More Severe Weather on the Way
September 8, 2011 • 12:52AM

Even while communities along the Atlantic Coast of the U.S. have not yet recovered from the damage wreaked by Hurricane Irene, Tropical Storm Lee is adding more injury.

Heavy rainfall, predicted through Thursday across the Appalachians and Mid-Atlantic states, is expected to amount to an additional 4 to 8 inches, with up to 10 possible in some areas, according to the National Weather Service. "These rains may cause life-threatening flash floods and mudslides," the NWS warned in a statement on its website.

The areas identified as most at risk for flooding were the Appalachians and interior Northeast, particularly the municipalities of Altoona and Johnstown, Pennsylvania, and Elkins, West Virginia.

Tropical moisture and gusts streaming up from the Atlantic Ocean also threatened to cause tornadoes.

The government of Maryland forecast thunderstorms Wednesday and Thursday, and a flash flood watch was in effect with a coastal flood watch expected in the evening.

Resurging rivers from Northhampton, Massachusetts, to Philadelphia, already filled from Hurricane Irene, flooded their banks and shut down sections of major roadways just before the morning commute on Wednesday morning.

Near New York City alone, authorities said they closed down parts of four separate parkways, and none was expected to open quickly. In Philadelphia, one of the main commuter routes into Center City was closed because of flooding from the Schuylkill River. Amtrak also suspended service on one of the busiest commuter rail lines in the Philadelphia region, the Southeast Pennsylvania Transit Authority line from two suburbs.

Rising waters of a rain-swollen creek forced the evacuation of residents in the northeastern Pennsylvania city of Wilkes-Barre early Wednesday morning, and officials ordered the mandatory evacuation of about 3,000 residents. Rain from Irene had prompted evacuations there two Sundays ago.

The National Weather Service issued flood warnings for parts of the Catskills and the Schoharie Creek valley. Those two eastern New York areas were devastated by Tropical Storm Irene on Aug. 28. There were voluntary evacuations in one town in the Catskills. Some schools in the Hudson Valley closed or delayed their start Wednesday.

In New Jersey, the remnants of Lee were expected to drop anywhere from 2 to 5 inches of rain. Major flooding was forecast on Wednesday for the Passaic River, which breached its banks during Irene and caused serious damage in some communities.

The U.S. has likely escaped Hurricane Katia's path, but current models show the East Coast to be at much higher risk from at least two more developing systems through mid-September.

The next two names on the list of tropical cyclones are Maria and Nate. Each is potentially developing already, and models show each has a shot at impacting the U.S.

One system expected to crank up over the southwestern Gulf of Mexico this week has similarities to Tropical Storm Lee, which drenched the eastern U.S. in the past week while its winds spread wildfires in Texas amid drought conditions. That developing system could move northeasterly by the weekend and into next week, threatening the U.S.

Another system also deserves close watching: Tropical Depression 14 is farther west than Katia currently, but steering upper-level wind flow could bring that system close to or over the southern Atlantic coast by mid- to late September.