Current Conditions

O'Fallon, Missouri

63°F17°C

Partly Cloudy

Wind

NE 7 mph11 km/h

Humidity

73%

Cloud Cover

72%

As of Wednesday, September 23, 2026 at 12:33 AM CDT

Today's Outlook

Day

Overcast and warm, with a high of 69°F21°C and morning low of 59°F15°C. Breezy from the NNE at 7 to 8 mph11 to 12 km/h.

Night

Mostly cloudy, with a low around 61°F16°C. Breezy from the NNE at 6 to 7 mph10 to 11 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Partly Cloudy	High 69°F21°C	Low 59°F15°C	Precip 0 in0.1 mm2%	Cloud 79%	Wind NNE 6 mph10 km/h	Wednesday: Overcast and warm, with a high of 69°F21°C and morning low of 59°F15°C. Breezy from the NNE at 7 to 8 mph11 to 12 km/h. Wednesday Night: Mostly cloudy, with a low around 61°F16°C. Breezy from the NNE at 6 to 7 mph10 to 11 km/h.
Cloudy	High 71°F22°C	Low 59°F15°C	Precip 0 in0 mm—	Cloud 81%	Wind NE 5 mph7 km/h	Thursday: Overcast and warm, with a high of 71°F22°C and morning low of 59°F15°C. Light wind from the NE around 5 mph8 km/h. Thursday Night: Mostly cloudy, with a low around 60°F16°C. Light wind from the NE around 4 mph7 km/h.
Cloudy	High 75°F24°C	Low 62°F16°C	Precip 0.01 in0.3 mm8%	Cloud 90%	Wind ENE 4 mph7 km/h	Friday: Overcast and warm, with a high of 75°F24°C and morning low of 62°F16°C. Light wind from the ENE around 4 mph7 km/h. Friday Night: Overcast, with a low around 62°F16°C. Light wind from the ENE around 4 mph6 km/h.
Light Rain	High 70°F21°C	Low 62°F17°C	Precip 0.11 in2.7 mm45%	Cloud 87%	Wind E 5 mph8 km/h	Saturday: Overcast and warm, with a high of 70°F21°C and morning low of 62°F17°C. Light wind from the ESE around 5 mph7 km/h. 45% chance of light rain throughout the day. Saturday Night: Overcast, with a low around 64°F18°C. Light wind from the E around 5 mph8 km/h. 39% chance of drizzle throughout the night.
Drizzle	High 75°F24°C	Low 61°F16°C	Precip 0.07 in1.8 mm34%	Cloud 60%	Wind E 4 mph7 km/h	Sunday: Mostly cloudy and warm, with a high of 75°F24°C and morning low of 61°F16°C. Light wind from the E around 4 mph6 km/h. 34% chance of drizzle throughout the day. Sunday Night: Mostly cloudy, with a low around 62°F16°C. Light wind from the ENE around 5 mph8 km/h. 24% chance of drizzle throughout the night.
Clear	High 79°F26°C	Low 58°F14°C	Precip 0.01 in0.2 mm5%	Cloud 35%	Wind ENE 4 mph7 km/h	Monday: Partly cloudy and warm, with a high of 79°F26°C and morning low of 58°F14°C. Light wind from the E around 4 mph6 km/h. Monday Night: Partly cloudy, with a low around 60°F16°C. Light wind from the ENE around 5 mph8 km/h.
Light Rain	High 78°F26°C	Low 59°F15°C	Precip 0.17 in4.4 mm32%	Cloud 75%	Wind SSE 7 mph11 km/h	Tuesday: Mostly cloudy and warm, with a high of 78°F26°C and morning low of 59°F15°C. Breezy from the SSE at 7 to 8 mph11 to 13 km/h. 29% chance of light rain throughout the day. Tuesday Night: Mostly cloudy, with a low around 61°F16°C. Breezy from the SSE at 7 to 8 mph11 to 13 km/h. 32% chance of light rain throughout the night.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 23	69°F21°C	59°F15°C	0 in0.1 mm· 2%	79%	Partly Cloudy	NNE 6 mph10 km/h
DayOvercast and warm, with a high of 69°F21°C and morning low of 59°F15°C. Breezy from the NNE at 7 to 8 mph11 to 12 km/h. NightMostly cloudy, with a low around 61°F16°C. Breezy from the NNE at 6 to 7 mph10 to 11 km/h.
	ThursdaySep 24	71°F22°C	59°F15°C	0 in0 mm· —	81%	Cloudy	NE 5 mph7 km/h
DayOvercast and warm, with a high of 71°F22°C and morning low of 59°F15°C. Light wind from the NE around 5 mph8 km/h. NightMostly cloudy, with a low around 60°F16°C. Light wind from the NE around 4 mph7 km/h.
	FridaySep 25	75°F24°C	62°F16°C	0.01 in0.3 mm· 8%	90%	Cloudy	ENE 4 mph7 km/h
DayOvercast and warm, with a high of 75°F24°C and morning low of 62°F16°C. Light wind from the ENE around 4 mph7 km/h. NightOvercast, with a low around 62°F16°C. Light wind from the ENE around 4 mph6 km/h.
	SaturdaySep 26	70°F21°C	62°F17°C	0.11 in2.7 mm· 45%	87%	Light Rain	E 5 mph8 km/h
DayOvercast and warm, with a high of 70°F21°C and morning low of 62°F17°C. Light wind from the ESE around 5 mph7 km/h. 45% chance of light rain throughout the day. NightOvercast, with a low around 64°F18°C. Light wind from the E around 5 mph8 km/h. 39% chance of drizzle throughout the night.
	SundaySep 27	75°F24°C	61°F16°C	0.07 in1.8 mm· 34%	60%	Drizzle	E 4 mph7 km/h
DayMostly cloudy and warm, with a high of 75°F24°C and morning low of 61°F16°C. Light wind from the E around 4 mph6 km/h. 34% chance of drizzle throughout the day. NightMostly cloudy, with a low around 62°F16°C. Light wind from the ENE around 5 mph8 km/h. 24% chance of drizzle throughout the night.
	MondaySep 28	79°F26°C	58°F14°C	0.01 in0.2 mm· 5%	35%	Clear	ENE 4 mph7 km/h
DayPartly cloudy and warm, with a high of 79°F26°C and morning low of 58°F14°C. Light wind from the E around 4 mph6 km/h. NightPartly cloudy, with a low around 60°F16°C. Light wind from the ENE around 5 mph8 km/h.
	TuesdaySep 29	78°F26°C	59°F15°C	0.17 in4.4 mm· 32%	75%	Light Rain	SSE 7 mph11 km/h
DayMostly cloudy and warm, with a high of 78°F26°C and morning low of 59°F15°C. Breezy from the SSE at 7 to 8 mph11 to 13 km/h. 29% chance of light rain throughout the day. NightMostly cloudy, with a low around 61°F16°C. Breezy from the SSE at 7 to 8 mph11 to 13 km/h. 32% chance of light rain throughout the night.
	WednesdaySep 30	73°F23°C	64°F18°C	0.43 in11 mm· 49%	77%	Light Rain	WSW 8 mph12 km/h
DayMostly cloudy and warm, with a high of 73°F23°C and morning low of 64°F18°C. Breezy from the W at 8 to 9 mph13 to 14 km/h. 49% chance of light rain throughout the day. NightMostly cloudy, with a low around 64°F18°C. Breezy from the SW at 7 to 8 mph12 to 12 km/h. 48% chance of light rain throughout the night.
	ThursdayOct 1	74°F23°C	59°F15°C	0.21 in5.4 mm· 24%	53%	Showers	WNW 7 mph12 km/h
DayMostly cloudy and warm, with a high of 74°F23°C and morning low of 59°F15°C. Breezy from the WNW at 8 to 9 mph13 to 14 km/h. 23% chance of showers throughout the day. NightMostly cloudy, with a low around 61°F16°C. Breezy from the WNW at 7 mph11 km/h. 24% chance of showers throughout the night.
	FridayOct 2	75°F24°C	57°F14°C	0.15 in3.8 mm· 19%	46%	Showers	SSW 6 mph10 km/h
DayPartly cloudy and warm, with a high of 75°F24°C and morning low of 57°F14°C. Breezy from the SW at 7 mph10 km/h. 19% chance of showers throughout the day. NightPartly cloudy, with a low around 59°F15°C. Breezy from the S at 6 to 7 mph10 to 11 km/h. 18% chance of showers throughout the night.
	SaturdayOct 3	76°F24°C	58°F15°C	0.1 in2.5 mm· 14%	55%	Drizzle	SSW 7 mph12 km/h
DayMostly cloudy and warm, with a high of 76°F24°C and morning low of 58°F15°C. Breezy from the SSW at 8 mph12 km/h. 14% chance of drizzle throughout the day. NightMostly cloudy, with a low around 60°F16°C. Breezy from the S at 7 to 8 mph11 to 12 km/h. 14% chance of drizzle throughout the night.
	SundayOct 4	72°F22°C	57°F14°C	0.11 in2.7 mm· 16%	50%	Drizzle	WNW 7 mph12 km/h
DayMostly cloudy and warm, with a high of 72°F22°C and morning low of 57°F14°C. Breezy from the WNW at 8 to 9 mph13 to 14 km/h. 14% chance of drizzle throughout the day. NightPartly cloudy, with a low around 59°F15°C. Breezy from the W at 7 mph11 km/h. 16% chance of drizzle throughout the night.
	MondayOct 5	71°F21°C	53°F12°C	0.1 in2.5 mm· 14%	44%	Showers	WNW 7 mph11 km/h
DayPartly cloudy and warm, with a high of 71°F21°C and morning low of 53°F12°C. Breezy from the WNW at 7 mph11 km/h. 12% chance of drizzle throughout the day. Dry air. NightPartly cloudy, with a low around 55°F13°C. Breezy from the NW at 6 to 7 mph10 to 11 km/h. 14% chance of showers throughout the night.
	TuesdayOct 6	70°F21°C	52°F11°C	0.11 in2.7 mm· 12%	43%	Showers	WNW 7 mph11 km/h
DayPartly cloudy and warm, with a high of 70°F21°C and morning low of 52°F11°C. Breezy from the WNW at 7 to 8 mph11 to 12 km/h. 12% chance of drizzle throughout the day. Dry air. NightPartly cloudy, with a low around 54°F12°C. Breezy from the WNW at 7 mph11 km/h. 10% chance of showers throughout the night.
	WednesdayOct 7	69°F21°C	51°F10°C	0.06 in1.6 mm· 11%	32%	Drizzle	NW 7 mph11 km/h
DayPartly cloudy and warm, with a high of 69°F21°C and morning low of 51°F10°C. Breezy from the NW at 7 to 8 mph12 to 13 km/h. Dry air. NightPartly cloudy, with a low around 53°F12°C. Breezy from the NW at 7 mph11 km/h. 11% chance of drizzle throughout the night.

Nearby Cities

Saint Peters4 mi6 km Wentzville8 mi13 km Saint Charles12 mi19 km Chesterfield12 mi20 km Wildwood16 mi26 km Maryland Heights16 mi26 km

About This Forecast

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Coordinates: 38.8106°N, 90.6998°W·Elevation: 165m·Timezone: America/Chicago·Population: 85,040