Search for cities, countries, lakes and rivers
Illinois River
Illinois River Current Water Temperature and Forecast
On this page, you will find comprehensive information about the water temperature in Illinois River, including current readings, historical data and trends, monthly averages, as well as weather forecasts and upcoming temperature predictions. We find every spot where you can swim and tell you what the water temperature is there today and throughout the year.
Current Water Temperature in Illinois River
42°F
TODAY
42°F
YESTERDAY
42°F
A WEEK AGO
As of today, the minimum water temperature in the Illinois River ranges less than 41°F (5°C). Such water is extremely cold and not recommended for swimming without proper preparation. In these conditions, the risk of hypothermia is very high, and prolonged exposure to the water can be hazardous to your health. If you decide to swim, it is important to have the appropriate gear, such as a wetsuit. Typically, only experienced swimmers or those who practice winter swimming venture into such waters.
It is important to note that these swimming tips and recommendations apply only in good weather. When the air temperature is below 68°F (20°C), and sometimes even below 77°F (25°C), swimming can be unpleasant even with relatively high water temperatures.
Analysis, Historical Data, and Forecast of Water Temperature
Water Temperature Chart for Illinois River Over the Last 30 Days
Today the water temperature in Illinois River is higher than the same day in previous years. The water temperature range here in February is from 37°F to 48°F. The water temperature is trending upward, and it has increased both over the past 30 days and the past week.
The forecasted water temperature values for Illinois River are presented in the table below.
The actual water temperature values near the shore may differ by a few degrees from the stated values. For the development of the forecast, we use our own mathematical model that takes into account the current water temperature changes, historical data, and key weather trends, including wind strength and direction, and air temperature in each specific region.
Daily Water Temperature Chart
| Date | Current | Average | Forecast |
|---|---|---|---|
| Feb 15 | 42°F | 42°F | |
| Feb 16 | 41°F | 42°F | |
| Feb 17 | 41°F | 42°F | |
| Feb 18 | 43°F | 42°F | |
| Feb 19 | 42°F | 42°F | |
| Feb 20 | 42°F | 42°F | |
| Feb 21 | 42°F | 42°F | |
| Feb 22 | 42°F | 42°F | |
| Feb 23 | 42°F | 42°F | |
| Feb 24 | 42°F | 42°F | |
| Feb 25 | 42°F | 42°F | |
| Feb 26 | 42°F | 42°F | |
| Feb 27 | 42°F | 42°F | |
| Feb 28 | 42°F | 42°F | |
| Mar 1 | 44°F | 42°F | |
| Mar 2 | 44°F | 42°F |
Water Temperature Ranges in Illinois River by Month
January
| Minimum | Average | Maximum |
|---|---|---|
| 37°F | 40°F | 48°F |
February
| Minimum | Average | Maximum |
|---|---|---|
| 37°F | 42°F | 48°F |
March
| Minimum | Average | Maximum |
|---|---|---|
| 37°F | 44°F | 52°F |
April
| Minimum | Average | Maximum |
|---|---|---|
| 41°F | 50°F | 61°F |
May
| Minimum | Average | Maximum |
|---|---|---|
| 46°F | 56°F | 70°F |
June
| Minimum | Average | Maximum |
|---|---|---|
| 57°F | 65°F | 72°F |
July
| Minimum | Average | Maximum |
|---|---|---|
| 63°F | 68°F | 75°F |
August
| Minimum | Average | Maximum |
|---|---|---|
| 63°F | 71°F | 73°F |
September
| Minimum | Average | Maximum |
|---|---|---|
| 52°F | 64°F | 66°F |
October
| Minimum | Average | Maximum |
|---|---|---|
| 46°F | 56°F | 61°F |
November
| Minimum | Average | Maximum |
|---|---|---|
| 37°F | 47°F | 61°F |
December
| Minimum | Average | Maximum |
|---|---|---|
| 37°F | 40°F | 46°F |
Monthly Water Temperature Histogram for Illinois River
Water Temperature in Cities and Towns on Illinois River
Illinois River Weather
FEBRUARY 23
16°F / 46°F
overcastrain: 1% | wind: 12 mph
FEBRUARY 24
32°F / 54°F
overcastrain: 3% | wind: 15 mph
FEBRUARY 25
37°F / 54°F
overcastrain: 16% | wind: 14 mph
FEBRUARY 26
39°F / 48°F
light drizzlerain: 34% | wind: 18 mph
FEBRUARY 27
32°F / 46°F
moderate drizzlerain: 34% | wind: 16 mph
Water Temperature in Illinois River: General Trends and Swimming Opportunities
Source Confluence of the Kankakee and Des Plaines Rivers
• location Grundy County, Illinois, United States
Mouth Mississippi River
• location Grafton, Illinois, United States
• elevation 417 ft (127 m)
Length 273 mi (439 km)
The Illinois River, flowing through the heart of Illinois, is a major waterway with diverse recreational opportunities. Its water temperature varies with the seasons, typically ranging from 35°F to 50°F (2°C to 10°C) during the cooler months and warming to 65°F–75°F (18°C–24°C) in the summer. These warmer temperatures in the summer make parts of the river more inviting for water-based activities, though swimming is not the primary focus for most visitors.
Swimming in the Illinois River is possible but is generally limited to specific areas where conditions are safe. Factors like water quality, variable currents, and boat traffic can make swimming less practical in many sections. Designated spots or nearby recreational areas, particularly in tributaries or smaller, calmer sections of the river, are better suited for a refreshing dip. The river is widely enjoyed for boating, fishing, and wildlife observation, providing locals and visitors with numerous ways to experience its beauty and significance in the region.
Geographical Location of Illinois River
Nearby Rivers
Frequently Asked Questions About Illinois River and its Water Temperatures
What is the current water temperature in Illinois River?
The water temperature today in Illinois River ranges from 35°F (1.8°C) to 37°F (2.7°C).
What is the water temperature in Illinois River during the summer months?
The average water temperature in Illinois River during the summer months is typically between 65°F to 71°F (19°C to 21°C), and it can reach up to 75°F (24°C) at its warmest. However, in some years, the temperature may exceed this range.
What is the water temperature in Illinois River in May?
The average water temperature in Illinois River in May ranges from 46°F to 70°F (8°C to 21°C).
What is the water temperature in Illinois River in September?
The average water temperature in Illinois River in September is typically between 52°F to 66°F (11°C to 19°C).
Where does Illinois River flow?
Illinois River flows through United States (Illinois).
Is it possible to swim in the Illinois River?
Yes, it is possible to swim in the Illinois River. However, safety and water quality may vary, so it's advisable to check local conditions.
What major cities are located on Illinois River?
Cities along the course of Illinois River include Peoria (Illinois).