The highest day temperature in July 2025 was 81°F. The lowest night temperature was 68°F. The average values for day and night temperatures during July were 74.7°F и 72.5°F respectivly.

The average sea surface temperature in July 2025 for Charlestown was 71.3°F. The maximum and minimum values were 67.4°F and 74.2°F respectively.

You can expect various weather conditions during July. Be ready for sunny, cloudy or even gloomy days.

Precipitation total in July for Charlestown is 1.0 in. It makes july one of the least rainy months of the year.

The average wind speed in July is 8.8 mph. It makes July the most windless month of the year for Charlestown.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for Charlestown in July is 7.8 hours.