Grassholme Reservoir — Current Water Temperature, Annual Trends and Forecast

This page provides information on the current water temperature in Grassholme Reservoir, trends, monthly ranges and the forecast for the coming days.

Cow Green Reservoir, United Kingdom © By Paul White, CC BY-SA 4.0

Current Water Temperature

10.2°C

Today

10.5°C

Yesterday

11.1°C

A Week Ago

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Water Temperature in Grassholme Reservoir today is 10.2°C.

Water Temperature: Daily Trends, Historical Records, and Forecast

❌ As of today, the minimum water temperature ranges from 50°F (10°C) to 54°F (12°C). The water is slightly warmer, but still cool for most people. Swimming in such conditions is possible, but for most people, the time spent in the water should be limited to avoid hypothermia. Even experienced swimmers may feel discomfort if they stay in the water for too long. To improve comfort and safety, a wetsuit can be used. 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

From September 13 to October 14

Table of Daily Sea Temperature Data

Date	Current	Average	Forecast
OCT 7	11.1°C	12.0°C
OCT 8	11.0°C	12.0°C
OCT 9	10.9°C	12.0°C
OCT 10	10.3°C	12.0°C
OCT 11	10.6°C	12.0°C
OCT 12	10.5°C	12.0°C
OCT 13	10.5°C	12.0°C
OCT 14	9.9°C	12.0°C
OCT 15		12.0°C	10.3°C
OCT 16		12.0°C	10.4°C
OCT 17		12.0°C	10.5°C
OCT 18		12.0°C	10.6°C
OCT 19		12.0°C	10.7°C
OCT 20		12.0°C	10.7°C
OCT 21		12.0°C	10.8°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	0°C	4°C	7°C
March	2°C	6°C	9°C
April	5°C	9°C	12°C
May	9°C	14°C	20°C
June	12°C	19°C	25°C
July	14°C	21°C	26°C
August	15°C	21°C	26°C
September	12°C	18°C	23°C
October	8°C	12°C	15°C
November	4°C	8°C	11°C
December	0°C	3°C	7°C

Grassholme Reservoir: Water Temperature by Location

🇬🇧 United Kingdom > England

Grassholme Reservoir: Weather Forecast

October 15

° / °

slight rain

rain: 68% | wind:

October 16

° / °

light drizzle

rain: 35% | wind:

October 17

° / °

overcast

snow: 20% | wind:

October 18

° / °

overcast

rain: 20% | wind:

Location & Local Information

#County Durham

Grassholme Reservoir in County Durham sits high in Teesdale and is fed by cool upland water, so temperatures stay fairly low year-round. In winter the surface typically falls to around 4–8 °C (39–46 °F). Spring can see a gradual rise, often 6–14 °C (43–57 °F) as the weather warms, while summer surface readings commonly range from about 12–18 °C (54–64 °F) on warmer days. In autumn the water cools again to roughly 8–12 °C (46–54 °F). These are typical seasonal surface values; deeper water remains colder and conditions change with weather and inflows.

There is no formal, supervised bathing area at Grassholme and open-water swimming is generally discouraged or restricted. Reasons include cold water that can cause shock, variable depths and submerged hazards, limited access for emergency services, and the reservoir’s role in water supply and fisheries management. Visitors instead use the area for walking, birdwatching and angling. Nearby attractions in Upper Teesdale include scenic riverside trails, nature reserves and the well-known High Force waterfall, making the spot popular for outdoor day visits rather than casual swimming.

Nearby Lakes

Frequently Asked Questions

What is the current water temperature in Grassholme Reservoir?

Water Temperature in Grassholme Reservoir today is 10.2°C.

What is the water temperature in Grassholme Reservoir during the summer months?

The water temperature in Grassholme Reservoir in summer fluctuates in the range of 12°C - 26°C.

Is it possible to swim in Grassholme Reservoir (United Kingdom) and what are the possibilities for this?

Wild swimming at Grassholme Reservoir is generally not permitted for safety and water-supply reasons, but swimming may be possible only as part of organised, supervised events or with prior permission from the reservoir operator, and authorised clubs sometimes run other watersports under agreed conditions.