Increase in extreme precipitation events in the northeastern US over the past 22 years

There has been a 53-percent increase in extreme precipitation events in the northeastern United States since 1996, according to a new peer-reviewed study from Dartmouth College.

Hurricanes and tropical-storm precipitation was the primary cause (48 percent) of this increase in extreme precipitation followed by thunderstorms (25 percent) and extratropical storms (15 percent) such as a nor'easter.

<img src="https://vortex.accuweather.com/adc2004/pub/includes/columns/climatewx/2018/590x442_08010301_columbia_njflood_june06.jpg"/>

Warmer surface waters in the Atlantic Ocean, increasing water vapor and a wavier jet stream pattern are helping to fuel these storms, leading to more intense rainfall.

A total of 88 percent of the increase in extreme precipitation events was caused by large storms during the months of February, March, June, July, September and October.

In order to reach their conclusion, the research team analyzed precipitation data from 1979-2016 across the northeastern U.S. including daily weather maps and ocean/atmospheric fields.