Summer Nor'easter: Storm Will Pound East Coast With Heavy Rain

A rare summer nor'easter will leave much of the East Coast drenched over the weekend as a storm, which weather forecasters say is more typical for the fall, will form over the Mid-Atlantic Friday into Saturday.

The National Weather Service says the system is currently in a formative stage across the Ohio Valley as a couple of low pressure waves ride along a cold front. The NWS says that once this cooler air mass behind the cold front continues to move into the northern United States, an upper-level trough that forecasters say is expected to form over the Great Lakes will interact with the low pressure waves. Government forecasters say that this will intensify a low pressure system over the mid-Atlantic late Friday into Saturday.

The system is expected to have some similarities to a "cool season" nor'easter.

Heavy rain is expected to start Friday night and people can also expect gusty winds, which will be especially prevalent along the coast. The NWS says there's a potential for about two to five inches of rain from the central Appalachians moving east to the northern mid-Atlantic coast through Saturday. Flash flooding is also possible for areas that have repeated thunderstorm activity.

As a result of the storm, temperatures will be cooler than average for a few days, the NWS says.

Scattered showers and thunderstorms will also affect parts of the desert southwest, the four corner, parts of the Rockies and the central High Plains. Eastern Colorado and northern New Mexico will see the most amount of rainfall, the NWS says.

The Capital Weather Gang at The Washington Post notes that though the storm is more typical for the winter, the storm will be able to generate significantly more precipitation than a winter storm because the summer air is much more humid. The Post notes that the storm is also expected to be slow-moving.

Warnings and watches have already been issued by local weather authorities in areas where the storm is expected to hit. New York City is under a "hazardous weather outlook" as heavy rain that is expected to drench Long Island on Friday and Saturday could end up slamming the city as well. For the Washington D.C. region, officials have issued a flash flood watch.

Patch will update this post with the latest on the nor'easter.

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