Live Weather & Forecast

Weather in DeKalb

Illinois, United States · Real-time conditions & 3-day outlook

Flag of United States
Overcast
16°C
Feels like 16°C
61°F / Feels 61°F
Overcast
DeKalb, Illinois
🌞 Daytime
Updated: 2026-04-12 09:30
💧
Humidity
84%
💨
Wind
24.5 km/h SSW
🌬️
Wind Gust
37.8 km/h
🌡️
Pressure
1015 mb
👁️
Visibility
16 km
☀️
UV Index
0.8 (Low)
🌧️
Precipitation
0 mm
☁️
Cloud Cover
100%
💦
Dew Point
13.7°C
🌐
Wind Degree
198°

Air Quality Index

US EPA: Good UK DEFRA: Low (1)
CO
153.9 μg/m³
NO₂
2 μg/m³
O₃
105 μg/m³
SO₂
1.8 μg/m³
PM 2.5
6.5 μg/m³
PM 10
7 μg/m³

Weather Alerts 2

Met · Severe · Immediate
Flood Warning issued April 11 at 10:46AM CDT by NWS Chicago IL

...The Flood Warning continues for the following rivers in Illinois... Fox River at Algonquin Lock & Dam tailwater affecting Kane, Lake IL and McHenry Counties. For the Fox River (Illinois)...including Algonquin Lock & Dam tailwater...Minor flooding is occurring. * WHAT...Minor flooding is occurring and minor flooding is forecast. * WHERE...Fox River from Johnsburg downstream to Red Gate Road...

A Flood Warning means water levels above flood stage are imminent or may already be occurring. Persons along rivers and streams in the warned area should take immediate precautions to protect life and property. These forecasts are based on observed precipitation as well as forecast precipitation...

Effective: 2026-04-11T10:46:00-05:00  ·  Expires: 2026-04-12T05:00:00-05:00
Met · Severe · Immediate
Flood Warning issued April 11 at 9:24PM CDT until April 14 at 7:00PM CDT by NWS Chicago IL

...The Flood Warning continues for the following rivers in Illinois...Indiana... Fox River at Algonquin Lock & Dam tailwater affecting Lake IL, McHenry and Kane Counties. Kankakee River at Dunns Bridge affecting Jasper and Porter Counties. Kankakee River at Shelby affecting Newton and Lake IN Counties. ...The Flood Warning is extended for the following rivers in Illinois... Des Plaines River...

A Flood Warning means water levels above flood stage are imminent or may already be occurring. Persons along rivers and streams in the warned area should take immediate precautions to protect life and property. These forecasts are based on observed precipitation as well as forecast precipitation...

Effective: 2026-04-11T21:24:00-05:00  ·  Expires: 2026-04-12T15:30:00-05:00

Today's Hourly Forecast

24-hour breakdown for DeKalb, Illinois

12 AM
Clear
10°
Clear
💧 70% 💨 21.2 km/h
1 AM
Clear
10°
Clear
💧 73% 💨 19.1 km/h
2 AM
Clear
10°
Clear
💧 74% 💨 22 km/h
3 AM
Clear
10°
Clear
💧 77% 💨 21.6 km/h
4 AM
Clear
10°
Clear
💧 77% 💨 20.9 km/h
5 AM
Clear
11°
Clear
💧 80% 💨 21.2 km/h
6 AM
Clear
12°
Clear
💧 85% 💨 23.8 km/h
7 AM
Sunny
13°
Sunny
💧 88% 💨 25.2 km/h
8 AM
Sunny
15°
Sunny
💧 86% 💨 24.5 km/h
9 AM
Overcast
16°
Overcast
💧 84% 💨 24.5 km/h
10 AM
Sunny
20°
Sunny
💧 77% 💨 29.2 km/h
11 AM
Sunny
23°
Sunny
💧 73% 💨 30.6 km/h
12 PM
Sunny
25°
Sunny
💧 67% 💨 32 km/h
1 PM
Sunny
27°
Sunny
💧 57% 💨 34.2 km/h
2 PM
Sunny
26°
Sunny
💧 50% 💨 31 km/h
3 PM
Sunny
25°
Sunny
💧 53% 💨 32 km/h
4 PM
Partly Cloudy
23°
Partly Cloudy
💧 53% 💨 32.4 km/h
5 PM
Overcast
22°
Overcast
💧 73% 💨 26.3 km/h
6 PM
Overcast
20°
Overcast
💧 77% 💨 16.6 km/h
7 PM
Moderate rain
19°
Moderate rain
💧 97% 💨 16.2 km/h 🌧️ 100%
8 PM
Overcast
18°
Overcast
💧 98% 💨 26.3 km/h
9 PM
Overcast
17°
Overcast
💧 97% 💨 32 km/h
10 PM
Heavy rain
17°
Heavy rain
💧 98% 💨 32.4 km/h 🌧️ 100%
11 PM
Overcast
17°
Overcast
💧 97% 💨 29.2 km/h

3-Day Forecast

Daily overview for DeKalb, Illinois

Today
Moderate rain
Moderate rain
28° / 10°
🌧️ 79% chance of rain
💧 Avg. humidity: 77%
💨 Max wind: 34.2 km/h
🌧️ Total precip: 18.46 mm
☀️ UV Index: 0.9
🌅 Sunrise: 06:19 AM
🌇 Sunset: 07:33 PM
🌙 Waning Crescent
🌑 Moon: 33% lit
Mon, Apr 13
Heavy rain
Heavy rain
23° / 16°
🌧️ 80% chance of rain
💧 Avg. humidity: 92%
💨 Max wind: 29.2 km/h
🌧️ Total precip: 20.11 mm
☀️ UV Index: 1
🌅 Sunrise: 06:17 AM
🌇 Sunset: 07:34 PM
🌙 Waning Crescent
🌑 Moon: 23% lit
Tue, Apr 14
Thundery outbreaks in nearby
Thundery outbreaks in nearby
26° / 19°
🌧️ 0% chance of rain
💧 Avg. humidity: 90%
💨 Max wind: 36.7 km/h
🌧️ Total precip: 0 mm
☀️ UV Index: 0.8
🌅 Sunrise: 06:16 AM
🌇 Sunset: 07:35 PM
🌙 Waning Crescent
🌑 Moon: 15% lit

Best Time to Visit DeKalb

Plan your trip to DeKalb, 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.
← Back to DeKalb 🗓 View Holidays 2026

Frequently Asked Questions

What is the current weather in DeKalb?
Current conditions in DeKalb: Overcast, temperature 16°C, humidity 84%.
What is the best time to visit DeKalb?
The best time to visit DeKalb is typically June – September. Warm, dry summers — ideal for outdoor activities.
What is the climate like in DeKalb?
DeKalb is located at approximately 41.9° latitude. It has a temperate climate with warm summers and cold winters.
Does it rain a lot in DeKalb?
The wettest period in DeKalb is typically during November – March. Cooler temperatures; some regions may experience rain or snow.
What should I pack for a trip to DeKalb?
For visits to DeKalb during June – September: light clothing and sun protection. For November – March: layers and a waterproof jacket are recommended.
What country is DeKalb in?
DeKalb is located in United States, in the state of Illinois.
What are the public holidays in DeKalb in 2026?
View the 2026 public holidays for DeKalb on our Holidays page.
What are the GPS coordinates used for the weather forecast in DeKalb?
The weather forecast for DeKalb uses coordinates 41.9299, -88.7502.