Boston has a humid continental climate. Summers are typically hot, rainy, and humid, while winters are cold and oscillate between periods of rain and snow. Spring and fall are usually mild, with varying conditions dependent on wind direction and jet stream positioning. Prevailing wind patterns that blow offshore minimize the influence of the Atlantic Ocean.
Boston’s coastal location on the North Atlantic moderates its temperature, but makes the city very prone to Nor’easter weather systems that can produce much snow and rain. Snowfall increases dramatically as one goes inland away from the city (especially north and west of the city)—away from the moderating influence of the ocean. There is also high year-to-year variability in snowfall.
Fog is fairly common, particularly in spring and early summer, and the occasional tropical storm or hurricane can threaten the region, especially in late summer and early autumn. Due to its situation along the North Atlantic, the city often receives sea breezes, especially in the late spring, when water temperatures are still quite cold and temperatures at the coast can be more than 20 °F colder than a few miles inland, sometimes dropping by that amount near midday. Thunderstorms occur from May to September, that are occasionally severe with large hail, damaging winds and heavy downpours. Although downtown Boston has never been struck by a violent tornado, the city itself has experienced many tornado warnings. Damaging storms are more common to areas north, west, and northwest of the city. Boston has a relatively sunny climate for a coastal city at its latitude.