East Fork Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in East Fork Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in East Fork Lake today is 19.3°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 65°F (18°C) to 68°F (20°C). This is already quite warm water, which is ideal for most people. Swimming becomes comfortable, and prolonged stays in the water do not cause discomfort. This temperature is perfect for family trips and for those who prefer warmer water. It is also comfortable for water sports such as surfing or swimming. 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.
Water Temperature Chart Over the Last 30 Days
Table of Daily Sea Temperature Data
| Date | Current | Average | Forecast |
|---|---|---|---|
| OCT 5 | 21.5°C | 20.5°C | |
| OCT 6 | 21.5°C | 20.5°C | |
| OCT 7 | 20.9°C | 20.5°C | |
| OCT 8 | 20.2°C | 20.5°C | |
| OCT 9 | 20.5°C | 20.5°C | |
| OCT 10 | 20.6°C | 20.5°C | |
| OCT 11 | 19.8°C | 20.5°C | |
| OCT 12 | 20.0°C | 20.5°C | |
| OCT 13 | 20.5°C | 19.4°C | |
| OCT 14 | 20.5°C | 19.4°C | |
| OCT 15 | 20.5°C | 19.5°C | |
| OCT 16 | 20.5°C | 19.5°C | |
| OCT 17 | 20.5°C | 19.6°C | |
| OCT 18 | 20.5°C | 19.7°C | |
| OCT 19 | 20.5°C | 19.7°C |
* Current - Actual water temperature value
** Average - Average water temperature on this day in recent years
*** Forecast - Our water temperature forecast
Actual nearshore water temperatures may fluctuate by several degrees from the reported values, especially following heavy rainfall or extended periods of strong winds. Certain wind patterns can cause colder, deeper waters to rise and replace the sun-warmed surface water, leading to noticeable variations.
Our forecast is based on a proprietary mathematical model that considers real-time water temperature changes, historical trends, key weather patterns, wind strength and direction, and air temperature specific to each region. Additionally, we incorporate data from other resorts to enhance accuracy.
Monthly Water Temperature Range (Min, Max & Average)
| Month | Min | Avg | Max |
|---|---|---|---|
| January | 2°C | 4°C | 7°C |
| February | 0°C | 5°C | 10°C |
| March | 0°C | 8°C | 15°C |
| April | 11°C | 15°C | 20°C |
| May | 17°C | 21°C | 24°C |
| June | 21°C | 25°C | 29°C |
| July | 25°C | 30°C | 33°C |
| August | 25°C | 28°C | 30°C |
| September | 24°C | 28°C | 32°C |
| October | 15°C | 21°C | 26°C |
| November | 8°C | 13°C | 18°C |
| December | 3°C | 7°C | 9°C |
East Fork Lake: Water Temperature by Location
East Fork Lake: Weather Forecast
October 13
October 14
October 15
October 16
October 17
October 18
Location & Local Information
East Fork Lake in Illinois follows the seasonal pattern typical of Midwestern reservoirs. In winter the surface often approaches freezing, around 32°F (0°C) and may be ice-covered for periods, while early spring temperatures commonly sit in the 40s°F (4–9°C). By late spring and into summer the water warms into the 60s–70s°F (16–24°C), with midsummer surface temperatures frequently reaching the mid-70s to low 80s°F (24–28°C) on warm years. In autumn the lake cools back through the 60s and 50s°F (10–16°C) as air temperatures drop. These are typical surface ranges; deeper water stays colder year-round.
Swimming is generally allowed in designated swimming areas when the managing agency posts them open, because park staff or local authorities maintain a beach area and monitor water conditions. Access may be restricted for safety reasons — low water quality, harmful algal blooms, strong currents, ice in winter, or hazardous boating activity can prompt closures — and lifeguards are not always present, so swimming is often at your own risk. Visitors should check current advisories and signage before entering the water and be aware of cold-water shock in shoulder seasons and potential summer algae advisories.