Heavy rain will cause widespread flooding across the area starting Thursday morning. Flood warnings are being issued including a low-lying area warning in Philly. The warnings could remain in effect until Saturday morning, depending on the location and river size.
Steady, light-to-moderate rain has already developed across the region. Most streets and very small creeks will begin to flood during this time period.
Do not attempt to drive or walk through flooded roadways since it is impossible to determine how deep flood waters are and cars can get swept away in as little as one foot of water.
If the rain lightens up a bit or stops briefly, then streets and small creeks may have a chance to drain.
There may be a break from the steady rain ahead of line of heavy rain and thunderstorms that will move through the area.
Expect to see more street flooding with this heavy rain and some of the larger creeks and streams will also begin to rise:
- Neshaminy Creek at Langhorne, Pa.
- Brandywine Creek at Chadds Ford, Pa.
- Perkiomen Creek at Graterford, Pa.
- North Branck of the Rancocas Creek at Pemberton, N.J.
Although they will be rising, many of the larger creeks are not expected to rise above flood stage until Friday morning.
The heavy rain will end from west to east around midnight.
Aside from a few passing showers, the steady rain should end early Friday. Many roads and small streams that have been flooded should improve, but larger creeks are expected to rise above flood stage. Many areas will see minor to moderate flooding according to the river gauge forecasts.
The larger rivers will continue rise any may also be above flood stage. The portion of the Delaware River that are affected by the tides could also flood with the high tide early Friday. That includes areas along the river in the following counties:
- Gloucester County, N.J.
- Camden County, N.J.
- Burlington County, N.J.
- Delaware County, Pa.
- Philadelphia County, Pa.
No rain is expected but the Schuylkill and Delaware Rivers remain above flood stage.
Both should crest by early Saturday and begin to fall. They may not be below flood stage again until Late Saturday or early Sunday.