Fort Supply Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Fort Supply Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Fort Supply Reservoir today is 17.8°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 60°F (15°C) to 65°F (18°C). The water is comfortable for most people, making it an ideal range for water sports enthusiasts. The temperature does not cause significant discomfort, and swimming will be pleasant for the majority. However, it's important to remember that prolonged exposure to the water can still lead to cooling, so it's essential to monitor the time spent in the water, especially for children or elderly people. 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 | 19.4°C | 19.0°C | |
| OCT 6 | 19.2°C | 19.0°C | |
| OCT 7 | 18.4°C | 19.0°C | |
| OCT 8 | 18.3°C | 19.0°C | |
| OCT 9 | 18.1°C | 19.0°C | |
| OCT 10 | 17.8°C | 19.0°C | |
| OCT 11 | 18.2°C | 19.0°C | |
| OCT 12 | 18.1°C | 19.0°C | |
| OCT 13 | 19.0°C | 17.9°C | |
| OCT 14 | 19.0°C | 17.9°C | |
| OCT 15 | 19.0°C | 18.0°C | |
| OCT 16 | 19.0°C | 18.0°C | |
| OCT 17 | 19.0°C | 18.1°C | |
| OCT 18 | 19.0°C | 18.2°C | |
| OCT 19 | 19.0°C | 18.2°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 | 4°C | 8°C |
| February | 2°C | 5°C | 9°C |
| March | 3°C | 10°C | 18°C |
| April | 10°C | 15°C | 20°C |
| May | 13°C | 18°C | 24°C |
| June | 20°C | 23°C | 27°C |
| July | 23°C | 26°C | 30°C |
| August | 23°C | 27°C | 32°C |
| September | 22°C | 26°C | 30°C |
| October | 16°C | 19°C | 22°C |
| November | 10°C | 15°C | 19°C |
| December | 3°C | 7°C | 11°C |
Fort Supply Reservoir: Water Temperature by Location
Fort Supply Reservoir: Weather Forecast
October 13
October 14
October 15
October 16
October 17
Location & Local Information
Fort Supply Reservoir’s water temperature varies widely through the year because it is a relatively shallow prairie reservoir subject to strong seasonal swings. Typical surface temperatures in winter often sit near freezing up to about the mid-40s °F (around 0–7 °C). Spring warming usually raises surface values into the mid‑40s to mid‑60s °F (about 7–18 °C) as air temperatures and runoff increase. In summer, shallow bays and nearshore areas commonly warm into the mid‑70s to mid‑80s °F (24–30 °C) and can reach the upper 80s °F (around 31–32 °C) during heat waves, while deeper pockets remain noticeably cooler. Early fall tends to see a gradual decline back through the 60s and 50s °F (15–10 °C) as nights cool.
Swimming is generally permitted at Fort Supply Reservoir because it is managed for multiple recreational uses, but opportunities depend on facilities, water levels and posted advisories. There are areas where people enter the water from shore or boats, yet most sites lack lifeguards and conditions can change quickly, so swimmers take responsibility for their own safety. Cold‑water shock can be a hazard in shoulder seasons and occasional algal or bacteria advisories may restrict or discourage swimming in warm months; visitors should watch local signs and follow any posted restrictions before entering the water.