Current Conditions

O'Fallon, Illinois

76°F24°C

Drizzle

Wind

SSE 4 mph7 km/h

Humidity

86%

Cloud Cover

80%

As of Thursday, August 13, 2026 at 2:31 AM CDT

Today's Outlook

Day

Overcast and hot, with a high of 94°F35°C and morning low of 76°F25°C — feels like 104°F40°C. Light wind from the S around 5 mph8 km/h. 16% chance of drizzle throughout the day. Heat risk in the afternoon.

Night

Overcast, with a low around 76°F24°C. Breezy from the SE at 6 to 8 mph10 to 13 km/h. 19% chance of drizzle throughout the night.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Drizzle	High 94°F35°CFeels 104°F40°C	Low 76°F24°C	Precip 0.05 in1.3 mm19%	Cloud 87%	Wind SSE 5 mph9 km/h	Thursday: Overcast and hot, with a high of 94°F35°C and morning low of 76°F25°C — feels like 104°F40°C. Light wind from the S around 5 mph8 km/h. 16% chance of drizzle throughout the day. Heat risk in the afternoon. Thursday Night: Overcast, with a low around 76°F24°C. Breezy from the SE at 6 to 8 mph10 to 13 km/h. 19% chance of drizzle throughout the night.
Hot	High 96°F35°CFeels 105°F40°C	Low 79°F26°C	Precip 0.02 in0.4 mm8%	Cloud 75%	Wind S 5 mph9 km/h	Friday: Overcast and hot, with a high of 96°F35°C and morning low of 79°F26°C — feels like 104°F40°C. Light wind from the S around 4 mph7 km/h. Heat risk in the afternoon. Friday Night: Mostly cloudy, with a low around 81°F27°C. Breezy from the SSE at 7 to 9 mph10 to 14 km/h.
Drizzle	High 97°F36°CFeels 104°F40°C	Low 80°F27°C	Precip 0.04 in0.9 mm16%	Cloud 60%	Wind S 6 mph9 km/h	Saturday: Mostly cloudy and hot, with a high of 97°F36°C and morning low of 80°F27°C — feels like 104°F40°C. Light wind from the SW around 5 mph8 km/h. 16% chance of drizzle in the morning. Heat risk in the afternoon. Saturday Night: Partly cloudy, with a low around 82°F28°C. Breezy from the S at 6 to 7 mph9 to 11 km/h. 10% chance of drizzle before dawn.
Drizzle	High 99°F37°CFeels 105°F40°C	Low 81°F27°CFeels 84°F29°C	Precip 0.03 in0.7 mm16%	Cloud 43%	Wind W 7 mph11 km/h	Sunday: Partly cloudy and hot, with a high of 99°F37°C and morning low of 81°F27°C. Breezy from the W at 7 mph11 km/h. 12% chance of drizzle in the afternoon. Heat risk in the afternoon. Sunday Night: Partly cloudy, with a low around 83°F28°C. Breezy from the W at 7 mph11 km/h. 16% chance of drizzle in the evening.
Showers	High 89°F32°CFeels 92°F33°C	Low 75°F24°C	Precip 0.06 in1.6 mm18%	Cloud 53%	Wind NNW 6 mph10 km/h	Monday: Mostly cloudy and hot, with a high of 89°F32°C and morning low of 75°F24°C. Breezy from the NNW at 6 to 7 mph10 to 12 km/h. Humid. Monday Night: Mostly cloudy, with a low around 77°F25°C. Light wind from the N around 6 mph9 km/h. 18% chance of showers overnight.
Clear	High 93°F34°C	Low 71°F22°C	Precip 0.02 in0.6 mm7%	Cloud 24%	Wind ESE 4 mph7 km/h	Tuesday: Mostly clear and hot, with a high of 93°F34°C and morning low of 71°F22°C. Light wind from the SE around 4 mph6 km/h. Humid. Tuesday Night: Partly cloudy, with a low around 72°F22°C. Breezy from the E at 5 to 7 mph8 to 11 km/h.
Drizzle	High 98°F37°C	Low 76°F24°C	Precip 0.05 in1.2 mm16%	Cloud 52%	Wind S 7 mph12 km/h	Wednesday: Mostly cloudy and hot, with a high of 98°F37°C and morning low of 76°F24°C. Breezy from the SSW at 7 to 9 mph12 to 14 km/h. 10% chance of drizzle. Heat risk in the afternoon. Wednesday Night: Partly cloudy, with a low around 77°F25°C. Breezy from the SSE at 7 to 8 mph12 to 12 km/h. 16% chance of drizzle throughout the night.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	ThursdayAug 13	94°F35°C Feels 104°F40°C	76°F24°C	0.05 in1.3 mm· 19%	87%	Drizzle	SSE 5 mph9 km/h
DayOvercast and hot, with a high of 94°F35°C and morning low of 76°F25°C — feels like 104°F40°C. Light wind from the S around 5 mph8 km/h. 16% chance of drizzle throughout the day. Heat risk in the afternoon. NightOvercast, with a low around 76°F24°C. Breezy from the SE at 6 to 8 mph10 to 13 km/h. 19% chance of drizzle throughout the night.
	FridayAug 14	96°F35°C Feels 105°F40°C	79°F26°C	0.02 in0.4 mm· 8%	75%	Hot	S 5 mph9 km/h
DayOvercast and hot, with a high of 96°F35°C and morning low of 79°F26°C — feels like 104°F40°C. Light wind from the S around 4 mph7 km/h. Heat risk in the afternoon. NightMostly cloudy, with a low around 81°F27°C. Breezy from the SSE at 7 to 9 mph10 to 14 km/h.
	SaturdayAug 15	97°F36°C Feels 104°F40°C	80°F27°C	0.04 in0.9 mm· 16%	60%	Drizzle	S 6 mph9 km/h
DayMostly cloudy and hot, with a high of 97°F36°C and morning low of 80°F27°C — feels like 104°F40°C. Light wind from the SW around 5 mph8 km/h. 16% chance of drizzle in the morning. Heat risk in the afternoon. NightPartly cloudy, with a low around 82°F28°C. Breezy from the S at 6 to 7 mph9 to 11 km/h. 10% chance of drizzle before dawn.
	SundayAug 16	99°F37°C Feels 105°F40°C	81°F27°C Feels 84°F29°C	0.03 in0.7 mm· 16%	43%	Drizzle	W 7 mph11 km/h
DayPartly cloudy and hot, with a high of 99°F37°C and morning low of 81°F27°C. Breezy from the W at 7 mph11 km/h. 12% chance of drizzle in the afternoon. Heat risk in the afternoon. NightPartly cloudy, with a low around 83°F28°C. Breezy from the W at 7 mph11 km/h. 16% chance of drizzle in the evening.
	MondayAug 17	89°F32°C Feels 92°F33°C	75°F24°C	0.06 in1.6 mm· 18%	53%	Showers	NNW 6 mph10 km/h
DayMostly cloudy and hot, with a high of 89°F32°C and morning low of 75°F24°C. Breezy from the NNW at 6 to 7 mph10 to 12 km/h. Humid. NightMostly cloudy, with a low around 77°F25°C. Light wind from the N around 6 mph9 km/h. 18% chance of showers overnight.
	TuesdayAug 18	93°F34°C	71°F22°C	0.02 in0.6 mm· 7%	24%	Clear	ESE 4 mph7 km/h
DayMostly clear and hot, with a high of 93°F34°C and morning low of 71°F22°C. Light wind from the SE around 4 mph6 km/h. Humid. NightPartly cloudy, with a low around 72°F22°C. Breezy from the E at 5 to 7 mph8 to 11 km/h.
	WednesdayAug 19	98°F37°C	76°F24°C	0.05 in1.2 mm· 16%	52%	Drizzle	S 7 mph12 km/h
DayMostly cloudy and hot, with a high of 98°F37°C and morning low of 76°F24°C. Breezy from the SSW at 7 to 9 mph12 to 14 km/h. 10% chance of drizzle. Heat risk in the afternoon. NightPartly cloudy, with a low around 77°F25°C. Breezy from the SSE at 7 to 8 mph12 to 12 km/h. 16% chance of drizzle throughout the night.
	ThursdayAug 20	91°F33°C	75°F24°C	0.08 in2 mm· 14%	44%	Showers	NNW 6 mph10 km/h
DayMostly cloudy and hot, with a high of 91°F33°C and morning low of 75°F24°C. Light wind from the NW around 6 mph10 km/h. 12% chance of drizzle in the morning. Humid. NightPartly cloudy, with a low around 77°F25°C. Breezy from the N at 7 mph11 km/h. 14% chance of showers throughout the night.
	FridayAug 21	88°F31°C	71°F22°C	0.09 in2.3 mm· 12%	41%	Drizzle	NE 6 mph9 km/h
DayPartly cloudy and hot, with a high of 88°F31°C and morning low of 71°F22°C. Light wind from the N around 6 mph9 km/h. 12% chance of drizzle throughout the day. NightPartly cloudy, with a low around 73°F23°C. Light wind from the NE around 6 mph10 km/h. 12% chance of drizzle throughout the night.
	SaturdayAug 22	89°F32°C	70°F21°C	0.04 in1.1 mm· 9%	35%	Clear	ENE 6 mph9 km/h
DayPartly cloudy and hot, with a high of 89°F32°C and morning low of 70°F21°C. Light wind from the NE around 6 mph9 km/h. NightPartly cloudy, with a low around 71°F22°C. Light wind from the ENE around 6 mph9 km/h.
	SundayAug 23	91°F33°C	69°F21°C	0.03 in0.8 mm· 7%	28%	Clear	E 6 mph9 km/h
DayPartly cloudy and hot, with a high of 91°F33°C and morning low of 69°F21°C. Light wind from the ESE around 6 mph9 km/h. NightPartly cloudy, with a low around 71°F22°C. Light wind from the E around 6 mph9 km/h.
	MondayAug 24	93°F34°C	71°F22°C	0.02 in0.4 mm· 8%	31%	Clear	E 6 mph9 km/h
DayPartly cloudy and hot, with a high of 93°F34°C and morning low of 71°F22°C. Light wind from the ESE around 6 mph9 km/h. NightPartly cloudy, with a low around 73°F23°C. Light wind from the E around 6 mph9 km/h.
	TuesdayAug 25	92°F33°C	71°F22°C	0.02 in0.6 mm· 8%	35%	Clear	E 6 mph9 km/h
DayPartly cloudy and hot, with a high of 92°F33°C and morning low of 71°F22°C. Light wind from the ENE around 6 mph9 km/h. NightPartly cloudy, with a low around 73°F23°C. Light wind from the E around 6 mph9 km/h.
	WednesdayAug 26	91°F33°C	71°F22°C	0.04 in1 mm· 10%	42%	Drizzle	E 6 mph9 km/h
DayPartly cloudy and hot, with a high of 91°F33°C and morning low of 71°F22°C. Light wind from the ENE around 6 mph9 km/h. NightPartly cloudy, with a low around 73°F23°C. Light wind from the E around 6 mph9 km/h. 10% chance of drizzle throughout the night.
	ThursdayAug 27	90°F32°C	71°F22°C	0.04 in1.1 mm· 11%	47%	Drizzle	E 6 mph9 km/h
DayMostly cloudy and hot, with a high of 90°F32°C and morning low of 71°F22°C. Light wind from the E around 5 mph9 km/h. NightPartly cloudy, with a low around 73°F23°C. Light wind from the E around 6 mph9 km/h. 11% 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

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Coordinates: 38.5923°N, 89.9112°W·Elevation: 167m·Timezone: America/Chicago·Population: 29,002