Heavy winds and damaging hail are possible in embedded thunderstorms, forecasters say.
Lines of heavy rain with embedded thunderstorms rumbled across Pennsylvania just after dawn this morning as the region will go into a flood watch at 10 o'clock and remain in it throughout the day and well into the night, forecasters say.
Up to a half inch of rain could fall this morning, the National Weather Service was forecasting. There is a potential for damaging winds and hail as a low pressure system takes hold over the area. One to 2 inches of rain are expected today in the Lehigh Valley and northwest New Jersey, with heavier amounts in some places, the weather service said.
Strong thunderstorms that were at 6:30 in the middle of the state were expected to reach the region between 8:15 and 9:15, the weather service said in a short-term forecast. Lightning strikes, power outages and road flooding were possible.
Lehigh County was in a severe thunderstorm watch at 7:30. It was to stay in effect until 11 o'clock. The storms feature winds up to 50 mph and were moving at 55 mph. People were advised to get inside as the storms arrive.
You can watch the weather radar on our AccuWeather page.
There are widespread but minor power outages in the western part of Pennsylvania and a number downed trees, the Associated Press reports. It was dry as the first tee times approached for the U.S. Open at Merion Golf Club in Ardmore, Pa., but an official said they were expecting to suspend play between 8 and 9 o'clock.
Stream and road flooding is expected in Lehigh, Northampton, Warren and Hunterdon counties and some rivers could spill over their banks. At the 5:30 measurement this morning, the Delaware River in Easton was at 8.27 feet, down more than a foot from a day ago, the U.S. Geological Survey reports. It is forecast to crest midday Friday at 18.6 feet, more than three feet below flood stage, the weather service said. Those projections often change during storms and in their aftermath. You can keep track of area rivers and major creeks here.
The Lehigh River in Bethlehem was at 3.4 feet at 5:30, and forecast to crest at 6 a.m. Friday at 8.2 feet, well below its flood stage of 16 feet, the weather service and geological survey said.
The Musconetcong River in Bloomsbury was at 2.71 feet at 5:15. There is no forecast at the moment as to if it will reach its 6-foot flood stage, according to the weather service.
The National Park Service reminds everyone that once the storm passes the rivers will remain very high -- and very dangerous -- for some time.