Live Weather & Forecast
Weather in Sullivan
Illinois, United States · Real-time conditions & 3-day outlook
20°C
Feels like 20°C
69°F / Feels 69°F
Clear
Sullivan, Illinois
🌙 Nighttime
Updated: 2026-04-13 04:15
Humidity
68%
Wind
24.1 km/h SSW
Wind Gust
39 km/h
Pressure
1014 mb
Visibility
16 km
UV Index
0
(Low)
Precipitation
0 mm
Cloud Cover
0%
Dew Point
15.3°C
Wind Degree
209°
Air Quality Index
US EPA: Good
UK DEFRA: Low (1)
CO
144.9 μg/m³
NO₂
3.1 μg/m³
O₃
71 μg/m³
SO₂
1.6 μg/m³
PM 2.5
4 μg/m³
PM 10
4.3 μg/m³
Weather Alerts 1
Met
· Moderate · Expected
Special Weather Statement issued April 12 at 10:23PM CDT by NWS Lincoln IL
Moderately strong winds out of the south to southwest will continue late this evening into the overnight hours. Expect a few sporadic gusts of 40 to 50 mph with more frequent gusts of 25 to 40 mph. These winds can make driving difficult, especially for high profile vehicles.
Today's Hourly Forecast
24-hour breakdown for Sullivan, Illinois
12 AM
20°
Patchy rain nearby
1 AM
20°
Clear
2 AM
20°
Clear
3 AM
19°
Clear
4 AM
20°
Clear
5 AM
19°
Overcast
6 AM
19°
Partly Cloudy
7 AM
20°
Partly Cloudy
8 AM
21°
Overcast
9 AM
22°
Cloudy
10 AM
23°
Partly Cloudy
11 AM
24°
Cloudy
12 PM
26°
Partly Cloudy
1 PM
27°
Partly Cloudy
2 PM
27°
Partly Cloudy
3 PM
28°
Partly Cloudy
4 PM
29°
Sunny
5 PM
25°
Sunny
6 PM
25°
Thundery outbreaks in nearby
7 PM
23°
Thundery outbreaks in nearby
8 PM
23°
Thundery outbreaks in nearby
9 PM
23°
Thundery outbreaks in nearby
10 PM
22°
Cloudy
11 PM
21°
Thundery outbreaks in nearby
3-Day Forecast
Daily overview for Sullivan, Illinois
Today
Partly Cloudy
30°
/
19°
🌧️ 0% chance of rain
💧 Avg. humidity: 72%
💨 Max wind: 34.9 km/h
🌧️ Total precip: 0.03 mm
☀️ UV Index: 1.8
🌅 Sunrise: 06:20 AM
🌇 Sunset: 07:31 PM
🌙 Waning Crescent
🌑 Moon: 23% lit
Tue, Apr 14
Overcast
24°
/
19°
🌧️ 0% chance of rain
💧 Avg. humidity: 81%
💨 Max wind: 33.5 km/h
🌧️ Total precip: 0 mm
☀️ UV Index: 1.7
🌅 Sunrise: 06:18 AM
🌇 Sunset: 07:32 PM
🌙 Waning Crescent
🌑 Moon: 15% lit
Wed, Apr 15
Moderate rain
22°
/
19°
🌧️ 89% chance of rain
💧 Avg. humidity: 87%
💨 Max wind: 34.9 km/h
🌧️ Total precip: 13.5 mm
☀️ UV Index: 0.8
🌅 Sunrise: 06:17 AM
🌇 Sunset: 07:33 PM
🌙 Waning Crescent
🌑 Moon: 8% lit
Best Time to Visit Sullivan
Plan your trip to Sullivan, 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 Sullivan?
Current conditions in Sullivan: Clear, temperature 20°C, humidity 68%.
What is the best time to visit Sullivan?
The best time to visit Sullivan is typically June – September. Warm, dry summers — ideal for outdoor activities.
What is the climate like in Sullivan?
Sullivan is located at approximately 39.6° latitude. It has a temperate climate with warm summers and cold winters.
Does it rain a lot in Sullivan?
The wettest period in Sullivan is typically during November – March. Cooler temperatures; some regions may experience rain or snow.
What should I pack for a trip to Sullivan?
For visits to Sullivan during June – September: light clothing and sun protection. For November – March: layers and a waterproof jacket are recommended.
What country is Sullivan in?
Sullivan is located in United States, in the state of Illinois.
What are the public holidays in Sullivan in 2026?
View the 2026 public holidays for Sullivan on our Holidays page.
What are the GPS coordinates used for the weather forecast in Sullivan?
The weather forecast for Sullivan uses coordinates 39.5995, -88.6078.