Manhattan has a humid continental climate resulting from prevailing wind patterns that bring cool air from the interior of the North American continent. New York winters are typically cold and can be snowy. Snowfall varies from year to year, but usually averages about 2 feet (60 cm) in total. The Atlantic Ocean helps keep temperatures warmer in the city than in the interior Northeast, however, there has never been a winter since records began in 1869 in which enough snow to cover the ground did not fall at least once.