Today should be mostly clear and warm, with a high temperature near 80°F — time to install air conditioning! After today, the air will remain humid as the weather takes a turn for the worse. Expect rain showers and thunderstorms on Saturday, ahead of a cold front that will move in Saturday night. Sunday will be cooler and cloudy, with some rain possible. Such weather is not confined to New England; forecasts predict precipitation in 47 of the continental U.S. states in the next 36 hours.