Lake Grafham Water — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Lake Grafham Water, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Lake Grafham Water today is 21.3°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
✅ As of today, the minimum water temperature ranges from 68°F (20°C) to 74°F (23°C). The water is warm and pleasant for swimming, and in this range, one can stay in the water for extended periods without the risk of hypothermia. This is the ideal temperature for relaxation, swimming, and water sports. Families with children, as well as outdoor enthusiasts, will enjoy swimming and time spent in the water. For most people, this is the optimal temperature for a comfortable beach experience. 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 25 | 20.8°C | 20.4°C | |
| JUN 26 | 20.8°C | 20.4°C | |
| JUN 27 | 22.1°C | 20.4°C | |
| JUN 28 | 22.2°C | 20.4°C | |
| JUN 29 | 22.2°C | 20.4°C | |
| JUN 30 | 22.5°C | 20.4°C | |
| JUL 1 | 21.4°C | 22.0°C | |
| JUL 2 | 21.3°C | 22.0°C | |
| JUL 3 | 22.0°C | 21.3°C | |
| JUL 4 | 22.0°C | 21.4°C | |
| JUL 5 | 22.0°C | 21.4°C | |
| JUL 6 | 22.0°C | 21.4°C | |
| JUL 7 | 22.0°C | 21.5°C | |
| JUL 8 | 22.0°C | 21.5°C | |
| JUL 9 | 22.0°C | 21.5°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 | 7°C |
| February | 1°C | 5°C | 8°C |
| March | 3°C | 7°C | 10°C |
| April | 7°C | 11°C | 14°C |
| May | 11°C | 17°C | 23°C |
| June | 14°C | 20°C | 26°C |
| July | 17°C | 22°C | 27°C |
| August | 17°C | 22°C | 27°C |
| September | 12°C | 18°C | 23°C |
| October | 9°C | 13°C | 17°C |
| November | 4°C | 8°C | 12°C |
| December | 1°C | 5°C | 8°C |
Lake Grafham Water: Water Temperature by Location
Lake Grafham Water: Weather Forecast
July 3
July 4
July 5
July 6
Location & Local Information
#Cambridgeshire
Grafham Water is a large reservoir in Cambridgeshire where surface water temperatures vary by season. In winter the water commonly sits around 4–7 °C (39–45 °F), rising in spring to roughly 6–14 °C (43–57 °F). Midsummer surface temperatures typically reach 14–22 °C (57–72 °F), occasionally a little higher in heatwaves, while autumn brings a cooling back to about 8–14 °C (46–57 °F). These figures are approximate and local conditions such as weather, depth and wind can change how warm the water feels at any one time.
Swimming in the reservoir is generally not permitted because Grafham is a working water supply and the owner restricts casual bathing for safety and water-quality reasons. That said, organised, supervised events and coached open-water sessions in designated areas are sometimes authorised under strict controls, and water-sports activities like sailing, kayaking and paddleboarding are widely available. The site also offers a visitor centre, nature reserve with birdwatching, walking and cycling trails, and nearby amenities for day visitors.