Current Conditions

Collinsville, Illinois

83°F28°C

Drizzle

Wind

SSE 7 mph11 km/h

Humidity

48%

Cloud Cover

51%

As of Tuesday, September 8, 2026 at 11:21 PM CDT

Today's Outlook

Night

Partly cloudy, with a low around 77°F25°C. Breezy from the S at 6 to 7 mph9 to 12 km/h. 37% chance of drizzle in the evening.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Drizzle	High 94°F35°CFeels 100°F38°C	Low 76°F25°C	Precip 0.04 in0.9 mm37%	Cloud 41%	Wind SW 6 mph9 km/h	Wednesday: Partly cloudy and hot, with a high of 94°F35°C and morning low of 76°F25°C — feels like 100°F38°C. Breezy from the WSW at 6 to 7 mph9 to 12 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 S at 6 to 7 mph9 to 12 km/h. 37% chance of drizzle in the evening.
Rain	High 80°F27°C	Low 73°F23°C	Precip 0.52 in13.3 mm90%	Cloud 91%	Wind NNW 4 mph6 km/h	Thursday: Overcast and warm, with a high of 80°F27°C and morning low of 73°F23°C. Light wind from the WNW around 4 mph7 km/h. 90% chance of rain throughout the day. Heavy, humid air. Thursday Night: Overcast, with a low around 73°F23°C. Light wind from the NNE around 4 mph6 km/h. 81% chance of rain throughout the night.
Showers	High 84°F29°CFeels 87°F30°C	Low 69°F21°C	Precip 0.15 in3.9 mm34%	Cloud 58%	Wind E 4 mph6 km/h	Friday: Mostly cloudy and warm, with a high of 84°F29°C and morning low of 69°F21°C. Light wind from the ESE around 4 mph6 km/h. 34% chance of showers 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. 22% chance of showers throughout the night.
Drizzle	High 89°F32°CFeels 92°F33°C	Low 70°F21°C	Precip 0.03 in0.8 mm15%	Cloud 47%	Wind SW 4 mph7 km/h	Saturday: Mostly cloudy and hot, with a high of 89°F32°C and morning low of 70°F21°C. Light wind from the SW around 5 mph8 km/h. 15% chance of drizzle around midday. Humid. Saturday Night: Partly cloudy, with a low around 71°F21°C. Light wind from the S around 4 mph7 km/h.
Clear	High 89°F32°C	Low 70°F21°C	Precip 0.02 in0.5 mm5%	Cloud 28%	Wind NNE 5 mph8 km/h	Sunday: Partly cloudy and hot, with a high of 89°F32°C and morning low of 70°F21°C. Light wind from the N around 5 mph8 km/h. Humid. Sunday Night: Mostly clear, with a low around 72°F22°C. Light wind from the NE around 5 mph8 km/h.
Clear	High 94°F34°C	Low 70°F21°C	Precip 0.02 in0.4 mm4%	Cloud 22%	Wind SSE 8 mph13 km/h	Monday: Partly cloudy and hot, with a high of 94°F34°C and morning low of 70°F21°C. Breezy from the SSE at 8 to 10 mph13 to 16 km/h. Monday Night: Mostly clear, with a low around 72°F22°C. Breezy from the SSE at 8 to 10 mph13 to 16 km/h.
Drizzle	High 94°F34°C	Low 75°F24°C	Precip 0.04 in1.1 mm14%	Cloud 31%	Wind SSW 8 mph13 km/h	Tuesday: Partly cloudy and hot, with a high of 94°F34°C and morning low of 75°F24°C. Breezy from the SSW at 8 mph13 km/h. 13% chance of drizzle around midday. Heat risk in the afternoon. Tuesday Night: Partly cloudy, with a low around 77°F25°C. Breezy from the S at 8 to 9 mph12 to 15 km/h. 14% chance of drizzle in the evening.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 9	94°F35°C Feels 100°F38°C	76°F25°C	0.04 in0.9 mm· 37%	41%	Drizzle	SW 6 mph9 km/h
DayPartly cloudy and hot, with a high of 94°F35°C and morning low of 76°F25°C — feels like 100°F38°C. Breezy from the WSW at 6 to 7 mph9 to 12 km/h. 10% chance of drizzle. Heat risk in the afternoon. NightPartly cloudy, with a low around 77°F25°C. Breezy from the S at 6 to 7 mph9 to 12 km/h. 37% chance of drizzle in the evening.
	ThursdaySep 10	80°F27°C	73°F23°C	0.52 in13.3 mm· 90%	91%	Rain	NNW 4 mph6 km/h
DayOvercast and warm, with a high of 80°F27°C and morning low of 73°F23°C. Light wind from the WNW around 4 mph7 km/h. 90% chance of rain throughout the day. Heavy, humid air. NightOvercast, with a low around 73°F23°C. Light wind from the NNE around 4 mph6 km/h. 81% chance of rain throughout the night.
	FridaySep 11	84°F29°C Feels 87°F30°C	69°F21°C	0.15 in3.9 mm· 34%	58%	Showers	E 4 mph6 km/h
DayMostly cloudy and warm, with a high of 84°F29°C and morning low of 69°F21°C. Light wind from the ESE around 4 mph6 km/h. 34% chance of showers throughout the day. Humid. NightPartly cloudy, with a low around 70°F21°C. Light wind from the E around 4 mph6 km/h. 22% chance of showers throughout the night.
	SaturdaySep 12	89°F32°C Feels 92°F33°C	70°F21°C	0.03 in0.8 mm· 15%	47%	Drizzle	SW 4 mph7 km/h
DayMostly cloudy and hot, with a high of 89°F32°C and morning low of 70°F21°C. Light wind from the SW around 5 mph8 km/h. 15% chance of drizzle around midday. Humid. NightPartly cloudy, with a low around 71°F21°C. Light wind from the S around 4 mph7 km/h.
	SundaySep 13	89°F32°C	70°F21°C	0.02 in0.5 mm· 5%	28%	Clear	NNE 5 mph8 km/h
DayPartly cloudy and hot, with a high of 89°F32°C and morning low of 70°F21°C. Light wind from the N around 5 mph8 km/h. Humid. NightMostly clear, with a low around 72°F22°C. Light wind from the NE around 5 mph8 km/h.
	MondaySep 14	94°F34°C	70°F21°C	0.02 in0.4 mm· 4%	22%	Clear	SSE 8 mph13 km/h
DayPartly cloudy and hot, with a high of 94°F34°C and morning low of 70°F21°C. Breezy from the SSE at 8 to 10 mph13 to 16 km/h. NightMostly clear, with a low around 72°F22°C. Breezy from the SSE at 8 to 10 mph13 to 16 km/h.
	TuesdaySep 15	94°F34°C	75°F24°C	0.04 in1.1 mm· 14%	31%	Drizzle	SSW 8 mph13 km/h
DayPartly cloudy and hot, with a high of 94°F34°C and morning low of 75°F24°C. Breezy from the SSW at 8 mph13 km/h. 13% chance of drizzle around midday. Heat risk in the afternoon. NightPartly cloudy, with a low around 77°F25°C. Breezy from the S at 8 to 9 mph12 to 15 km/h. 14% chance of drizzle in the evening.
	WednesdaySep 16	90°F32°C Feels 94°F34°C	74°F23°C	0.1 in2.6 mm· 23%	50%	Showers	SSE 6 mph10 km/h
DayMostly cloudy and hot, with a high of 90°F32°C and morning low of 74°F23°C. Light wind from the S around 6 mph9 km/h. 22% chance of showers throughout the day. Humid. NightPartly cloudy, with a low around 76°F24°C. Breezy from the SSE at 7 to 8 mph10 to 12 km/h. 23% chance of showers throughout the night.
	ThursdaySep 17	90°F32°C	74°F23°C	0.1 in2.6 mm· 24%	41%	Drizzle	SSW 8 mph12 km/h
DayPartly cloudy and hot, with a high of 90°F32°C and morning low of 74°F23°C. Breezy from the SSW at 8 to 9 mph13 to 14 km/h. 15% chance of drizzle throughout the day. Humid. NightPartly cloudy, with a low around 76°F24°C. Breezy from the S at 7 to 8 mph12 to 12 km/h. 24% chance of drizzle throughout the night.
	FridaySep 18	81°F27°C	68°F20°C	0.16 in4.1 mm· 26%	51%	Showers	NW 7 mph12 km/h
DayMostly cloudy and warm, with a high of 81°F27°C and morning low of 68°F20°C. Breezy from the NW at 7 to 8 mph12 to 12 km/h. 24% chance of showers throughout the day. NightPartly cloudy, with a low around 71°F21°C. Breezy from the NNW at 7 to 8 mph11 to 12 km/h. 26% chance of showers throughout the night.
	SaturdaySep 19	78°F26°C	63°F17°C	0.13 in3.3 mm· 20%	50%	Showers	N 6 mph10 km/h
DayMostly cloudy and warm, with a high of 78°F26°C and morning low of 63°F17°C. Breezy from the NNW at 6 to 7 mph10 to 12 km/h. 20% chance of drizzle throughout the day. NightPartly cloudy, with a low around 65°F18°C. Light wind from the N around 6 mph10 km/h. 17% chance of showers throughout the night.
	SundaySep 20	75°F24°C	59°F15°C	0.11 in2.9 mm· 18%	51%	Drizzle	NNE 7 mph11 km/h
DayMostly cloudy and warm, with a high of 75°F24°C and morning low of 59°F15°C. Breezy from the NNE at 7 mph11 km/h. 18% chance of drizzle throughout the day. NightPartly cloudy, with a low around 62°F16°C. Light wind from the NNE around 6 mph10 km/h. 14% chance of drizzle throughout the night.
	MondaySep 21	75°F24°C	58°F14°C	0.1 in2.6 mm· 14%	54%	Drizzle	NE 6 mph10 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 6 to 7 mph10 to 11 km/h. 14% chance of drizzle throughout the day. NightMostly cloudy, with a low around 60°F15°C. Light wind from the NE around 6 mph10 km/h. 14% chance of drizzle throughout the night.
	TuesdaySep 22	75°F24°C	58°F14°C	0.15 in3.7 mm· 22%	55%	Showers	ENE 6 mph10 km/h
DayMostly cloudy and warm, with a high of 75°F24°C and morning low of 58°F14°C. Breezy from the ENE at 7 mph11 km/h. 22% chance of showers throughout the day. NightMostly cloudy, with a low around 60°F15°C. Light wind from the ENE around 6 mph10 km/h. 20% chance of showers throughout the night.
	WednesdaySep 23	76°F24°C	58°F15°C	0.11 in2.9 mm· 19%	57%	Showers	E 7 mph11 km/h
DayMostly cloudy and warm, with a high of 76°F24°C and morning low of 58°F15°C. Breezy from the E at 7 mph11 km/h. 19% chance of showers throughout the day. NightMostly cloudy, with a low around 60°F16°C. Light wind from the E around 6 mph10 km/h. 17% chance of drizzle throughout the night.

Nearby Cities

Fairview Heights6 mi9 km O'Fallon7 mi11 km Granite City9 mi15 km East Saint Louis10 mi15 km Edwardsville10 mi16 km Belleville10 mi17 km

About This Forecast

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Coordinates: 38.6703°N, 89.9845°W·Elevation: 171m·Timezone: America/Chicago·Population: 24,754