Current Conditions

O'Fallon, Illinois

91°F33°C

Hot

Wind

SE 5 mph8 km/h

Humidity

36%

Cloud Cover

55%

As of Tuesday, September 8, 2026 at 7:43 PM CDT

Today's Outlook

Night

Partly cloudy, with a low around 83°F28°C. Light wind from the SSE around 6 mph9 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Hot	High 95°F35°C	Low 83°F28°C	Precip 0 in0 mm—	Cloud 67%	Wind SSE 5 mph8 km/h	Tuesday: Overcast and hot, with a high of 95°F35°C and morning low of 90°F32°C. Light wind from the SSE around 4 mph7 km/h. Heat risk in the afternoon. Tuesday Night: Partly cloudy, with a low around 83°F28°C. Light wind from the SSE around 6 mph9 km/h.
Drizzle	High 95°F35°CFeels 100°F38°C	Low 77°F25°C	Precip 0.04 in0.9 mm32%	Cloud 42%	Wind SW 6 mph9 km/h	Wednesday: Partly cloudy and hot, with a high of 95°F35°C and morning low of 77°F25°C — feels like 100°F38°C. Breezy from the WSW at 6 to 8 mph10 to 12 km/h. 20% chance of drizzle in the afternoon. Heat risk in the afternoon. Wednesday Night: Partly cloudy, with a low around 78°F25°C. Breezy from the S at 6 to 7 mph9 to 12 km/h. 32% chance of drizzle in the evening.
Rain	High 80°F27°C	Low 74°F23°C	Precip 0.51 in12.9 mm93%	Cloud 90%	Wind NNW 4 mph6 km/h	Thursday: Overcast and warm, with a high of 80°F27°C and morning low of 74°F23°C. Light wind from the WNW around 4 mph6 km/h. 93% chance of rain throughout the day. Heavy, humid air. Thursday Night: Overcast, with a low around 74°F23°C. Light wind from the NNE around 4 mph6 km/h. 75% chance of light rain throughout the night.
Showers	High 85°F30°CFeels 88°F31°C	Low 70°F21°C	Precip 0.13 in3.4 mm34%	Cloud 59%	Wind ESE 4 mph6 km/h	Friday: Mostly cloudy and warm, with a high of 85°F30°C and morning low of 70°F21°C. Light wind from the ESE around 4 mph6 km/h. 34% chance of light rain throughout the day. Humid. Friday Night: Partly cloudy, with a low around 70°F21°C. Light wind from the E around 4 mph6 km/h. 19% chance of drizzle before dawn.
Drizzle	High 90°F32°CFeels 93°F34°C	Low 70°F21°C	Precip 0.04 in1 mm14%	Cloud 43%	Wind SW 5 mph7 km/h	Saturday: Mostly cloudy and hot, with a high of 90°F32°C and morning low of 70°F21°C. Light wind from the WSW around 5 mph8 km/h. 14% chance of drizzle throughout the day. Humid. Saturday Night: Partly cloudy, with a low around 72°F22°C. Light wind from the SSW around 5 mph7 km/h. 10% chance of drizzle.
Clear	High 88°F31°C	Low 69°F21°C	Precip 0.01 in0.2 mm6%	Cloud 25%	Wind N 6 mph9 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 6 mph9 km/h. Sunday Night: Mostly clear, with a low around 72°F22°C. Breezy from the NNE at 6 to 7 mph9 to 11 km/h.
Clear	High 91°F33°C	Low 68°F20°C	Precip 0.02 in0.5 mm6%	Cloud 28%	Wind SE 8 mph12 km/h	Monday: Partly cloudy and hot, with a high of 91°F33°C and morning low of 68°F20°C. Breezy from the SSE at 8 to 9 mph12 to 14 km/h. Monday Night: Mostly clear, with a low around 70°F21°C. Breezy from the SE at 8 to 10 mph13 to 16 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	TuesdaySep 8	95°F35°C	83°F28°C	0 in0 mm· —	67%	Hot	SSE 5 mph8 km/h
DayOvercast and hot, with a high of 95°F35°C and morning low of 90°F32°C. Light wind from the SSE around 4 mph7 km/h. Heat risk in the afternoon. NightPartly cloudy, with a low around 83°F28°C. Light wind from the SSE around 6 mph9 km/h.
	WednesdaySep 9	95°F35°C Feels 100°F38°C	77°F25°C	0.04 in0.9 mm· 32%	42%	Drizzle	SW 6 mph9 km/h
DayPartly cloudy and hot, with a high of 95°F35°C and morning low of 77°F25°C — feels like 100°F38°C. Breezy from the WSW at 6 to 8 mph10 to 12 km/h. 20% chance of drizzle in the afternoon. Heat risk in the afternoon. NightPartly cloudy, with a low around 78°F25°C. Breezy from the S at 6 to 7 mph9 to 12 km/h. 32% chance of drizzle in the evening.
	ThursdaySep 10	80°F27°C	74°F23°C	0.51 in12.9 mm· 93%	90%	Rain	NNW 4 mph6 km/h
DayOvercast and warm, with a high of 80°F27°C and morning low of 74°F23°C. Light wind from the WNW around 4 mph6 km/h. 93% chance of rain throughout the day. Heavy, humid air. NightOvercast, with a low around 74°F23°C. Light wind from the NNE around 4 mph6 km/h. 75% chance of light rain throughout the night.
	FridaySep 11	85°F30°C Feels 88°F31°C	70°F21°C	0.13 in3.4 mm· 34%	59%	Showers	ESE 4 mph6 km/h
DayMostly cloudy and warm, with a high of 85°F30°C and morning low of 70°F21°C. Light wind from the ESE around 4 mph6 km/h. 34% chance of light rain throughout the day. Humid. NightPartly cloudy, with a low around 70°F21°C. Light wind from the E around 4 mph6 km/h. 19% chance of drizzle before dawn.
	SaturdaySep 12	90°F32°C Feels 93°F34°C	70°F21°C	0.04 in1 mm· 14%	43%	Drizzle	SW 5 mph7 km/h
DayMostly cloudy and hot, with a high of 90°F32°C and morning low of 70°F21°C. Light wind from the WSW around 5 mph8 km/h. 14% chance of drizzle throughout the day. Humid. NightPartly cloudy, with a low around 72°F22°C. Light wind from the SSW around 5 mph7 km/h. 10% chance of drizzle.
	SundaySep 13	88°F31°C	69°F21°C	0.01 in0.2 mm· 6%	25%	Clear	N 6 mph9 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 6 mph9 km/h. NightMostly clear, with a low around 72°F22°C. Breezy from the NNE at 6 to 7 mph9 to 11 km/h.
	MondaySep 14	91°F33°C	68°F20°C	0.02 in0.5 mm· 6%	28%	Clear	SE 8 mph12 km/h
DayPartly cloudy and hot, with a high of 91°F33°C and morning low of 68°F20°C. Breezy from the SSE at 8 to 9 mph12 to 14 km/h. NightMostly clear, with a low around 70°F21°C. Breezy from the SE at 8 to 10 mph13 to 16 km/h.
	TuesdaySep 15	94°F34°C	73°F23°C	0.03 in0.8 mm· 20%	34%	Drizzle	S 8 mph13 km/h
DayPartly cloudy and hot, with a high of 94°F34°C and morning low of 73°F23°C. Breezy from the SSW at 8 to 9 mph13 to 14 km/h. 10% chance of drizzle in the afternoon. NightPartly cloudy, with a low around 75°F24°C. Breezy from the S at 8 to 9 mph13 to 15 km/h. 20% chance of drizzle in the evening.
	WednesdaySep 16	92°F33°C Feels 95°F35°C	73°F23°C	0.07 in1.7 mm· 19%	47%	Drizzle	SSE 6 mph9 km/h
DayMostly cloudy and hot, with a high of 92°F33°C and morning low of 73°F23°C. Light wind from the S around 5 mph9 km/h. 19% chance of drizzle throughout the day. Humid. NightPartly cloudy, with a low around 75°F24°C. Breezy from the SSE at 6 to 7 mph10 to 11 km/h. 16% chance of drizzle throughout the night.
	ThursdaySep 17	93°F34°C	74°F24°C	0.06 in1.4 mm· 14%	31%	Drizzle	S 8 mph12 km/h
DayPartly cloudy and hot, with a high of 93°F34°C and morning low of 74°F24°C. Breezy from the SSW at 8 to 9 mph13 to 14 km/h. 10% chance of drizzle throughout the day. Heat risk in the afternoon. NightPartly cloudy, with a low around 76°F25°C. Breezy from the S at 7 to 8 mph12 to 13 km/h. 14% chance of drizzle throughout the night.
	FridaySep 18	87°F30°C	72°F22°C	0.13 in3.3 mm· 19%	39%	Showers	SW 8 mph12 km/h
DayPartly cloudy and hot, with a high of 87°F30°C and morning low of 72°F22°C. Breezy from the WSW at 8 mph12 km/h. 19% chance of drizzle throughout the day. NightPartly cloudy, with a low around 74°F24°C. Breezy from the SSW at 7 to 8 mph12 to 13 km/h. 18% chance of showers throughout the night.
	SaturdaySep 19	81°F27°C	66°F19°C	0.15 in3.9 mm· 20%	51%	Showers	NW 7 mph11 km/h
DayMostly cloudy and warm, with a high of 81°F27°C and morning low of 66°F19°C. Breezy from the NW at 7 to 8 mph12 to 13 km/h. 19% chance of showers throughout the day. NightPartly cloudy, with a low around 68°F20°C. Breezy from the NNW at 7 mph11 km/h. 20% chance of showers throughout the night.
	SundaySep 20	77°F25°C	61°F16°C	0.13 in3.2 mm· 22%	57%	Showers	N 7 mph11 km/h
DayMostly cloudy and warm, with a high of 77°F25°C and morning low of 61°F16°C. Breezy from the N at 7 mph11 km/h. 22% chance of showers throughout the day. NightMostly cloudy, with a low around 64°F18°C. Breezy from the NNE at 7 mph11 km/h. 15% chance of showers throughout the night.
	MondaySep 21	75°F24°C	58°F14°C	0.11 in2.7 mm· 13%	56%	Drizzle	NE 7 mph11 km/h
DayMostly cloudy and warm, with a high of 75°F24°C and morning low of 58°F14°C. Breezy from the NE at 7 mph11 km/h. 13% chance of drizzle throughout the day. NightMostly cloudy, with a low around 61°F16°C. Breezy from the NE at 6 to 7 mph10 to 11 km/h. 11% chance of drizzle throughout the night.
	TuesdaySep 22	76°F24°C	57°F14°C	0.09 in2.4 mm· 13%	55%	Showers	ENE 6 mph10 km/h
DayMostly cloudy and warm, with a high of 76°F24°C and morning low of 57°F14°C. Breezy from the NE at 6 to 7 mph10 to 11 km/h. 13% chance of showers throughout the day. Dry air. NightMostly cloudy, with a low around 59°F15°C. Light wind from the ENE around 6 mph10 km/h. 10% 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