From Maine to West Virginia, the Northeast has seen a larger increase in extreme precipitation than anywhere else in the U.S. Prior research found that these heavy rain and snow events, defined as a day with about two inches of precipitation or more, have been 53 percent higher in the Northeast since 1996. A Dartmouth study finds that hurricanes and tropical storms are the primary cause of this increase, followed by thunderstorms along fronts and extratropical cyclones like Nor’easters. The findings are published in the Journal of Geophysical Research.