Walthamstow Reservoirs — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Walthamstow Reservoirs, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Walthamstow Reservoirs today is 17.9°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 |
|---|---|---|---|
| SEP 15 | 19.8°C | 21.0°C | |
| SEP 16 | 19.7°C | 21.0°C | |
| SEP 17 | 19.9°C | 21.0°C | |
| SEP 18 | 19.2°C | 21.0°C | |
| SEP 19 | 19.0°C | 21.0°C | |
| SEP 20 | 18.3°C | 21.0°C | |
| SEP 21 | 18.6°C | 21.0°C | |
| SEP 22 | 18.4°C | 21.0°C | |
| SEP 23 | 21.0°C | 18.1°C | |
| SEP 24 | 21.0°C | 18.2°C | |
| SEP 25 | 21.0°C | 18.4°C | |
| SEP 26 | 21.0°C | 18.5°C | |
| SEP 27 | 21.0°C | 18.7°C | |
| SEP 28 | 21.0°C | 18.8°C | |
| SEP 29 | 21.0°C | 19.0°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 | 14°C | 21°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 | 5°C | 10°C | 13°C |
| December | 4°C | 8°C | 11°C |
Walthamstow Reservoirs: Water Temperature by Location
Walthamstow Reservoirs: Weather Forecast
September 23
September 24
September 25
September 26
September 27
Location & Local Information
#Greater London
Walthamstow Reservoirs in northeast London are part of the Lee Valley chain and tend to stay cool year-round. Surface temperatures typically range from about 4–7°C (39–45°F) in midwinter, 8–15°C (46–59°F) in spring, 16–22°C (61–72°F) in summer and decline through autumn back towards single digits. Deep water remains colder than the surface, and even on warm days the reservoirs are noticeably cooler than shallow urban ponds or rivers.
Open-water swimming is generally not permitted at Walthamstow Reservoirs because they form part of the city's water-supply system and for public-safety reasons: cold-water shock, sudden depth changes, underwater hazards and occasional maintenance or operational activity present risks. Visitors instead use the area for waterside walking, birdwatching and fishing in designated spots. Nearby attractions include the Walthamstow Wetlands nature reserve with hides for wildlife viewing, the Lee Valley regional park and local cultural sites such as the William Morris Gallery and Walthamstow Market, making the area appealing for a day visit without swimming.