William Girling Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in William Girling Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in William Girling Reservoir today is 15.4°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 |
|---|---|---|---|
| JUN 3 | 17.2°C | 21.9°C | |
| JUN 4 | 17.2°C | 21.9°C | |
| JUN 5 | 17.2°C | 21.9°C | |
| JUN 6 | 17.2°C | 21.9°C | |
| JUN 7 | 16.5°C | 21.9°C | |
| JUN 8 | 15.8°C | 21.9°C | |
| JUN 10 | 15.8°C | 21.9°C | |
| JUN 11 | 21.9°C | 15.7°C | |
| JUN 12 | 21.9°C | 16.1°C | |
| JUN 13 | 21.9°C | 16.4°C | |
| JUN 14 | 21.9°C | 16.7°C | |
| JUN 15 | 21.9°C | 17.0°C | |
| JUN 16 | 21.9°C | 17.4°C | |
| JUN 17 | 21.9°C | 17.7°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 | 3°C | 7°C | 10°C |
| February | 4°C | 8°C | 11°C |
| March | 6°C | 10°C | 13°C |
| April | 9°C | 13°C | 17°C |
| May | 11°C | 17°C | 22°C |
| June | 15°C | 22°C | 28°C |
| July | 19°C | 24°C | 29°C |
| August | 18°C | 23°C | 28°C |
| September | 16°C | 21°C | 26°C |
| October | 11°C | 15°C | 19°C |
| November | 4°C | 9°C | 13°C |
| December | 4°C | 8°C | 11°C |
William Girling Reservoir: Water Temperature by Location
William Girling Reservoir: Weather Forecast
June 9
June 10
June 11
June 12
June 13
Location & Local Information
#Greater London
William Girling Reservoir, in the Lee Valley north of London, typically shows clear seasonal variation in surface water temperature. In winter the water commonly sits around 4–8 °C (39–46 °F), while spring warms to roughly 7–14 °C (45–57 °F) as daylight increases. Summer surface temperatures can reach about 15–22 °C (59–72 °F) on warmer days, and autumn declines again into the 8–14 °C (46–57 °F) range. Local weather, depth and flow mean temperatures can vary across the reservoir and change quickly with cold snaps or heat spells.
Swimming is generally not permitted at William Girling Reservoir because it is part of the potable water supply and is managed for safety and wildlife conservation; unrestricted bathing risks contamination, cold-water shock and disturbance to bird habitats. Visitors who want water-based activities should look to organised, authorised venues within the Lee Valley Regional Park or municipal pools. Nearby attractions include the Walthamstow Wetlands visitor centre, parts of Lee Valley Park and the wooded Trent Park, offering walking, birdwatching and cycling close to the reservoir.