Current Conditions

Mount Vernon, Illinois

80°F26°C

Hot

Wind

SSW 5 mph8 km/h

Humidity

71%

Cloud Cover

As of Thursday, September 3, 2026 at 3:24 AM CDT

Today's Outlook

Day

Mostly clear and hot, with a high of 100°F38°C and morning low of 78°F25°C. Breezy from the SW at 6 to 7 mph10 to 11 km/h. Heat risk in the afternoon.

Night

Mostly clear, with a low around 80°F26°C. Light wind from the SSW around 5 mph8 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Hot	High 100°F38°C	Low 78°F25°C	Precip 0 in0 mm—	Cloud 11%	Wind SSW 6 mph9 km/h	Thursday: Mostly clear and hot, with a high of 100°F38°C and morning low of 78°F25°C. Breezy from the SW at 6 to 7 mph10 to 11 km/h. Heat risk in the afternoon. Thursday Night: Mostly clear, with a low around 80°F26°C. Light wind from the SSW around 5 mph8 km/h.
Hot	High 100°F38°C	Low 78°F25°C	Precip 0 in0 mm—	Cloud 10%	Wind SW 4 mph7 km/h	Friday: Mostly clear and hot, with a high of 100°F38°C and morning low of 78°F25°C. Light wind from the WSW around 4 mph7 km/h. Heat risk in the afternoon. Friday Night: Mostly clear, with a low around 80°F27°C. Light wind from the SSW around 4 mph7 km/h.
Drizzle	High 100°F38°C	Low 79°F26°C	Precip 0.04 in0.9 mm42%	Cloud 31%	Wind NW 5 mph8 km/h	Saturday: Partly cloudy and hot, with a high of 100°F38°C and morning low of 79°F26°C. Light wind from the NW around 5 mph7 km/h. 32% chance of drizzle in the afternoon. Heat risk in the afternoon. Saturday Night: Partly cloudy, with a low around 81°F27°C. Light wind from the NNW around 5 mph8 km/h. 42% chance of drizzle in the evening.
Clear	High 92°F33°C	Low 75°F24°C	Precip 0.02 in0.4 mm4%	Cloud 31%	Wind NE 8 mph12 km/h	Sunday: Partly cloudy and hot, with a high of 92°F33°C and morning low of 75°F24°C. Breezy from the NE at 8 to 9 mph12 to 14 km/h. Humid. Sunday Night: Partly cloudy, with a low around 78°F25°C. Breezy from the NE at 8 mph12 km/h.
Clear	High 91°F33°C	Low 68°F20°C	Precip 0 in0 mm—	Cloud 27%	Wind ENE 6 mph10 km/h	Monday: Mostly clear and hot, with a high of 91°F33°C and morning low of 68°F20°C. Light wind from the ENE around 6 mph10 km/h. Monday Night: Partly cloudy, with a low around 71°F22°C. Breezy from the ENE at 6 to 8 mph10 to 12 km/h.
Hot	High 96°F36°C	Low 69°F21°C	Precip 0 in0 mm—	Cloud 29%	Wind SSE 6 mph9 km/h	Tuesday: Partly cloudy and hot, with a high of 96°F36°C and morning low of 69°F21°C. Light wind from the S around 5 mph9 km/h. Heat risk in the afternoon. Tuesday Night: Partly cloudy, with a low around 71°F22°C. Breezy from the SE at 6 to 7 mph10 to 12 km/h.
Hot	High 98°F36°CFeels 101°F38°C	Low 77°F25°C	Precip 0 in0 mm—	Cloud 19%	Wind SSW 9 mph14 km/h	Wednesday: Mostly clear and hot, with a high of 98°F36°C and morning low of 77°F25°C. Breezy from the SSW at 9 to 10 mph15 to 15 km/h. Heat risk in the afternoon. Wednesday Night: Mostly clear, with a low around 78°F26°C. Breezy from the SSW at 8 to 10 mph14 to 15 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	ThursdaySep 3	100°F38°C	78°F25°C	0 in0 mm· —	11%	Hot	SSW 6 mph9 km/h
DayMostly clear and hot, with a high of 100°F38°C and morning low of 78°F25°C. Breezy from the SW at 6 to 7 mph10 to 11 km/h. Heat risk in the afternoon. NightMostly clear, with a low around 80°F26°C. Light wind from the SSW around 5 mph8 km/h.
	FridaySep 4	100°F38°C	78°F25°C	0 in0 mm· —	10%	Hot	SW 4 mph7 km/h
DayMostly clear and hot, with a high of 100°F38°C and morning low of 78°F25°C. Light wind from the WSW around 4 mph7 km/h. Heat risk in the afternoon. NightMostly clear, with a low around 80°F27°C. Light wind from the SSW around 4 mph7 km/h.
	SaturdaySep 5	100°F38°C	79°F26°C	0.04 in0.9 mm· 42%	31%	Drizzle	NW 5 mph8 km/h
DayPartly cloudy and hot, with a high of 100°F38°C and morning low of 79°F26°C. Light wind from the NW around 5 mph7 km/h. 32% chance of drizzle in the afternoon. Heat risk in the afternoon. NightPartly cloudy, with a low around 81°F27°C. Light wind from the NNW around 5 mph8 km/h. 42% chance of drizzle in the evening.
	SundaySep 6	92°F33°C	75°F24°C	0.02 in0.4 mm· 4%	31%	Clear	NE 8 mph12 km/h
DayPartly cloudy and hot, with a high of 92°F33°C and morning low of 75°F24°C. Breezy from the NE at 8 to 9 mph12 to 14 km/h. Humid. NightPartly cloudy, with a low around 78°F25°C. Breezy from the NE at 8 mph12 km/h.
	MondaySep 7	91°F33°C	68°F20°C	0 in0 mm· —	27%	Clear	ENE 6 mph10 km/h
DayMostly clear and hot, with a high of 91°F33°C and morning low of 68°F20°C. Light wind from the ENE around 6 mph10 km/h. NightPartly cloudy, with a low around 71°F22°C. Breezy from the ENE at 6 to 8 mph10 to 12 km/h.
	TuesdaySep 8	96°F36°C	69°F21°C	0 in0 mm· —	29%	Hot	SSE 6 mph9 km/h
DayPartly cloudy and hot, with a high of 96°F36°C and morning low of 69°F21°C. Light wind from the S around 5 mph9 km/h. Heat risk in the afternoon. NightPartly cloudy, with a low around 71°F22°C. Breezy from the SE at 6 to 7 mph10 to 12 km/h.
	WednesdaySep 9	98°F36°C Feels 101°F38°C	77°F25°C	0 in0 mm· —	19%	Hot	SSW 9 mph14 km/h
DayMostly clear and hot, with a high of 98°F36°C and morning low of 77°F25°C. Breezy from the SSW at 9 to 10 mph15 to 15 km/h. Heat risk in the afternoon. NightMostly clear, with a low around 78°F26°C. Breezy from the SSW at 8 to 10 mph14 to 15 km/h.
	ThursdaySep 10	94°F34°C Feels 97°F36°C	78°F26°C	0.05 in1.2 mm· 13%	38%	Drizzle	SW 8 mph13 km/h
DayPartly cloudy and hot, with a high of 94°F34°C and morning low of 78°F26°C. Breezy from the SW at 9 mph14 km/h. 13% chance of drizzle throughout the day. Heat risk in the afternoon. NightPartly cloudy, with a low around 81°F27°C. Breezy from the SW at 8 to 10 mph13 to 15 km/h. 13% chance of drizzle throughout the night.
	FridaySep 11	90°F32°C	74°F23°C	0.09 in2.3 mm· 16%	42%	Drizzle	SW 7 mph10 km/h
DayPartly cloudy and hot, with a high of 90°F32°C and morning low of 74°F23°C. Breezy from the WSW at 7 mph11 km/h. 14% chance of drizzle throughout the day. Humid. NightPartly cloudy, with a low around 76°F24°C. Breezy from the SSW at 6 to 7 mph10 to 11 km/h. 16% chance of drizzle throughout the night.
	SaturdaySep 12	89°F32°C	71°F22°C	0.14 in3.5 mm· 19%	49%	Showers	S 7 mph11 km/h
DayMostly cloudy and hot, with a high of 89°F32°C and morning low of 71°F22°C. Breezy from the SSW at 7 to 8 mph11 to 12 km/h. 17% chance of showers throughout the day. NightPartly cloudy, with a low around 73°F23°C. Breezy from the SSE at 6 to 7 mph10 to 11 km/h. 19% chance of showers throughout the night.
	SundaySep 13	90°F32°C	71°F22°C	0.12 in3 mm· 22%	46%	Showers	S 7 mph12 km/h
DayPartly cloudy and hot, with a high of 90°F32°C and morning low of 71°F22°C. Breezy from the SSW at 8 mph12 km/h. 22% chance of showers throughout the day. Humid. NightPartly cloudy, with a low around 73°F23°C. Breezy from the S at 7 to 8 mph11 to 12 km/h. 18% chance of showers throughout the night.
	MondaySep 14	89°F32°C	72°F22°C	0.11 in2.9 mm· 16%	45%	Showers	SSW 8 mph12 km/h
DayPartly cloudy and hot, with a high of 89°F32°C and morning low of 72°F22°C. Breezy from the SSW at 8 mph13 km/h. 16% chance of showers throughout the day. NightPartly cloudy, with a low around 74°F23°C. Breezy from the S at 7 to 8 mph12 to 12 km/h. 13% chance of showers throughout the night.
	TuesdaySep 15	88°F31°C	70°F21°C	0.11 in2.7 mm· 16%	45%	Drizzle	SSW 7 mph11 km/h
DayPartly cloudy and hot, with a high of 88°F31°C and morning low of 70°F21°C. Breezy from the SW at 7 to 8 mph11 to 12 km/h. 16% chance of drizzle throughout the day. NightPartly cloudy, with a low around 72°F22°C. Breezy from the S at 7 mph11 km/h. 14% chance of drizzle throughout the night.
	WednesdaySep 16	86°F30°C	69°F20°C	0.09 in2.3 mm· 17%	46%	Drizzle	SW 7 mph10 km/h
DayPartly cloudy and warm, with a high of 86°F30°C and morning low of 69°F20°C. Breezy from the WSW at 7 mph11 km/h. 17% chance of drizzle throughout the day. NightPartly cloudy, with a low around 71°F21°C. Light wind from the ENE around 6 mph10 km/h. 16% chance of drizzle throughout the night.
	ThursdaySep 17	85°F29°C	66°F19°C	0.09 in2.3 mm· 14%	38%	Drizzle	NE 6 mph10 km/h
DayPartly cloudy and warm, with a high of 85°F29°C and morning low of 66°F19°C. Breezy from the NNE at 7 mph11 km/h. 14% chance of drizzle throughout the day. NightPartly cloudy, with a low around 68°F20°C. Light wind from the ENE around 6 mph10 km/h. 13% chance of drizzle throughout the night.

Nearby Cities

Marion41 mi65 km Carbondale44 mi71 km O'Fallon58 mi93 km Belleville60 mi97 km Fairview Heights62 mi99 km Collinsville63 mi102 km

About This Forecast

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Coordinates: 38.3173°N, 88.9031°W·Elevation: 156m·Timezone: America/Chicago·Population: 15,087