Flood threat in context

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Flooding from Irene in 2011; some stream flooding in the Philadelphia region is likely the next few days. (Alejandro A. Alvarez/Staff)

The area-wide flood watch remains in effect through Thursday morning with from 3 to as much as 5 inches of rain expected.

Based on forecast rainfall amounts, the National Weather Service says minor flooding along streams is likely and  moderate to major flooding is at least possible.

Rises are anticipated on the major rivers, but any significant flooding on the Delaware River and Schuylkill is unlikely. Of course that could change.

But the region has a few things going for it in terms of avoiding catastrophic flooding.

For one thing, rainfall for April has been well below normal, and the awakening plant life is primed to take a stiff drink or two.

And thanks to the recent dryness, rivers and streams are quite low.

For example, the Delaware River at Trenton stood at 9.2 feet at midmorning; flood stage is 20 feet.

The gage on the Schuylkill at Norristown was reading about 8.5 feet; flood stage is 17. The Chester Creek was down to 2.9 feet, better than 6 feet below flood stage.

Still, that’s a ton of rain in the forecast, about a month’s worth. The heaviest rain is due late tonight and is expected to continue into Wednesday night.

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