Castle Island Water Temperature and Wetsuit Guide

The water temperature (20 °C / 69 °F) at Castle Island is warm and the air temperature should feel similar (windchill forecast 16 °C / 61 °F). If the sun does come out as forecast, it should feel warm enough to surf in a shorty or a summer wetsuit.

Map of current Bermuda Surface Water Temperatures based on measurements from oceanographic satellites

Map of current Bermuda Sea Water Temperature Anomalies (compared with long term averages at this time of year)

(click thumbnails to expand)

Below is a graph of Historical Sea Surface Temperature for Castle Island. This has been derived from analysis of two decades of oceanographic satellite measurements of nearby open water. We have calculated the average water temperature variation around the year as well as the extremes that have been observed on each date.

All of the graphs for the surf breaks presented on Surf-Forecast.com are on the same scale to enable comparison between locations around the world.

Castle Island sea water temperatures peak in the range 26 to 29°C (79 to 84°F) on around the 6th of August and are at their minimum on about the 29th of February, in the range 19 to 20°C (66 to 68°F). Year round warm sea water temperatures at Castle Island climb to their maximum in the first week of August. Even then a rash vest and board shorts should be fine for surfing at any time of year. The minimum Castle Island sea water temperatures in late February require something like a 3/2mm fully sealed wetsuit.

Actual sea surface water temperatures close to shore at Castle Island can vary by several degrees compared with these open water averages. This is especially true after heavy rain, close to river mouths or after long periods of strong offshore winds. Offshore winds cause colder deep water to replace surface water that has been warmed by the sun. Air temperature, wind-chill and sunshine should also be considered before deciding on the kind of wetsuit needed to stay warm when surfing at Castle Island. Refer to our detailed weather forecasts for this information.

Latest surface water temperature for the entire globe. Click the image to view a larger version.