Sea Temperature in Harwich in September

© Steven Spatola

Complete information on the sea temperature range in the Atlantic Ocean in Harwich in September. Historical daily data. Climate details for September. Tips on swimming conditions and beach relaxation in Harwich. We find every spot where you can swim and tell you what the water temperature is there today and throughout the year.

Harwich Climate and Swimming Opportunities in September

Harwich lies within the Massachusetts in United States. The average daytime temperature in Harwich in September is 72°F (22°C), while the nighttime average is 58°F (14°C). There are typically nine rainy days during the month, with a total precipitation of 3.5 inches (89 mm). The daylight duration in September in Harwich is 12 hours, with an average of 7 hours of sunshine per day. The average wind speed in September is 11 mph (18 km/h), and the humidity level is around 76%.

The water temperature in Harwich in September ranges from 63°F to 70°F (17°C to 21°C). At the beginning of the month, the average temperature is around 70°F (21°C), shifting to 68°F (20°C) by mid-September and reaching 64°F (18°C) in the last ten days. Overall, the average sea temperature in Harwich for September is 68°F (20°C). Very comfortable swimming conditions. The water is fresh but not too cold, and the air temperature is pleasant.

Frequently Asked Questions About Water Temperatures in September in Harwich