Current Conditions

Mount Vernon, Illinois

90°F32°C

Partly Cloudy

Wind

SE 3 mph6 km/h

Humidity

41%

Cloud Cover

71%

As of Tuesday, September 8, 2026 at 7:00 PM CDT

Today's Outlook

Night

Mostly cloudy, with a low around 81°F27°C. Light wind from the SSE around 4 mph7 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Partly Cloudy	High 94°F35°C	Low 81°F27°C	Precip 0 in0 mm—	Cloud 76%	Wind SSE 4 mph6 km/h	Tuesday: Overcast and hot, with a high of 94°F35°C and morning low of 90°F32°C. Light wind from the S around 3 mph5 km/h. Tuesday Night: Mostly cloudy, with a low around 81°F27°C. Light wind from the SSE around 4 mph7 km/h.
Drizzle	High 95°F35°CFeels 100°F38°C	Low 77°F25°C	Precip 0.03 in0.8 mm26%	Cloud 43%	Wind SW 7 mph11 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 SW at 8 to 10 mph13 to 15 km/h. 16% chance of drizzle in the afternoon. Heat risk in the afternoon. Wednesday Night: Partly cloudy, with a low around 77°F25°C. Breezy from the S at 5 to 7 mph9 to 12 km/h. 26% chance of drizzle in the evening.
Light Rain	High 83°F28°CFeels 87°F31°C	Low 75°F24°C	Precip 0.24 in6.2 mm68%	Cloud 82%	Wind NNW 4 mph7 km/h	Thursday: Overcast and warm, with a high of 83°F28°C and morning low of 75°F24°C. Light wind from the NW around 4 mph7 km/h. 68% chance of light rain throughout the day. Heavy, humid air. Thursday Night: Mostly cloudy, with a low around 76°F24°C. Light wind from the NNE around 4 mph7 km/h. 55% chance of light rain throughout the night.
Light Rain	High 85°F29°CFeels 88°F31°C	Low 71°F22°C	Precip 0.2 in5.1 mm35%	Cloud 72%	Wind E 4 mph6 km/h	Friday: Overcast and warm, with a high of 85°F29°C and morning low of 71°F22°C. Light wind from the ESE around 4 mph6 km/h. 35% chance of light rain throughout the day. Humid. Friday Night: Mostly cloudy, with a low around 72°F22°C. Light wind from the E around 4 mph7 km/h. 27% chance of showers throughout the night.
Drizzle	High 91°F33°C	Low 71°F22°C	Precip 0.05 in1.2 mm14%	Cloud 42%	Wind SW 4 mph7 km/h	Saturday: Mostly cloudy and hot, with a high of 91°F33°C and morning low of 71°F22°C. Light wind from the SW around 5 mph8 km/h. 14% chance of drizzle around midday. Humid. Saturday Night: Partly cloudy, with a low around 72°F22°C. Light wind from the S around 4 mph7 km/h. 13% chance of drizzle throughout the night.
Clear	High 90°F32°C	Low 71°F22°C	Precip 0.01 in0.3 mm9%	Cloud 23%	Wind N 6 mph9 km/h	Sunday: Partly cloudy and hot, with a high of 90°F32°C and morning low of 71°F22°C. Light wind from the NNW around 6 mph9 km/h. Sunday Night: Mostly clear, with a low around 73°F23°C. Light wind from the N around 5 mph9 km/h.
Clear	High 91°F33°C	Low 68°F20°C	Precip 0.02 in0.4 mm4%	Cloud 27%	Wind SE 7 mph11 km/h	Monday: Partly cloudy and hot, with a high of 91°F33°C and morning low of 68°F20°C. Breezy from the SE at 7 to 8 mph11 to 13 km/h. Monday Night: Mostly clear, with a low around 70°F21°C. Breezy from the SE at 7 to 8 mph12 to 14 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	TuesdaySep 8	94°F35°C	81°F27°C	0 in0 mm· —	76%	Partly Cloudy	SSE 4 mph6 km/h
DayOvercast and hot, with a high of 94°F35°C and morning low of 90°F32°C. Light wind from the S around 3 mph5 km/h. NightMostly cloudy, with a low around 81°F27°C. Light wind from the SSE around 4 mph7 km/h.
	WednesdaySep 9	95°F35°C Feels 100°F38°C	77°F25°C	0.03 in0.8 mm· 26%	43%	Drizzle	SW 7 mph11 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 SW at 8 to 10 mph13 to 15 km/h. 16% chance of drizzle in the afternoon. Heat risk in the afternoon. NightPartly cloudy, with a low around 77°F25°C. Breezy from the S at 5 to 7 mph9 to 12 km/h. 26% chance of drizzle in the evening.
	ThursdaySep 10	83°F28°C Feels 87°F31°C	75°F24°C	0.24 in6.2 mm· 68%	82%	Light Rain	NNW 4 mph7 km/h
DayOvercast and warm, with a high of 83°F28°C and morning low of 75°F24°C. Light wind from the NW around 4 mph7 km/h. 68% chance of light rain throughout the day. Heavy, humid air. NightMostly cloudy, with a low around 76°F24°C. Light wind from the NNE around 4 mph7 km/h. 55% chance of light rain throughout the night.
	FridaySep 11	85°F29°C Feels 88°F31°C	71°F22°C	0.2 in5.1 mm· 35%	72%	Light Rain	E 4 mph6 km/h
DayOvercast and warm, with a high of 85°F29°C and morning low of 71°F22°C. Light wind from the ESE around 4 mph6 km/h. 35% chance of light rain throughout the day. Humid. NightMostly cloudy, with a low around 72°F22°C. Light wind from the E around 4 mph7 km/h. 27% chance of showers throughout the night.
	SaturdaySep 12	91°F33°C	71°F22°C	0.05 in1.2 mm· 14%	42%	Drizzle	SW 4 mph7 km/h
DayMostly cloudy and hot, with a high of 91°F33°C and morning low of 71°F22°C. Light wind from the SW around 5 mph8 km/h. 14% chance of drizzle around midday. Humid. NightPartly cloudy, with a low around 72°F22°C. Light wind from the S around 4 mph7 km/h. 13% chance of drizzle throughout the night.
	SundaySep 13	90°F32°C	71°F22°C	0.01 in0.3 mm· 9%	23%	Clear	N 6 mph9 km/h
DayPartly cloudy and hot, with a high of 90°F32°C and morning low of 71°F22°C. Light wind from the NNW around 6 mph9 km/h. NightMostly clear, with a low around 73°F23°C. Light wind from the N around 5 mph9 km/h.
	MondaySep 14	91°F33°C	68°F20°C	0.02 in0.4 mm· 4%	27%	Clear	SE 7 mph11 km/h
DayPartly cloudy and hot, with a high of 91°F33°C and morning low of 68°F20°C. Breezy from the SE at 7 to 8 mph11 to 13 km/h. NightMostly clear, with a low around 70°F21°C. Breezy from the SE at 7 to 8 mph12 to 14 km/h.
	TuesdaySep 15	94°F34°C	73°F23°C	0.03 in0.7 mm· 13%	29%	Drizzle	SSW 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 mph14 to 15 km/h. 10% chance of drizzle in the afternoon. NightPartly cloudy, with a low around 75°F24°C. Breezy from the S at 7 to 8 mph12 to 13 km/h. 13% chance of drizzle in the evening.
	WednesdaySep 16	93°F34°C	74°F23°C	0.04 in1.1 mm· 14%	42%	Drizzle	S 6 mph10 km/h
DayPartly cloudy and hot, with a high of 93°F34°C and morning low of 74°F23°C. Light wind from the SSW around 6 mph10 km/h. 14% chance of drizzle throughout the day. Heat risk in the afternoon. NightPartly cloudy, with a low around 76°F25°C. Light wind from the SSE around 6 mph10 km/h.
	ThursdaySep 17	93°F34°C	75°F24°C	0.05 in1.3 mm· 12%	30%	Drizzle	SSW 7 mph12 km/h
DayPartly cloudy and hot, with a high of 93°F34°C and morning low of 75°F24°C. Breezy from the SSW at 8 mph12 km/h. 12% chance of drizzle in the morning. Humid. NightPartly cloudy, with a low around 77°F25°C. Breezy from the S at 7 to 8 mph11 to 12 km/h. 11% chance of drizzle in the evening.
	FridaySep 18	88°F31°C	73°F23°C	0.1 in2.5 mm· 15%	36%	Showers	SW 8 mph12 km/h
DayPartly cloudy and hot, with a high of 88°F31°C and morning low of 73°F23°C. Breezy from the SW at 8 mph13 km/h. 15% chance of drizzle throughout the day. NightPartly cloudy, with a low around 75°F24°C. Breezy from the SSW at 7 to 8 mph12 to 12 km/h. 13% chance of showers throughout the night.
	SaturdaySep 19	82°F28°C	67°F19°C	0.14 in3.6 mm· 22%	48%	Showers	NW 7 mph12 km/h
DayMostly cloudy and warm, with a high of 82°F28°C and morning low of 67°F19°C. Breezy from the NW at 7 to 8 mph12 to 13 km/h. 21% chance of showers throughout the day. NightPartly cloudy, with a low around 69°F21°C. Breezy from the NNW at 7 mph11 km/h. 22% chance of showers throughout the night.
	SundaySep 20	78°F26°C	62°F17°C	0.13 in3.3 mm· 18%	55%	Showers	N 7 mph11 km/h
DayMostly cloudy and warm, with a high of 78°F26°C and morning low of 62°F17°C. Breezy from the N at 7 to 8 mph11 to 12 km/h. 18% chance of showers throughout the day. NightMostly cloudy, with a low around 65°F18°C. Breezy from the NNE at 7 mph11 km/h. 13% chance of drizzle throughout the night.
	MondaySep 21	76°F25°C	59°F15°C	0.1 in2.5 mm· 14%	55%	Drizzle	NE 7 mph11 km/h
DayMostly cloudy and warm, with a high of 76°F25°C and morning low of 59°F15°C. Breezy from the NE at 7 to 8 mph11 to 12 km/h. 14% chance of drizzle throughout the day. NightMostly cloudy, with a low around 62°F16°C. Breezy from the NE at 7 mph11 km/h. 12% chance of drizzle throughout the night.
	TuesdaySep 22	76°F25°C	58°F15°C	0.09 in2.3 mm· 11%	57%	Drizzle	NE 6 mph10 km/h
DayMostly cloudy and warm, with a high of 76°F25°C and morning low of 58°F15°C. Breezy from the NE at 7 mph11 km/h. 11% chance of drizzle throughout the day. NightMostly cloudy, with a low around 60°F16°C. Breezy from the ENE at 6 to 7 mph10 to 11 km/h. 10% 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