A coastal storm will pack even more rain than previously predicted, forecasters warn

BETHLEHEM, Pa. — A coastal system is expected to bring heavy rain to the area this weekend, prompting concerns of flooding and power outages.

The National Weather Service now predicts up to 3 inches of rain will fall throughout the day Saturday.

NWS said conditions will deteriorate beginning Friday night, with heavy precipitation and breezy conditions through Saturday night.

The Lehigh Valley is on the western edge of an axis of heavy rainfall and early predictions Thursday were for up to 2 inches of rain expected.

A widespread 2 to 3 inches of rain is likely near and southeast of Interstate 95, also including parts of central and northeastern New Jersey.

“Current guidance continues to support the idea that the greatest axis of rainfall will occur across the coastal plain of southern New Jersey and Delmarva,” the latest forecast discussion said.

Timing, impacts

In his latest video update, EPAWA meteorologist Bobby Martrich said, “this one has a lot of potential to produce heavy rain.”

But timing on the start and end of the storm still is a question.

“I’m thinking it’s going to be ending actually late Saturday afternoon, as opposed to evening, but we’ll fine-tune that as we get closer,” Martrich said.

The greatest concern for potential flooding resides where the heaviest rainfall axis is forecast, but other areas could experience minor flooding given the excessive amount of rainfall expected.

The Weather Prediction Center has much of the coastal plain in a slight risk area for excessive rainfall — “the type of heavy rainfall that may lead to standing flood waters in flat, low-lying areas,” the weather service said.

Minor poor drainage flooding in urbanized areas also can be expected, along with flooding of creeks and streams.

With windy conditions expected to develop late Saturday into Saturday night, power outages also will be a concern.

“We are going to have to send alerts for this, there’s no doubt,” Martrich said.

Temperatures

Temperatures are expected to remain relatively mild, in the upper 40s to near 50 degrees.

But as a cool and dry airmass begins to push into the region Saturday night, it will drop temperatures well into the 30s and upper 20s, the weather service said.

"Resulting wind chills will be near 20 degrees across much of the area, and in the single digits across the southern Poconos."