Live Weather & Forecast
Weather in Ottawa
Illinois, United States · Real-time conditions & 3-day outlook
-1°C
Feels like -2°C
31°F / Feels 29°F
Clear
Ottawa, Illinois
🌙 Nighttime
Updated: 2026-04-12 05:15
Humidity
64%
Wind
3.6 km/h E
Wind Gust
7.3 km/h
Pressure
1030 mb
Visibility
24 km
UV Index
0
(Low)
Precipitation
0 mm
Cloud Cover
0%
Dew Point
-1.7°C
Wind Degree
80°
Air Quality Index
US EPA: Good
UK DEFRA: Low (1)
CO
412.9 μg/m³
NO₂
12.1 μg/m³
O₃
67 μg/m³
SO₂
4.5 μg/m³
PM 2.5
11.9 μg/m³
PM 10
13.4 μg/m³
Today's Hourly Forecast
24-hour breakdown for Ottawa, Illinois
12 AM
1°
Clear
1 AM
0°
Clear
2 AM
0°
Clear
3 AM
-0°
Clear
4 AM
-0°
Clear
5 AM
-1°
Clear
6 AM
-0°
Clear
7 AM
0°
Sunny
8 AM
2°
Sunny
9 AM
4°
Sunny
10 AM
6°
Sunny
11 AM
8°
Sunny
12 PM
9°
Sunny
1 PM
10°
Sunny
2 PM
11°
Sunny
3 PM
11°
Sunny
4 PM
10°
Cloudy
5 PM
8°
Patchy rain nearby
6 PM
6°
Overcast
7 PM
5°
Overcast
8 PM
5°
Light rain
9 PM
5°
Overcast
10 PM
4°
Overcast
11 PM
6°
Moderate rain
3-Day Forecast
Daily overview for Ottawa, Illinois
Today
Moderate rain
12°
/
-0°
🌧️ 83% chance of rain
💧 Avg. humidity: 79%
💨 Max wind: 17.3 km/h
🌧️ Total precip: 8.72 mm
☀️ UV Index: 0.8
🌅 Sunrise: 06:22 AM
🌇 Sunset: 07:45 PM
🌙 Waning Crescent
🌑 Moon: 33% lit
Mon, Apr 13
Heavy rain
15°
/
4°
🌧️ 88% chance of rain
💧 Avg. humidity: 91%
💨 Max wind: 27.4 km/h
🌧️ Total precip: 115.96 mm
☀️ UV Index: 0.2
🌅 Sunrise: 06:21 AM
🌇 Sunset: 07:47 PM
🌙 Waning Crescent
🌑 Moon: 23% lit
Tue, Apr 14
Heavy rain
19°
/
5°
🌧️ 87% chance of rain
💧 Avg. humidity: 92%
💨 Max wind: 23.8 km/h
🌧️ Total precip: 21.19 mm
☀️ UV Index: 0.4
🌅 Sunrise: 06:19 AM
🌇 Sunset: 07:48 PM
🌙 Waning Crescent
🌑 Moon: 15% lit
Best Time to Visit Ottawa
Plan your trip to Ottawa, 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
People also ask — answers optimized for search engines and voice queries.
What is the current weather in Ottawa?
Current conditions in Ottawa: Clear, temperature -1°C, humidity 64%.
What is the best time to visit Ottawa?
The best time to visit Ottawa is typically June – September. Warm, dry summers — ideal for outdoor activities.
What is the climate like in Ottawa?
Ottawa is located at approximately 45.4° latitude. It has a temperate climate with warm summers and cold winters.
Does it rain a lot in Ottawa?
The wettest period in Ottawa is typically during November – March. Cooler temperatures; some regions may experience rain or snow.
What should I pack for a trip to Ottawa?
For visits to Ottawa during June – September: light clothing and sun protection. For November – March: layers and a waterproof jacket are recommended.
What country is Ottawa in?
Ottawa is located in United States, in the state of Illinois.
What are the public holidays in Ottawa in 2026?
View the 2026 public holidays for Ottawa on our Holidays page.
What are the GPS coordinates used for the weather forecast in Ottawa?
The weather forecast for Ottawa uses coordinates 45.4209, -75.6901.