HAGERSTOWN — As rain continues to fall over the Tri-State area Thursday morning, a flood warning for areas of Washington, Jefferson and Berkeley counties through Friday night remains in effect.
As of 8:40 a.m. Thursday, 0.60 inches of rain had fallen in Hagerstown since Wednesday, according to Hagerstown weather observer Greg Keefer's website at i4weather.net.
Periods of moderate to heavy rain started Wednesday afternoon and were expected to continue through Thursday night, potentially creating flooding as the storm moves through the Tri-State area.
In the higher elevations, sleet is expected to mix with the heavy rain at times, but no accumulation of sleet is expected, according to the warning.
Flooding in low-lying areas is expected.
"Those living in areas prone to flooding should be prepared to take action, should flooding develop," the weather service said.
The rain is being caused by a strong low-pressure system that is pulling moisture from the Gulf of Mexico, weather service technician Trina Heiser said Wednesday night.
The region is forecast to experience flooding from major waterways, including the Potomac, Shenandoah and Rappahannock rivers starting Friday and into Saturday, the weather service said. Area creeks and streams are also expected to crest their banks.
In Jefferson County, the Potomac River at Harpers Ferry, W.Va., is expected to crest late Friday night, the weather service said in a flood warning issued Wednesday afternoon.
The flood stage at that point is 18.0 feet, and minor flooding is forecast, with the river expected to rise to nearly 20.2 feet by Saturday morning, the weather service said.
At 20.5 feet, the water could begin to flow through the open tunnel between the Potomac River and historic Harpers Ferry. Water could reach the lower edge of town and inundate half of main street and half of the shuttle-bus parking lot, according to the flood warning.
The Potomac River in Harpers Ferry stood at 8.2 feet as of 1 a.m. Thursday, the weather service said.
The Conococheague Creek in Washington County is forecast to rise above its flood stage of 8 feet by early Friday, according to a flood warning issued Wednesday evening.
The creek is expected to rise to nearly 12 feet by Friday afternoon. If the water reaches 11 feet, much of Wishard Road will be flooded, the weather service said.