Weather Facts

What is the Bermuda High?

The Bermuda High is a high pressure area that is usually centered in the vicinity of Bermuda during the spring and summer. This high pressure area is responsible for the prolonged heat waves in the Eastern part of the country. Since winds blow clockwise around high pressure areas in the northern hemisphere, a south to south-westerly wind transports heat and humidity into the Mid-Atlantic States. During the late spring and summer, cold fronts from the north and west have trouble making inroads into the Hampton Roads area due to the persistent Bermuda Highís influence. The high migrates east and west which causes fluctuations in our weather. There are times when it builds westward and is configured in such a way to change our winds to a south-southeasterly direction. This sometimes brings in a tropical air mass and lots of moisture. The interaction of the warm moist air moving over the land causes shower and thunderstorms that can dump copious amounts of rain. Two factors cause the air to rise. The friction of the land and the heat from the land causes the air to rise high into the atmosphere, This causes condensation which then leads to showers and thunderstorms. The position of the Bermuda High also is a player in steering tropical cyclones towards the west and then northwest. If the high is further out in the Atlantic, the odds are that the cyclones will curve and go out to sea. If the high is further west, there is a good chance that the cyclones can impact the East or Gulf Coasts of the United States.