Carmarthen — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Carmarthen, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Carmarthen today is 19.6°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 65°F (18°C) to 68°F (20°C). This is already quite warm water, which is ideal for most people. Swimming becomes comfortable, and prolonged stays in the water do not cause discomfort. This temperature is perfect for family trips and for those who prefer warmer water. It is also comfortable for water sports such as surfing or swimming. 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 |
|---|---|---|---|
| AUG 6 | 18.9°C | 19.0°C | |
| AUG 7 | 18.8°C | 19.0°C | |
| AUG 8 | 18.8°C | 19.0°C | |
| AUG 9 | 18.8°C | 19.0°C | |
| AUG 10 | 19.2°C | 19.0°C | |
| AUG 11 | 19.2°C | 19.0°C | |
| AUG 12 | 19.2°C | 19.0°C | |
| AUG 13 | 19.2°C | 19.0°C | |
| AUG 14 | 19.0°C | 19.6°C | |
| AUG 15 | 19.0°C | 19.5°C | |
| AUG 16 | 19.0°C | 19.5°C | |
| AUG 17 | 19.0°C | 19.5°C | |
| AUG 18 | 19.0°C | 19.5°C | |
| AUG 19 | 19.0°C | 19.4°C | |
| AUG 20 | 19.0°C | 19.4°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 | 2°C | 6°C | 9°C |
| February | 3°C | 7°C | 9°C |
| March | 5°C | 9°C | 11°C |
| April | 7°C | 11°C | 14°C |
| May | 9°C | 14°C | 18°C |
| June | 12°C | 19°C | 24°C |
| July | 15°C | 20°C | 25°C |
| August | 15°C | 19°C | 24°C |
| September | 13°C | 18°C | 22°C |
| October | 9°C | 13°C | 16°C |
| November | 5°C | 9°C | 11°C |
| December | 3°C | 7°C | 9°C |
Carmarthen: Weather Forecast
August 14
August 15
August 16
Location & Local Information
The Welsh county town of Carmarthen sits on the River Towy, a major waterway with water temperatures that fluctuate significantly throughout the year. As the river originates in the high Cambrian Mountains, it remains cool, typically dropping to a cold range of 3∘C to 7∘C (37∘F to 45∘F) during the winter. Even in summer, the water remains brisk, usually peaking around 16∘C to 20∘C (61∘F to 68∘F) in the lower, slower reaches near the town, making a full swim a bracing experience.
Swimming in the River Towy in and around Carmarthen is generally not permitted or advised due to significant hazards. Strong, unpredictable currents, especially after rain, and deep water areas pose serious safety risks like cold water shock and drowning. Furthermore, the river has been flagged for water quality concerns, including pollution from sewage discharges, which makes unsupervised bathing a health risk. Visitors to Carmarthen can instead explore the town's rich history, including its Roman past and the ruins of Carmarthen Castle. The beautiful National Botanic Garden of Wales and the coastal village of Llansteffan, overlooking the Towy estuary, are also popular nearby attractions.