Current Conditions

O'Fallon, Missouri

95°F35°C

Hot

Feels like100°F38°C

Wind

S 5 mph7 km/h

Humidity

42%

Cloud Cover

21%

As of Wednesday, September 2, 2026 at 7:24 PM CDT

Today's Outlook

Night

Mostly clear, with a low around 86°F30°C. Breezy from the S at 6 to 7 mph10 to 12 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Hot	High 100°F38°C	Low 86°F30°CFeels 90°F32°C	Precip 0 in0 mm—	Cloud 21%	Wind SSW 6 mph10 km/h	Wednesday: Partly cloudy and hot, with a high of 100°F38°C. Light wind from the SSW around 6 mph10 km/h. Heat risk in the afternoon. Wednesday Night: Mostly clear, with a low around 86°F30°C. Breezy from the S at 6 to 7 mph10 to 12 km/h.
Hot	High 100°F38°C	Low 77°F25°C	Precip 0 in0 mm—	Cloud 7%	Wind SSW 7 mph11 km/h	Thursday: Mostly clear and hot, with a high of 100°F38°C and morning low of 77°F25°C. Breezy from the SSW at 7 mph11 km/h. Heat risk in the afternoon. Thursday Night: Mostly clear, with a low around 80°F27°C. Breezy from the S at 7 to 8 mph11 to 13 km/h.
Hot	High 100°F38°C	Low 76°F25°C	Precip 0 in0 mm—	Cloud 8%	Wind SSW 5 mph8 km/h	Friday: Mostly clear and hot, with a high of 100°F38°C and morning low of 76°F25°C. Light wind from the SW around 4 mph7 km/h. Heat risk in the afternoon. Friday Night: Mostly clear, with a low around 79°F26°C. Breezy from the S at 5 to 7 mph9 to 12 km/h.
Drizzle	High 101°F38°C	Low 78°F26°C	Precip 0.02 in0.6 mm20%	Cloud 32%	Wind SE 4 mph6 km/h	Saturday: Partly cloudy and hot, with a high of 101°F38°C and morning low of 78°F26°C. Light wind from the WNW around 3 mph5 km/h. 18% chance of drizzle in the afternoon. Heat risk in the afternoon. Saturday Night: Partly cloudy, with a low around 80°F27°C. Light wind from the SE around 5 mph8 km/h. 20% chance of drizzle in the evening.
Drizzle	High 94°F34°CFeels 98°F37°C	Low 76°F25°C	Precip 0.03 in0.7 mm22%	Cloud 47%	Wind ENE 6 mph9 km/h	Sunday: Partly cloudy and hot, with a high of 94°F34°C and morning low of 76°F25°C. Light wind from the ENE around 5 mph9 km/h. 22% chance of drizzle in the afternoon. Heat risk in the afternoon. Sunday Night: Partly cloudy, with a low around 79°F26°C. Breezy from the ENE at 6 to 7 mph9 to 11 km/h. 16% chance of drizzle in the evening.
Clear	High 93°F34°C	Low 73°F23°C	Precip 0.02 in0.5 mm8%	Cloud 31%	Wind ESE 6 mph9 km/h	Monday: Partly cloudy and hot, with a high of 93°F34°C and morning low of 73°F23°C. Light wind from the ESE around 6 mph9 km/h. Monday Night: Partly cloudy, with a low around 75°F24°C. Breezy from the ESE at 6 to 7 mph10 to 11 km/h.
Hot	High 99°F37°C	Low 73°F23°C	Precip 0 in0 mm—	Cloud 23%	Wind SSE 7 mph11 km/h	Tuesday: Partly cloudy and hot, with a high of 99°F37°C and morning low of 73°F23°C. Breezy from the S at 6 to 7 mph10 to 12 km/h. Heat risk in the afternoon. Tuesday Night: Mostly clear, with a low around 75°F24°C. Breezy from the SSE at 7 to 9 mph12 to 15 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 2	100°F38°C	86°F30°C Feels 90°F32°C	0 in0 mm· —	21%	Hot	SSW 6 mph10 km/h
DayPartly cloudy and hot, with a high of 100°F38°C. Light wind from the SSW around 6 mph10 km/h. Heat risk in the afternoon. NightMostly clear, with a low around 86°F30°C. Breezy from the S at 6 to 7 mph10 to 12 km/h.
	ThursdaySep 3	100°F38°C	77°F25°C	0 in0 mm· —	7%	Hot	SSW 7 mph11 km/h
DayMostly clear and hot, with a high of 100°F38°C and morning low of 77°F25°C. Breezy from the SSW at 7 mph11 km/h. Heat risk in the afternoon. NightMostly clear, with a low around 80°F27°C. Breezy from the S at 7 to 8 mph11 to 13 km/h.
	FridaySep 4	100°F38°C	76°F25°C	0 in0 mm· —	8%	Hot	SSW 5 mph8 km/h
DayMostly clear and hot, with a high of 100°F38°C and morning low of 76°F25°C. Light wind from the SW around 4 mph7 km/h. Heat risk in the afternoon. NightMostly clear, with a low around 79°F26°C. Breezy from the S at 5 to 7 mph9 to 12 km/h.
	SaturdaySep 5	101°F38°C	78°F26°C	0.02 in0.6 mm· 20%	32%	Drizzle	SE 4 mph6 km/h
DayPartly cloudy and hot, with a high of 101°F38°C and morning low of 78°F26°C. Light wind from the WNW around 3 mph5 km/h. 18% chance of drizzle in the afternoon. Heat risk in the afternoon. NightPartly cloudy, with a low around 80°F27°C. Light wind from the SE around 5 mph8 km/h. 20% chance of drizzle in the evening.
	SundaySep 6	94°F34°C Feels 98°F37°C	76°F25°C	0.03 in0.7 mm· 22%	47%	Drizzle	ENE 6 mph9 km/h
DayPartly cloudy and hot, with a high of 94°F34°C and morning low of 76°F25°C. Light wind from the ENE around 5 mph9 km/h. 22% chance of drizzle in the afternoon. Heat risk in the afternoon. NightPartly cloudy, with a low around 79°F26°C. Breezy from the ENE at 6 to 7 mph9 to 11 km/h. 16% chance of drizzle in the evening.
	MondaySep 7	93°F34°C	73°F23°C	0.02 in0.5 mm· 8%	31%	Clear	ESE 6 mph9 km/h
DayPartly cloudy and hot, with a high of 93°F34°C and morning low of 73°F23°C. Light wind from the ESE around 6 mph9 km/h. NightPartly cloudy, with a low around 75°F24°C. Breezy from the ESE at 6 to 7 mph10 to 11 km/h.
	TuesdaySep 8	99°F37°C	73°F23°C	0 in0 mm· —	23%	Hot	SSE 7 mph11 km/h
DayPartly cloudy and hot, with a high of 99°F37°C and morning low of 73°F23°C. Breezy from the S at 6 to 7 mph10 to 12 km/h. Heat risk in the afternoon. NightMostly clear, with a low around 75°F24°C. Breezy from the SSE at 7 to 9 mph12 to 15 km/h.
	WednesdaySep 9	98°F37°C	80°F26°C	0.02 in0.5 mm· 15%	27%	Drizzle	SSW 8 mph13 km/h
DayPartly cloudy and hot, with a high of 98°F37°C and morning low of 80°F26°C. Breezy from the SW at 8 mph12 km/h. Heat risk in the afternoon. NightPartly cloudy, with a low around 81°F27°C. Breezy from the S at 8 to 9 mph13 to 15 km/h. 15% chance of drizzle in the evening.
	ThursdaySep 10	93°F34°C	77°F25°C	0.09 in2.2 mm· 16%	43%	Showers	SW 7 mph11 km/h
DayPartly cloudy and hot, with a high of 93°F34°C and morning low of 77°F25°C. Breezy from the WSW at 7 mph11 km/h. 16% chance of showers throughout the day. Heat risk in the afternoon. NightPartly cloudy, with a low around 80°F27°C. Breezy from the SSW at 7 to 8 mph11 to 13 km/h. 13% chance of drizzle throughout the night.
	FridaySep 11	90°F32°C	72°F22°C	0.09 in2.3 mm· 15%	37%	Showers	S 6 mph10 km/h
DayPartly cloudy and hot, with a high of 90°F32°C and morning low of 72°F22°C. Breezy from the SSW at 6 to 7 mph10 to 11 km/h. 11% chance of drizzle throughout the day. NightPartly cloudy, with a low around 74°F24°C. Breezy from the S at 6 to 7 mph10 to 11 km/h. 15% chance of showers throughout the night.
	SaturdaySep 12	91°F33°C	71°F22°C	0.08 in2 mm· 16%	40%	Drizzle	S 7 mph11 km/h
DayPartly cloudy and hot, with a high of 91°F33°C and morning low of 71°F22°C. Breezy from the SSW at 7 to 8 mph11 to 12 km/h. 12% chance of drizzle throughout the day. NightPartly cloudy, with a low around 73°F23°C. Breezy from the S at 7 mph11 km/h. 16% chance of drizzle throughout the night.
	SundaySep 13	91°F33°C	71°F22°C	0.11 in2.8 mm· 15%	42%	Showers	S 7 mph12 km/h
DayPartly cloudy and hot, with a high of 91°F33°C and morning low of 71°F22°C. Breezy from the SSW at 8 to 9 mph12 to 14 km/h. 10% chance of drizzle throughout the day. NightPartly cloudy, with a low around 73°F23°C. Breezy from the S at 7 to 8 mph12 to 13 km/h. 15% chance of showers throughout the night.
	MondaySep 14	88°F31°C	71°F22°C	0.13 in3.2 mm· 15%	47%	Showers	S 7 mph12 km/h
DayPartly cloudy and hot, with a high of 88°F31°C and morning low of 71°F22°C. Breezy from the SSW at 7 to 8 mph12 to 13 km/h. 15% chance of showers throughout the day. NightPartly cloudy, with a low around 73°F23°C. Breezy from the S at 7 to 8 mph12 to 13 km/h. 12% chance of showers throughout the night.
	TuesdaySep 15	87°F31°C	70°F21°C	0.09 in2.3 mm· 14%	46%	Drizzle	S 7 mph11 km/h
DayMostly cloudy and hot, with a high of 87°F31°C and morning low of 70°F21°C. Breezy from the SSW at 7 mph10 km/h. 14% chance of drizzle throughout the day. NightPartly cloudy, with a low around 72°F22°C. Breezy from the SSE at 7 mph11 km/h. 13% chance of drizzle throughout the night.
	WednesdaySep 16	85°F29°C	67°F20°C	0.12 in3 mm· 15%	46%	Showers	S 6 mph10 km/h
DayPartly cloudy and warm, with a high of 85°F29°C and morning low of 67°F20°C. Breezy from the SW at 7 mph10 km/h. 15% chance of showers throughout the day. NightPartly cloudy, with a low around 70°F21°C. Breezy from the SE at 6 to 7 mph10 to 11 km/h. 15% 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

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