Current Conditions

Decatur, Illinois

61°F16°C

Cloudy

Wind

NE 10 mph16 km/h

Humidity

77%

Cloud Cover

80%

As of Tuesday, September 22, 2026 at 10:18 PM CDT

Today's Outlook

Night

Overcast, with a low around 60°F16°C. Breezy from the NE at 8 to 9 mph13 to 14 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Cloudy	High 67°F19°C	Low 59°F15°C	Precip 0 in0.1 mm1%	Cloud 97%	Wind NE 9 mph14 km/h	Wednesday: Overcast and mild, with a high of 67°F19°C and morning low of 59°F15°C. Breezy from the NE at 10 mph15 km/h. Wednesday Night: Overcast, with a low around 60°F16°C. Breezy from the NE at 8 to 9 mph13 to 14 km/h.
Cloudy	High 70°F21°C	Low 59°F15°C	Precip 0 in0.1 mm—	Cloud 88%	Wind NE 6 mph10 km/h	Thursday: Overcast and warm, with a high of 70°F21°C and morning low of 59°F15°C. Breezy from the NE at 6 to 7 mph10 to 11 km/h. Thursday Night: Overcast, with a low around 59°F15°C. Breezy from the NE at 6 to 7 mph10 to 12 km/h.
Cloudy	High 74°F23°C	Low 60°F16°C	Precip 0.01 in0.2 mm3%	Cloud 83%	Wind ENE 6 mph9 km/h	Friday: Overcast and warm, with a high of 74°F23°C and morning low of 60°F16°C. Light wind from the ENE around 6 mph9 km/h. Friday Night: Overcast, with a low around 61°F16°C. Light wind from the ENE around 5 mph9 km/h.
Drizzle	High 70°F21°C	Low 58°F14°C	Precip 0.03 in0.8 mm21%	Cloud 91%	Wind E 5 mph9 km/h	Saturday: Overcast and warm, with a high of 70°F21°C and morning low of 58°F14°C. Light wind from the ESE around 5 mph8 km/h. 21% chance of drizzle around midday. Dry air. Saturday Night: Overcast, with a low around 60°F16°C. Breezy from the E at 6 to 7 mph9 to 11 km/h. 21% chance of drizzle in the evening.
Drizzle	High 73°F23°C	Low 58°F15°C	Precip 0.04 in1.1 mm24%	Cloud 67%	Wind ENE 5 mph8 km/h	Sunday: Mostly cloudy and warm, with a high of 73°F23°C and morning low of 58°F15°C. Light wind from the E around 5 mph7 km/h. 24% chance of drizzle throughout the day. Dry air. Sunday Night: Mostly cloudy, with a low around 60°F15°C. Light wind from the ENE around 5 mph8 km/h. 17% chance of drizzle overnight.
Clear	High 77°F25°C	Low 55°F13°C	Precip 0 in0.1 mm4%	Cloud 30%	Wind ENE 4 mph7 km/h	Monday: Partly cloudy and warm, with a high of 77°F25°C and morning low of 55°F13°C. Light wind from the ENE around 4 mph7 km/h. Dry air. Monday Night: Partly cloudy, with a low around 57°F14°C. Light wind from the ENE around 5 mph8 km/h.
Light Rain	High 78°F26°C	Low 55°F13°C	Precip 0.11 in2.8 mm27%	Cloud 70%	Wind SE 7 mph11 km/h	Tuesday: Mostly cloudy and warm, with a high of 78°F26°C and morning low of 55°F13°C. Breezy from the SSE at 7 to 8 mph11 to 13 km/h. 14% chance of drizzle around midday. Tuesday Night: Mostly cloudy, with a low around 57°F14°C. Breezy from the SE at 7 to 8 mph11 to 13 km/h. 27% chance of showers in the evening.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 23	67°F19°C	59°F15°C	0 in0.1 mm· 1%	97%	Cloudy	NE 9 mph14 km/h
DayOvercast and mild, with a high of 67°F19°C and morning low of 59°F15°C. Breezy from the NE at 10 mph15 km/h. NightOvercast, with a low around 60°F16°C. Breezy from the NE at 8 to 9 mph13 to 14 km/h.
	ThursdaySep 24	70°F21°C	59°F15°C	0 in0.1 mm· —	88%	Cloudy	NE 6 mph10 km/h
DayOvercast and warm, with a high of 70°F21°C and morning low of 59°F15°C. Breezy from the NE at 6 to 7 mph10 to 11 km/h. NightOvercast, with a low around 59°F15°C. Breezy from the NE at 6 to 7 mph10 to 12 km/h.
	FridaySep 25	74°F23°C	60°F16°C	0.01 in0.2 mm· 3%	83%	Cloudy	ENE 6 mph9 km/h
DayOvercast and warm, with a high of 74°F23°C and morning low of 60°F16°C. Light wind from the ENE around 6 mph9 km/h. NightOvercast, with a low around 61°F16°C. Light wind from the ENE around 5 mph9 km/h.
	SaturdaySep 26	70°F21°C	58°F14°C	0.03 in0.8 mm· 21%	91%	Drizzle	E 5 mph9 km/h
DayOvercast and warm, with a high of 70°F21°C and morning low of 58°F14°C. Light wind from the ESE around 5 mph8 km/h. 21% chance of drizzle around midday. Dry air. NightOvercast, with a low around 60°F16°C. Breezy from the E at 6 to 7 mph9 to 11 km/h. 21% chance of drizzle in the evening.
	SundaySep 27	73°F23°C	58°F15°C	0.04 in1.1 mm· 24%	67%	Drizzle	ENE 5 mph8 km/h
DayMostly cloudy and warm, with a high of 73°F23°C and morning low of 58°F15°C. Light wind from the E around 5 mph7 km/h. 24% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 60°F15°C. Light wind from the ENE around 5 mph8 km/h. 17% chance of drizzle overnight.
	MondaySep 28	77°F25°C	55°F13°C	0 in0.1 mm· 4%	30%	Clear	ENE 4 mph7 km/h
DayPartly cloudy and warm, with a high of 77°F25°C and morning low of 55°F13°C. Light wind from the ENE around 4 mph7 km/h. Dry air. NightPartly cloudy, with a low around 57°F14°C. Light wind from the ENE around 5 mph8 km/h.
	TuesdaySep 29	78°F26°C	55°F13°C	0.11 in2.8 mm· 27%	70%	Light Rain	SE 7 mph11 km/h
DayMostly cloudy and warm, with a high of 78°F26°C and morning low of 55°F13°C. Breezy from the SSE at 7 to 8 mph11 to 13 km/h. 14% chance of drizzle around midday. NightMostly cloudy, with a low around 57°F14°C. Breezy from the SE at 7 to 8 mph11 to 13 km/h. 27% chance of showers in the evening.
	WednesdaySep 30	73°F23°C	62°F17°C	0.33 in8.4 mm· 35%	82%	Light Rain	SSW 9 mph14 km/h
DayOvercast and warm, with a high of 73°F23°C and morning low of 62°F17°C. Breezy from the SSW at 9 to 10 mph15 to 16 km/h. 34% chance of light rain throughout the day. NightOvercast, with a low around 64°F18°C. Breezy from the S at 8 to 9 mph13 to 14 km/h. 35% chance of light rain throughout the night.
	ThursdayOct 1	72°F22°C	59°F15°C	0.24 in6.1 mm· 26%	63%	Showers	WSW 8 mph13 km/h
DayMostly cloudy and warm, with a high of 72°F22°C and morning low of 59°F15°C. Breezy from the WSW at 9 to 10 mph14 to 16 km/h. 26% chance of showers throughout the day. NightMostly cloudy, with a low around 61°F16°C. Breezy from the SW at 8 mph12 km/h. 24% chance of showers throughout the night.
	FridayOct 2	74°F23°C	57°F14°C	0.09 in2.3 mm· 17%	55%	Drizzle	SW 7 mph12 km/h
DayMostly cloudy and warm, with a high of 74°F23°C and morning low of 57°F14°C. Breezy from the WSW at 8 to 9 mph13 to 14 km/h. 14% chance of drizzle throughout the day. NightMostly cloudy, with a low around 58°F15°C. Breezy from the SSW at 7 mph11 km/h. 17% chance of drizzle throughout the night.
	SaturdayOct 3	73°F23°C	57°F14°C	0.11 in2.9 mm· 21%	57%	Showers	SSW 8 mph13 km/h
DayMostly cloudy and warm, with a high of 73°F23°C and morning low of 57°F14°C. Breezy from the SSW at 9 to 10 mph14 to 16 km/h. 21% chance of showers throughout the day. NightMostly cloudy, with a low around 58°F15°C. Breezy from the SSW at 7 to 8 mph12 to 13 km/h. 15% chance of showers throughout the night.
	SundayOct 4	71°F22°C	56°F14°C	0.13 in3.2 mm· 15%	56%	Showers	WSW 9 mph14 km/h
DayMostly cloudy and warm, with a high of 71°F22°C and morning low of 56°F14°C. Breezy from the WSW at 10 to 11 mph15 to 17 km/h. 15% chance of showers throughout the day. NightMostly cloudy, with a low around 58°F15°C. Breezy from the WSW at 8 mph13 km/h. 15% chance of showers throughout the night.
	MondayOct 5	70°F21°C	53°F12°C	0.11 in2.7 mm· 15%	48%	Drizzle	W 8 mph13 km/h
DayMostly cloudy and warm, with a high of 70°F21°C and morning low of 53°F12°C. Breezy from the W at 9 to 10 mph15 to 16 km/h. 15% chance of drizzle throughout the day. Dry air. NightPartly cloudy, with a low around 55°F13°C. Breezy from the WSW at 8 mph12 km/h. 15% chance of drizzle throughout the night.
	TuesdayOct 6	71°F22°C	52°F11°C	0.09 in2.3 mm· 13%	40%	Drizzle	WSW 8 mph13 km/h
DayPartly cloudy and warm, with a high of 71°F22°C and morning low of 52°F11°C. Breezy from the WSW at 9 to 10 mph14 to 15 km/h. 12% chance of drizzle throughout the day. Dry air. NightPartly cloudy, with a low around 54°F12°C. Breezy from the WSW at 7 to 8 mph12 to 13 km/h. 13% chance of drizzle throughout the night.
	WednesdayOct 7	70°F21°C	51°F10°C	0.11 in2.8 mm· 13%	38%	Drizzle	WNW 8 mph13 km/h
DayPartly cloudy and warm, with a high of 70°F21°C and morning low of 51°F10°C. Breezy from the WNW at 9 to 10 mph14 to 16 km/h. 13% chance of drizzle throughout the day. Dry air. NightPartly cloudy, with a low around 53°F12°C. Breezy from the WNW at 8 mph12 km/h. 12% chance of drizzle throughout the night.

Nearby Cities

Springfield37 mi59 km Mattoon40 mi64 km Champaign42 mi68 km Urbana44 mi70 km Bloomington45 mi72 km Normal47 mi75 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: 39.8403°N, 88.9548°W·Elevation: 205m·Timezone: America/Chicago·Population: 73,254