Summit Lake Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Summit Lake Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Summit Lake Reservoir today is 27.7°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 |
|---|---|---|---|
| AUG 4 | 26.8°C | 26.0°C | |
| AUG 5 | 26.7°C | 26.0°C | |
| AUG 6 | 26.9°C | 26.0°C | |
| AUG 7 | 26.8°C | 26.0°C | |
| AUG 8 | 26.8°C | 26.0°C | |
| AUG 9 | 27.4°C | 26.0°C | |
| AUG 10 | 27.5°C | 26.0°C | |
| AUG 11 | 27.8°C | 26.0°C | |
| AUG 12 | 26.0°C | 27.6°C | |
| AUG 13 | 26.0°C | 27.5°C | |
| AUG 14 | 26.0°C | 27.4°C | |
| AUG 15 | 26.0°C | 27.4°C | |
| AUG 16 | 26.0°C | 27.3°C | |
| AUG 17 | 26.0°C | 27.2°C | |
| AUG 18 | 26.0°C | 27.1°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 | 1°C | 6°C | 9°C |
| February | 1°C | 6°C | 10°C |
| March | 2°C | 6°C | 10°C |
| April | 6°C | 11°C | 16°C |
| May | 8°C | 14°C | 20°C |
| June | 16°C | 23°C | 30°C |
| July | 20°C | 24°C | 28°C |
| August | 23°C | 26°C | 29°C |
| September | 21°C | 25°C | 29°C |
| October | 17°C | 20°C | 22°C |
| November | 4°C | 11°C | 17°C |
| December | 2°C | 6°C | 9°C |
Summit Lake Reservoir: Water Temperature by Location
Summit Lake Reservoir: Weather Forecast
August 12
August 13
August 14
August 15
Location & Local Information
Summit Lake Reservoir, located in Summit Lake State Park in east‑central Indiana, experiences the typical seasonal swings of Midwestern lakes. In winter the surface often approaches freezing, roughly 32–40°F (0–4°C), and may develop ice depending on air temperatures. Spring sees a steady rise as runoff and warming air bring the surface into roughly 40–60°F (4–16°C). By mid‑ to late summer the shallow, sheltered water commonly warms to about 68–82°F (20–28°C), with occasional pockets reaching the upper 80s on heat‑wave days. In autumn the temperature falls again into the 50–65°F (10–18°C) range as cooling air and shorter days reduce surface warmth. Local factors such as recent rainfall, wind, and how deep you are in the lake can shift these values by several degrees.
Swimming is generally concentrated in the park’s designated beach area and is typically permitted during the warm season when the park opens the beach and staff or lifeguards are on duty; outside those posted times swimming may be at one’s own risk or restricted. Visitors should consider water temperature and conditions—colder shoulder‑season water can cause cold‑water shock, and summer conditions can bring wind or algae that affect safety—so following park signage and guidance is advisable before entering the water.