Lake Jacksonville — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Lake Jacksonville, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Lake Jacksonville today is 26.1°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
✅ As of today, the minimum water temperature ranges from 79°F (26°C) to 82°F (28°C). This is very warm water, allowing for extended stays without any discomfort. Swimming in these conditions will be particularly enjoyable, making it the ideal temperature range for those who want to relax in the sea. Additionally, water in this temperature range is suitable for children and elderly people, as it is comfortable for prolonged stays. 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 |
|---|---|---|---|
| JUN 2 | 22.4°C | 22.6°C | |
| JUN 3 | 22.5°C | 22.6°C | |
| JUN 4 | 22.9°C | 22.6°C | |
| JUN 5 | 22.9°C | 22.6°C | |
| JUN 6 | 23.1°C | 22.6°C | |
| JUN 7 | 25.1°C | 22.6°C | |
| JUN 8 | 25.5°C | 22.6°C | |
| JUN 10 | 22.6°C | 25.9°C | |
| JUN 11 | 22.6°C | 25.8°C | |
| JUN 12 | 22.6°C | 25.6°C | |
| JUN 13 | 22.6°C | 25.4°C | |
| JUN 14 | 22.6°C | 25.2°C | |
| JUN 15 | 22.6°C | 25.1°C | |
| JUN 16 | 22.6°C | 24.9°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 | 0°C | 2°C | 5°C |
| February | 1°C | 4°C | 6°C |
| March | 3°C | 7°C | 11°C |
| April | 8°C | 13°C | 19°C |
| May | 15°C | 19°C | 24°C |
| June | 19°C | 23°C | 27°C |
| July | 24°C | 28°C | 31°C |
| August | 23°C | 26°C | 28°C |
| September | 22°C | 24°C | 27°C |
| October | 18°C | 21°C | 24°C |
| November | 6°C | 12°C | 18°C |
| December | 1°C | 4°C | 8°C |
Lake Jacksonville: Water Temperature by Location
Lake Jacksonville: Weather Forecast
June 9
June 10
June 11
June 12
June 13
Location & Local Information
Lake Jacksonville is a midwestern reservoir whose surface water temperature follows the seasonal cycle typical of inland Illinois lakes. In winter the lake hovers near freezing, roughly 32–40°F (0–4°C). As air temperatures warm in spring the surface climbs into the mid-40s to mid-60s Fahrenheit (about 7–18°C). Peak summer surface readings commonly reach the low 70s to low 80s °F (approximately 21–28°C), particularly in shallow, sheltered areas on calm days. In autumn the water cools again, often settling into a 50–65°F range (10–18°C) before approaching winter lows. Local weather, wind, and depth create variability from day to day and between shallow and deep sections.
Swimming is generally permitted at Lake Jacksonville in designated areas during the warmer months when beach facilities are open and public health officials have cleared the water. Access and hours are controlled by the managing agency, and swimming may be restricted temporarily for safety reasons such as poor water quality (algal blooms or bacterial contamination), hazardous conditions, or lack of lifeguard coverage. Because temperatures outside summer are often brisk and currents or sudden depth changes can occur, most recreational swimming is concentrated in late spring through summer when surface temperatures are most comfortable and seasonal oversight is in place.