Castlerock Weather & Climate: Best Time to Visit

The weather in Castlerock changes moderately throughout the year, offering enough variation to appreciate each season. On average, daytime temperatures range from a moderate 17°C (63°F) in August to a chilly 9°C (48°F) in February.

Nighttime temperatures range from 13°C (55°F) in August to 5°C (41°F) in February.

Check out our detailed temperature page for more information.

Temperature ranges by month

Castlerock has a notably wet climate with abundant precipitation, recording 1332 mm (52 in) of rainfall per year. The amount of precipitation varies moderately throughout the year. The wettest month, November, sees around 141 mm (5.6 in) of rainfall, perfect for those who enjoy a bit of rain now and then. The driest month, May, still receives a respectable 81 mm (3.2 in) of rainfall. For more details, please visit our Castlerock Precipitation page.

The mean monthly precipitation over the year, including rain, hail, and snow

The average number of days each month with precipitation

In Castlerock, summer days are longer and more sunny, with daily sunshine hours peaking at 6.8 hours in May. As the darker season arrives, the brightness of the sun becomes less. December sees a soft sun for only 1.3 hours per average day.

Visit our detailed sunshine hours page for more information.

Monthly hours of sunshine

Daily hours of sunshine