Tropical Storm Fay brings drenching rainfall to U.S. Northeast

NEW YORK (Reuters) - Freshly formed Tropical Storm Fay is expected to sweep across the heavily populated northeastern United States on Friday, bringing moderate to heavy rains and the potential for some flooding, the National Weather Service said.

The weather system reached tropical storm strength on Thursday afternoon with sustained winds of 40 mph (64 kph) after developing over Cape Hatteras, North Carolina.

The storm started to drench several Mid-Atlantic states even before making landfall, the service said.

“The main impact is not going to be the wind," meteorologist Laura Pagano said by phone from the service's Weather Prediction Center in College Park, Maryland. "It's actually going to be associated with the rainfall.”

Two to four inches (5 to 10 cm) of rain were expected through most coastal areas of Delaware, Maryland, New Jersey and eastern Pennsylvania, Pagano said as the storm moved into the New York City area early Friday afternoon.

Winds are expected to diminish as the storm comes ashore, especially when it reaches New York's Hudson River Valley, Connecticut and Western Massachusetts on Saturday, but there will be a risk of localized flash flooding, she said.

“This is going to be ongoing... through the daytime today and into the overnight hours as it continues to progress north,” she said. "The overall extent of damage should not be exceptionally widespread."

The storm prompted the White House to postpone a campaign rally that President Donald Trump had planned to hold in Portsmouth, New Hampshire, on Saturday night. The event will take place in "a week or two," the White House said.

But while the storm is expected to bring rain and gusty winds to southern New Hampshire early on Saturday, it will have weakened and moved out of the area by the afternoon, National Weather Service meteorologist Dan Petersen said.

(Reporting by Peter Szekely; Editing by Dan Grebler and Aurora Ellis)