from the SE around 3 mph5 km/h. 87% chance of light rain throughout the day. Friday Night: Overcast, with a low around 69°F21°C. Light wind from the ESE around 4 mph7 km/h. 56% chance of light rain in the evening.
SaturdayJul 25	Showers	High 87°F31°CFeels 96°F36°C	Low 68°F20°C	Precip 0.14 in3.5 mm60%	Cloud 67%	Wind SSE 4 mph7 km/h	Saturday: Mostly cloudy and hot, with a high of 87°F31°C and morning low of 69°F21°C — feels like 95°F35°C. Light wind from the S around 4 mph7 km/h. 60% chance of light rain throughout the day. Heat risk in the afternoon. Saturday Night: Mostly cloudy, with a low around 68°F20°C. Light wind from the SSE around 4 mph7 km/h. 55% chance of showers overnight.
SundayJul 26	Hot	High 99°F37°CFeels 111°F44°C	Low 77°F25°C	Precip 0.01 in0.2 mm5%	Cloud 46%	Wind S 4 mph7 km/h	Sunday: Mostly cloudy and hot, with a high of 99°F37°C and morning low of 77°F25°C — feels like 111°F44°C. Light wind from the SW around 4 mph6 km/h. Heat risk in the afternoon. Sunday Night: Partly cloudy, with a low around 77°F25°C. Light wind from the S around 4 mph7 km/h.
MondayJul 27	Drizzle	High 98°F37°CFeels 107°F42°C	Low 80°F27°C	Precip 0.04 in0.9 mm10%	Cloud 48%	Wind SSW 7 mph11 km/h	Monday: Mostly cloudy and hot, with a high of 98°F37°C and morning low of 80°F27°C — feels like 108°F42°C. Breezy from the SW at 7 to 9 mph11 to 14 km/h. 10% chance of drizzle throughout the day. Heat risk in the afternoon. Monday Night: Partly cloudy, with a low around 81°F27°C. Breezy from the SSW at 7 to 8 mph11 to 12 km/h.
TuesdayJul 28	Drizzle	High 98°F37°CFeels 105°F41°C	Low 82°F28°CFeels 87°F30°C	Precip 0.03 in0.8 mm15%	Cloud 34%	Wind NW 7 mph11 km/h	Tuesday: Partly cloudy and hot, with a high of 98°F37°C and morning low of 82°F28°C — feels like 106°F41°C. Breezy from the NW at 7 mph11 km/h. 11% chance of drizzle in the afternoon. Heat risk in the afternoon. Tuesday Night: Partly cloudy, with a low around 83°F28°C. Breezy from the WNW at 7 to 8 mph11 to 13 km/h. 15% chance of drizzle in the evening.
WednesdayJul 29	Hot	High 95°F35°C	Low 76°F24°C	Precip 0.02 in0.6 mm7%	Cloud 22%	Wind NE 5 mph9 km/h	Wednesday: Mostly clear and hot, with a high of 95°F35°C and morning low of 76°F24°C. Light wind from the NE around 5 mph8 km/h. Heat risk in the afternoon. Wednesday Night: Mostly clear, with a low around 78°F26°C. Light wind from the NE around 6 mph9 km/h.

15-Day Forecast

	Day	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Condition	Wind (mph)
	ThursdayJul 23	81°F27°C	66°F19°C	0 in0 mm· —	74%	Partly Cloudy	ENE 5 mph7 km/h
DayMostly cloudy and warm, with a high of 81°F27°C and morning low of 66°F19°C. Light wind from the ENE around 5 mph7 km/h. NightOvercast, with a low around 73°F23°C. Light wind from the E around 4 mph7 km/h.
	FridayJul 24	71°F22°C	68°F20°C	0.26 in6.7 mm· 87%	91%	Light Rain	SE 4 mph6 km/h
DayOvercast and warm, with a high of 71°F22°C. Light wind from the SE around 3 mph5 km/h. 87% chance of light rain throughout the day. NightOvercast, with a low around 69°F21°C. Light wind from the ESE around 4 mph7 km/h. 56% chance of light rain in the evening.
	SaturdayJul 25	87°F31°C Feels 96°F36°C	68°F20°C	0.14 in3.5 mm· 60%	67%	Showers	SSE 4 mph7 km/h
DayMostly cloudy and hot, with a high of 87°F31°C and morning low of 69°F21°C — feels like 95°F35°C. Light wind from the S around 4 mph7 km/h. 60% chance of light rain throughout the day. Heat risk in the afternoon. NightMostly cloudy, with a low around 68°F20°C. Light wind from the SSE around 4 mph7 km/h. 55% chance of showers overnight.
	SundayJul 26	99°F37°C Feels 111°F44°C	77°F25°C	0.01 in0.2 mm· 5%	46%	Hot	S 4 mph7 km/h
DayMostly cloudy and hot, with a high of 99°F37°C and morning low of 77°F25°C — feels like 111°F44°C. Light wind from the SW around 4 mph6 km/h. Heat risk in the afternoon. NightPartly cloudy, with a low around 77°F25°C. Light wind from the S around 4 mph7 km/h.
	MondayJul 27	98°F37°C Feels 107°F42°C	80°F27°C	0.04 in0.9 mm· 10%	48%	Drizzle	SSW 7 mph11 km/h
DayMostly cloudy and hot, with a high of 98°F37°C and morning low of 80°F27°C — feels like 108°F42°C. Breezy from the SW at 7 to 9 mph11 to 14 km/h. 10% chance of drizzle throughout the day. Heat risk in the afternoon. NightPartly cloudy, with a low around 81°F27°C. Breezy from the SSW at 7 to 8 mph11 to 12 km/h.
	TuesdayJul 28	98°F37°C Feels 105°F41°C	82°F28°C Feels 87°F30°C	0.03 in0.8 mm· 15%	34%	Drizzle	NW 7 mph11 km/h
DayPartly cloudy and hot, with a high of 98°F37°C and morning low of 82°F28°C — feels like 106°F41°C. Breezy from the NW at 7 mph11 km/h. 11% chance of drizzle in the afternoon. Heat risk in the afternoon. NightPartly cloudy, with a low around 83°F28°C. Breezy from the WNW at 7 to 8 mph11 to 13 km/h. 15% chance of drizzle in the evening.
	WednesdayJul 29	95°F35°C	76°F24°C	0.02 in0.6 mm· 7%	22%	Hot	NE 5 mph9 km/h
DayMostly clear and hot, with a high of 95°F35°C and morning low of 76°F24°C. Light wind from the NE around 5 mph8 km/h. Heat risk in the afternoon. NightMostly clear, with a low around 78°F26°C. Light wind from the NE around 6 mph9 km/h.
	ThursdayJul 30	95°F35°C	75°F24°C	0.02 in0.5 mm· 11%	27%	Drizzle	E 5 mph8 km/h
DayPartly cloudy and hot, with a high of 95°F35°C and morning low of 75°F24°C. Light wind from the ENE around 5 mph8 km/h. Heat risk in the afternoon. NightMostly clear, with a low around 76°F25°C. Light wind from the E around 5 mph9 km/h. 11% chance of drizzle in the evening.
	FridayJul 31	93°F34°C	75°F24°C	0.08 in2 mm· 22%	44%	Showers	SE 5 mph8 km/h
DayPartly cloudy and hot, with a high of 93°F34°C and morning low of 75°F24°C. Light wind from the SSE around 5 mph8 km/h. 19% chance of drizzle throughout the day. Humid. NightPartly cloudy, with a low around 76°F25°C. Light wind from the SE around 5 mph8 km/h. 22% chance of showers throughout the night.
	SaturdayAug 1	95°F35°C	74°F24°C	0.09 in2.2 mm· 11%	29%	Drizzle	NW 5 mph9 km/h
DayPartly cloudy and hot, with a high of 95°F35°C and morning low of 74°F24°C. Light wind from the NW around 5 mph9 km/h. 11% chance of drizzle throughout the day. Humid. NightPartly cloudy, with a low around 76°F24°C. Light wind from the SE around 5 mph8 km/h. 10% chance of drizzle throughout the night.
	SundayAug 2	94°F35°C	74°F23°C	0.03 in0.7 mm· 7%	32%	Clear	SSE 6 mph9 km/h
DayPartly cloudy and hot, with a high of 94°F35°C and morning low of 74°F23°C. Light wind from the S around 6 mph9 km/h. Humid. NightPartly cloudy, with a low around 76°F24°C. Light wind from the SSE around 6 mph9 km/h.
	MondayAug 3	94°F35°C	74°F24°C	0.07 in1.7 mm· 15%	37%	Showers	S 6 mph10 km/h
DayPartly cloudy and hot, with a high of 94°F35°C and morning low of 74°F24°C. Light wind from the SSW around 6 mph10 km/h. 10% chance of drizzle around midday. Humid. NightPartly cloudy, with a low around 76°F24°C. Light wind from the S around 6 mph10 km/h. 15% chance of showers in the evening.
	TuesdayAug 4	94°F34°C	75°F24°C	0.09 in2.4 mm· 15%	46%	Drizzle	SSW 6 mph10 km/h
DayMostly cloudy and hot, with a high of 94°F34°C and morning low of 75°F24°C. Breezy from the SW at 6 to 7 mph10 to 11 km/h. 11% chance of drizzle throughout the day. Humid. NightPartly cloudy, with a low around 76°F25°C. Breezy from the SSW at 6 to 7 mph10 to 11 km/h. 15% chance of drizzle throughout the night.
	WednesdayAug 5	92°F33°C	74°F24°C	0.1 in2.5 mm· 15%	47%	Drizzle	SW 6 mph10 km/h
DayMostly cloudy and hot, with a high of 92°F33°C and morning low of 74°F24°C. Breezy from the SW at 6 to 7 mph10 to 11 km/h. 15% chance of drizzle throughout the day. Humid. NightPartly cloudy, with a low around 76°F24°C. Light wind from the SSW around 6 mph10 km/h. 15% chance of drizzle throughout the night.
	ThursdayAug 6	90°F32°C	73°F23°C	0.07 in1.9 mm· 14%	46%	Drizzle	SW 6 mph10 km/h
DayMostly cloudy and hot, with a high of 90°F32°C and morning low of 73°F23°C. Breezy from the WSW at 6 to 7 mph10 to 11 km/h. 11% chance of drizzle throughout the day. NightPartly cloudy, with a low around 75°F24°C. Light wind from the SSW around 6 mph10 km/h. 14% chance of drizzle throughout the night.

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