River Bann — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in the River Bann, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in the River Bann today is 11.8°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
Table of Daily Sea Temperature Data
| Date | Current | Average | Forecast |
|---|---|---|---|
| OCT 7 | 12.2°C | 9.0°C | |
| OCT 8 | 11.7°C | 9.0°C | |
| OCT 9 | 11.9°C | 9.0°C | |
| OCT 10 | 11.1°C | 9.0°C | |
| OCT 11 | 11.7°C | 9.0°C | |
| OCT 12 | 10.4°C | 9.0°C | |
| OCT 13 | 11.0°C | 9.0°C | |
| OCT 14 | 11.5°C | 9.0°C | |
| OCT 15 | 9.0°C | 11.7°C | |
| OCT 16 | 9.0°C | 11.5°C | |
| OCT 17 | 9.0°C | 11.4°C | |
| OCT 18 | 9.0°C | 11.2°C | |
| OCT 19 | 9.0°C | 11.1°C | |
| OCT 20 | 9.0°C | 11.0°C | |
| OCT 21 | 9.0°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 | 3°C | 6°C |
| February | 0°C | 3°C | 7°C |
| March | 1°C | 5°C | 8°C |
| April | 4°C | 7°C | 11°C |
| May | 8°C | 12°C | 17°C |
| June | 11°C | 16°C | 21°C |
| July | 12°C | 17°C | 21°C |
| August | 12°C | 17°C | 21°C |
| September | 9°C | 14°C | 18°C |
| October | 6°C | 9°C | 12°C |
| November | 4°C | 8°C | 12°C |
| December | 0°C | 4°C | 8°C |
River Bann: Water Temperature by Location
River Bann: Weather Forecast
October 15
October 16
October 17
October 18
Location & Local Information
Source:
• location Slieve Muck, County Down
Mouth:
• location Atlantic Ocean at Portstewart
• coordinates 55.17175°N 6.77264°W
Length 129 km (80 mi)
The River Bann, Northern Ireland’s longest river, flows from the Mourne Mountains through Lough Neagh and onward to the Atlantic Ocean at Coleraine. Its temperature reflects both upland and coastal influences, remaining cool for much of the year. In winter, the Bann averages about 4–6°C (39–43°F), staying cold and brisk. As spring progresses, the water slowly warms to around 8–11°C (46–52°F). During the summer months, especially in July and August, surface temperatures can reach 15–17°C (59–63°F), occasionally higher in sheltered sections. By early autumn, the river cools again to roughly 10–12°C (50–54°F), maintaining a fresh and clear character throughout the year.
Swimming in the River Bann is permitted and enjoyed by experienced open-water swimmers, though conditions vary greatly along its length. The upper river and Lough Neagh offer calm, scenic sections suitable for summer swimming, while the lower Bann near the coast is influenced by tides and currents, requiring more caution. The water quality is generally good, but cold temperatures and changing flow rates demand care and proper preparation. Alongside swimming, the Bann is popular for kayaking, fishing, and riverside walks. Nearby attractions include the Causeway Coast, Mountsandel Wood, and the historic towns of Portglenone and Coleraine, where the river remains a defining feature of the landscape.