Full Notification

Two to four inches of rain is currently expected over portions of eastern Pennsylvania, New Jersey, Delaware and Maryland through Friday. Given the expected meteorological conditions, higher amounts are possible, especially north of Philadelphia. Light rain is expected to begin Wednesday evening, becoming heavy Thursday morning and then lasting into Friday morning.
•Moderate to major flooding will be widespread with this rainfall pattern. Record flooding is a possibilitywhere the heaviest rain happens to fall. Why?:
–Rivers are still rising this Tuesday morning in the lower portions of the Passaic River Basin in New Jersey in response to heavy rain on Sunday. Other streams and rivers in the Mount Holly CWA have crested and are falling at this time, but are running higher than normal.
–Soils are saturated in some areas. Even with additional drying between now and Thursday, the rainfall-runoff process will be very efficient with this next event.
–Some reservoirs are expected to spill with precipitation and snowmelt (north) from this upcoming event, including both Pepactonand Cannonsvillein the upper Delaware River Basin.
–Flash flooding, small stream flooding and river flooding can all be expected with this upcoming event, beginning as early as Wednesday night.
•A Flood Watch is already in effect for the northern two-thirds of the NWS Mount Holly CWA.
•Any tidal flooding that does occur should be minor. Heavy rain at the time of local high tide on Thursday and Friday will result in significant ponding.
•Maintain situational awareness by monitoring our website at: http://weather.gov/phi