Live Weather & Forecast
Weather in Decatur
Illinois, United States · Real-time conditions & 3-day outlook
27°C
Feels like 28°C
80°F / Feels 83°F
Partly cloudy
Decatur, Illinois
🌞 Daytime
Updated: 2026-04-13 14:15
Humidity
56%
Wind
26.6 km/h SSW
Wind Gust
30.6 km/h
Pressure
1014 mb
Visibility
16 km
UV Index
7.1
(High)
Precipitation
0 mm
Cloud Cover
50%
Dew Point
19.2°C
Wind Degree
199°
Air Quality Index
US EPA: Good
UK DEFRA: Low (1)
CO
147.9 μg/m³
NO₂
3.9 μg/m³
O₃
85 μg/m³
SO₂
1.4 μg/m³
PM 2.5
5.3 μg/m³
PM 10
6 μg/m³
Today's Hourly Forecast
24-hour breakdown for Decatur, Illinois
12 AM
19°
Patchy rain nearby
1 AM
19°
Clear
2 AM
19°
Clear
3 AM
19°
Clear
4 AM
19°
Clear
5 AM
19°
Cloudy
6 AM
19°
Overcast
7 AM
19°
Sunny
8 AM
21°
Sunny
9 AM
22°
Partly Cloudy
10 AM
23°
Partly Cloudy
11 AM
25°
Partly Cloudy
12 PM
26°
Cloudy
1 PM
27°
Partly Cloudy
2 PM
27°
Partly cloudy
3 PM
29°
Sunny
4 PM
29°
Sunny
5 PM
29°
Sunny
6 PM
28°
Sunny
7 PM
26°
Sunny
8 PM
25°
Clear
9 PM
24°
Clear
10 PM
24°
Clear
11 PM
23°
Clear
3-Day Forecast
Daily overview for Decatur, Illinois
Today
Sunny
30°
/
18°
🌧️ 0% chance of rain
💧 Avg. humidity: 67%
💨 Max wind: 33.8 km/h
🌧️ Total precip: 0.05 mm
☀️ UV Index: 1.7
🌅 Sunrise: 06:20 AM
🌇 Sunset: 07:32 PM
🌙 Waning Crescent
🌑 Moon: 23% lit
Tue, Apr 14
Patchy rain nearby
24°
/
19°
🌧️ 77% chance of rain
💧 Avg. humidity: 86%
💨 Max wind: 31.3 km/h
🌧️ Total precip: 2.02 mm
☀️ UV Index: 1.6
🌅 Sunrise: 06:19 AM
🌇 Sunset: 07:33 PM
🌙 Waning Crescent
🌑 Moon: 15% lit
Wed, Apr 15
Thundery outbreaks in nearby
24°
/
18°
🌧️ 0% chance of rain
💧 Avg. humidity: 83%
💨 Max wind: 31 km/h
🌧️ Total precip: 0 mm
☀️ UV Index: 0.7
🌅 Sunrise: 06:17 AM
🌇 Sunset: 07:34 PM
🌙 Waning Crescent
🌑 Moon: 8% lit
Best Time to Visit Decatur
Plan your trip to Decatur, United States around the most favorable weather conditions.
Peak Season
June – September
Warm, dry summers — ideal for outdoor activities.
Shoulder Season
April – May, October
Fewer crowds, moderate prices, mild weather.
Off Season
November – March
Cooler temperatures; some regions may experience rain or snow.
Frequently Asked Questions
What is the current weather in Decatur?
Current conditions in Decatur: Partly cloudy, temperature 27°C, humidity 56%.
What is the best time to visit Decatur?
The best time to visit Decatur is typically June – September. Warm, dry summers — ideal for outdoor activities.
What is the climate like in Decatur?
Decatur is located at approximately 39.8° latitude. It has a temperate climate with warm summers and cold winters.
Does it rain a lot in Decatur?
The wettest period in Decatur is typically during November – March. Cooler temperatures; some regions may experience rain or snow.
What should I pack for a trip to Decatur?
For visits to Decatur during June – September: light clothing and sun protection. For November – March: layers and a waterproof jacket are recommended.
What country is Decatur in?
Decatur is located in United States, in the state of Illinois.
What are the public holidays in Decatur in 2026?
View the 2026 public holidays for Decatur on our Holidays page.
What are the GPS coordinates used for the weather forecast in Decatur?
The weather forecast for Decatur uses coordinates 39.8454, -88.9524.