Current Conditions

Mount Vernon, Illinois

64°F18°C

Cloudy

Wind

NNE 7 mph12 km/h

Humidity

76%

Cloud Cover

93%

As of Wednesday, September 23, 2026 at 11:17 PM CDT

Today's Outlook

Night

Overcast, with a low around 62°F17°C. Light wind from the NNE around 5 mph8 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Cloudy	High 72°F22°C	Low 62°F17°C	Precip 0.01 in0.3 mm6%	Cloud 94%	Wind NNE 5 mph9 km/h	Thursday: Overcast and warm, with a high of 72°F22°C and morning low of 62°F17°C. Light wind from the NNE around 5 mph9 km/h. Thursday Night: Overcast, with a low around 62°F17°C. Light wind from the NNE around 5 mph8 km/h.
Partly Cloudy	High 76°F24°C	Low 62°F17°C	Precip 0 in0 mm—	Cloud 74%	Wind NE 5 mph8 km/h	Friday: Mostly cloudy and warm, with a high of 76°F24°C and morning low of 62°F17°C. Light wind from the NE around 5 mph8 km/h. Friday Night: Mostly cloudy, with a low around 64°F18°C. Light wind from the NE around 5 mph8 km/h.
Drizzle	High 73°F23°C	Low 61°F16°C	Precip 0.02 in0.5 mm16%	Cloud 86%	Wind ENE 4 mph7 km/h	Saturday: Overcast and warm, with a high of 73°F23°C and morning low of 61°F16°C. Light wind from the ENE around 4 mph6 km/h. 16% chance of drizzle in the afternoon. Dry air. Saturday Night: Overcast, with a low around 62°F17°C. Light wind from the NE around 5 mph8 km/h. 14% chance of drizzle overnight.
Drizzle	High 78°F25°C	Low 59°F15°C	Precip 0.01 in0.3 mm13%	Cloud 56%	Wind NE 4 mph7 km/h	Sunday: Mostly cloudy and warm, with a high of 78°F25°C and morning low of 59°F15°C. Light wind from the NE around 4 mph6 km/h. Dry air. Sunday Night: Mostly cloudy, with a low around 62°F16°C. Light wind from the NE around 4 mph7 km/h. 13% chance of drizzle overnight.
Clear	High 81°F27°C	Low 55°F13°C	Precip 0 in0 mm—	Cloud 13%	Wind ENE 4 mph7 km/h	Monday: Mostly clear and warm, with a high of 81°F27°C and morning low of 55°F13°C. Light wind from the NE around 4 mph6 km/h. Dry air. Monday Night: Mostly clear, with a low around 58°F14°C. Light wind from the ENE around 5 mph7 km/h.
Drizzle	High 83°F28°C	Low 55°F13°C	Precip 0.02 in0.4 mm13%	Cloud 60%	Wind SSE 5 mph9 km/h	Tuesday: Mostly cloudy and warm, with a high of 83°F28°C and morning low of 55°F13°C. Light wind from the SSE around 5 mph9 km/h. Dry air. Tuesday Night: Mostly cloudy, with a low around 58°F14°C. Breezy from the SE at 5 to 7 mph9 to 11 km/h. 13% chance of drizzle in the evening.
Light Rain	High 78°F26°C	Low 67°F19°C	Precip 0.38 in9.6 mm41%	Cloud 84%	Wind S 7 mph12 km/h	Wednesday: Overcast and warm, with a high of 78°F26°C and morning low of 67°F19°C. Breezy from the SSW at 8 mph12 km/h. 41% chance of light rain throughout the day. Wednesday Night: Overcast, with a low around 68°F20°C. Breezy from the S at 7 mph11 km/h. 35% chance of light rain throughout the night.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	ThursdaySep 24	72°F22°C	62°F17°C	0.01 in0.3 mm· 6%	94%	Cloudy	NNE 5 mph9 km/h
DayOvercast and warm, with a high of 72°F22°C and morning low of 62°F17°C. Light wind from the NNE around 5 mph9 km/h. NightOvercast, with a low around 62°F17°C. Light wind from the NNE around 5 mph8 km/h.
	FridaySep 25	76°F24°C	62°F17°C	0 in0 mm· —	74%	Partly Cloudy	NE 5 mph8 km/h
DayMostly cloudy and warm, with a high of 76°F24°C and morning low of 62°F17°C. Light wind from the NE around 5 mph8 km/h. NightMostly cloudy, with a low around 64°F18°C. Light wind from the NE around 5 mph8 km/h.
	SaturdaySep 26	73°F23°C	61°F16°C	0.02 in0.5 mm· 16%	86%	Drizzle	ENE 4 mph7 km/h
DayOvercast and warm, with a high of 73°F23°C and morning low of 61°F16°C. Light wind from the ENE around 4 mph6 km/h. 16% chance of drizzle in the afternoon. Dry air. NightOvercast, with a low around 62°F17°C. Light wind from the NE around 5 mph8 km/h. 14% chance of drizzle overnight.
	SundaySep 27	78°F25°C	59°F15°C	0.01 in0.3 mm· 13%	56%	Drizzle	NE 4 mph7 km/h
DayMostly cloudy and warm, with a high of 78°F25°C and morning low of 59°F15°C. Light wind from the NE around 4 mph6 km/h. Dry air. NightMostly cloudy, with a low around 62°F16°C. Light wind from the NE around 4 mph7 km/h. 13% chance of drizzle overnight.
	MondaySep 28	81°F27°C	55°F13°C	0 in0 mm· —	13%	Clear	ENE 4 mph7 km/h
DayMostly clear and warm, with a high of 81°F27°C and morning low of 55°F13°C. Light wind from the NE around 4 mph6 km/h. Dry air. NightMostly clear, with a low around 58°F14°C. Light wind from the ENE around 5 mph7 km/h.
	TuesdaySep 29	83°F28°C	55°F13°C	0.02 in0.4 mm· 13%	60%	Drizzle	SSE 5 mph9 km/h
DayMostly cloudy and warm, with a high of 83°F28°C and morning low of 55°F13°C. Light wind from the SSE around 5 mph9 km/h. Dry air. NightMostly cloudy, with a low around 58°F14°C. Breezy from the SE at 5 to 7 mph9 to 11 km/h. 13% chance of drizzle in the evening.
	WednesdaySep 30	78°F26°C	67°F19°C	0.38 in9.6 mm· 41%	84%	Light Rain	S 7 mph12 km/h
DayOvercast and warm, with a high of 78°F26°C and morning low of 67°F19°C. Breezy from the SSW at 8 mph12 km/h. 41% chance of light rain throughout the day. NightOvercast, with a low around 68°F20°C. Breezy from the S at 7 mph11 km/h. 35% chance of light rain throughout the night.
	ThursdayOct 1	77°F25°C	65°F18°C	0.42 in10.7 mm· 37%	73%	Light Rain	S 7 mph12 km/h
DayMostly cloudy and warm, with a high of 77°F25°C and morning low of 65°F18°C. Breezy from the SSW at 8 to 9 mph13 to 14 km/h. 37% chance of light rain throughout the day. NightMostly cloudy, with a low around 66°F19°C. Breezy from the S at 7 mph11 km/h. 35% chance of light rain throughout the night.
	FridayOct 2	77°F25°C	63°F17°C	0.26 in6.6 mm· 28%	59%	Showers	SW 7 mph12 km/h
DayMostly cloudy and warm, with a high of 77°F25°C and morning low of 63°F17°C. Breezy from the SW at 8 to 9 mph13 to 14 km/h. 28% chance of showers throughout the day. NightMostly cloudy, with a low around 65°F18°C. Breezy from the SW at 7 mph11 km/h. 27% chance of showers throughout the night.
	SaturdayOct 3	77°F25°C	61°F16°C	0.15 in3.9 mm· 20%	50%	Showers	SW 7 mph11 km/h
DayMostly cloudy and warm, with a high of 77°F25°C and morning low of 61°F16°C. Breezy from the WSW at 7 to 8 mph11 to 12 km/h. 16% chance of drizzle throughout the day. NightPartly cloudy, with a low around 63°F17°C. Breezy from the SW at 6 to 7 mph10 to 11 km/h. 20% chance of showers throughout the night.
	SundayOct 4	74°F23°C	59°F15°C	0.15 in3.8 mm· 19%	48%	Showers	WNW 8 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 15 km/h. 19% chance of showers throughout the day. NightPartly cloudy, with a low around 61°F16°C. Breezy from the WNW at 7 mph12 km/h. 16% chance of showers throughout the night.
	MondayOct 5	71°F21°C	53°F12°C	0.14 in3.6 mm· 15%	42%	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 to 8 mph12 to 13 km/h. 15% chance of showers throughout the day. Dry air. NightPartly cloudy, with a low around 56°F13°C. Breezy from the WNW at 7 mph11 km/h. 13% chance of showers throughout the night.
	TuesdayOct 6	71°F22°C	53°F11°C	0.08 in2.1 mm· 10%	36%	Drizzle	W 7 mph11 km/h
DayPartly cloudy and warm, with a high of 71°F22°C and morning low of 53°F11°C. Breezy from the WNW at 7 to 8 mph12 to 13 km/h. Dry air. NightPartly cloudy, with a low around 55°F13°C. Breezy from the W at 7 mph11 km/h. 10% chance of drizzle throughout the night.
	WednesdayOct 7	71°F22°C	52°F11°C	0.07 in1.7 mm· 11%	32%	Drizzle	NW 7 mph11 km/h
DayPartly cloudy and warm, with a high of 71°F22°C and morning low of 52°F11°C. Breezy from the NW at 7 to 8 mph12 to 13 km/h. Dry air. NightPartly cloudy, with a low around 54°F12°C. Breezy from the NW at 7 mph11 km/h. 11% chance of drizzle throughout the night.
	ThursdayOct 8	71°F22°C	50°F10°C	0.05 in1.2 mm· 9%	29%	Clear	NW 7 mph11 km/h
DayPartly cloudy and warm, with a high of 71°F22°C and morning low of 50°F10°C. Breezy from the NW at 7 to 8 mph11 to 13 km/h. Dry air. NightPartly cloudy, with a low around 53°F11°C. Light wind from the NNW around 6 mph10 km/h.

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

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.

WeatherMesh consistently outperforms legacy models in independent benchmarks. View Benchmarks →

Access WeatherMesh forecasts programmatically via our API. API Documentation →

How to Access Weather Forecasts

Pattern	Example	Description
/weather/{country}/{city}/	/weather/united-states/san-francisco/	City forecast (canonical URL)
/weather/{city}/	/weather/tokyo/	Shorthand — redirects to most populous match
/weather/{country}/{region}/{city}/	/weather/united-states/california/san-francisco/	With region — redirects to canonical
/weather/nearby?lat={lat}&lon={lon}	/weather/nearby?lat=48.1&lon=11.5	Find nearest city by coordinates
/weather/{country}/	/weather/germany/	Country index — all cities by region

Country and city names use lowercase slugs with hyphens (e.g. united-states, san-francisco). Arbitrary city names are supported — if not in our database, we geocode the name and serve the forecast for that location.

For programmatic access, use theWindBorne Forecast APIwhich returns structured JSON for any coordinates worldwide.

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