On April 1, 2017, a Nor'easter hit New England, covering the region with snow.
A Nor'easter forms when warm, moist air traveling north with the Gulf Stream
collides with cold air moving down from Canada, resulting in snow and rain.
The Global Precipitation Measurement (GPM) mission observed the storm, which dumped
8 - 14 inches of snow over southern Maine and New Hampshire.
GPM's radar detected the storm's front as a deep layer of rain that abruptly ended south of
Cape Cod.
This suggested a strong temperature gradient in the lower atmosphere,
which is a key ingredient for strengthening the storm.