The flood watch issued by the National Weather Service (NWS) for our area and beyond from Wednesday afternoon through Thursday afternoon is being caused by a combination of melting snow and what weather forecasters fear are periods of heavy rain, or even thunderstorms.
“Starting Wednesday morning into the evening, we could see rainfall amounts of 3/4 to 1-1/2 inches, or even higher amounts if thunderstorms occur,” said a National Weather service meteorologist in Mount Holly, N.J. “That could directly lead to flooding.”
Melting snow from Winter Storm Jonas is a also a worry for weather watchers.
“Our main concern is the snow melt, even in areas that have recently lost substantial snow pack, because that means the ground is still saturated with water. Further north, there are areas with considerable snow pack remaining as of Tuesday afternoon,” added the NWS spokesperson.
The good news? The Delaware River looks tame, according to current projections. The water level at the NewHope-Lambertville free bridge currently stands at around 1 foot — flood stage occurs at 13 feet. The Delaware River is expected to crest at 5.8 feet on Thursday afternoon.
“We’re not expecting problems with Delaware River levels, however a primary concern is the smaller creeks and streams, along with low-lying areas and those with poor drainage or large impermeable spaces like Philadelphia and some suburbs.
“We’re also watching levels in the Schuylkill River,” continued the NWS meteorologist. “And we’re watching the Raritan and Passaic Basins…they could get close to flood stage.”
Ultimately, the extent of flooding will depend on Wednesday’s rain, but there is little doubt that there will be little snow if any to be seen by Thursday morning, says the NWS.
They advise folks living in areas prone to flooding to stay alert for warnings and be prepared to take evasive action if needed.