Irish Sea water temperature
Irish Sea, Rosslare · Sea/Coast
The current water temperature at Irish Sea is 15.2 °C (as of September 20, 2026, source: Open-Meteo marine model).
The sea lags the air by weeks: the warmest water often arrives after the warmest days. Measured buoy values show this honestly.
Water quality
EU classification: excellentMeasurement series & statistics
This measurement series includes 609 data points since July 22, 2026.
Lowest recorded value: 15.2 °C on September 18, 2026 · highest value: 19.9 °C on August 12, 2026.
In September, temperatures have ranged between 15.2 °C and 17.7 °C.
The current value is 1.1 °C below the September average of this series.
Nearby waters
More measuring points: Irish Sea
Frequently asked questions
Can you swim at Irish Sea right now?
The current water temperature is 15.2 °C. See live swimming conditions, weather and quality in the BrrChecker app.
How warm is the water at Irish Sea?
Currently 15.2 °C (updated continuously).
How warm is at Irish Sea in September?
In September, the water temperature recently averaged 16.3 °C.
When is the water warmest at Irish Sea?
Across the measurement record, July is on average the warmest month (18.5 °C).
How is the water quality at Irish Sea?
The official classification is: excellent.
