New York City and Philadelphia Face Life-Threatening Flash Flood Threat From Severe Storms

A dangerous storm system is bringing the threat of life-threatening flash flooding across parts of the Northeast, including New York City and Philadelphia.

More than 40 million people are under flood watches as forecasters warn the storm could produce several inches of rain and overwhelm drainage systems in some urban areas.

The storm is expected to bring widespread rainfall totals of 2 to 5 inches, with some areas potentially seeing higher amounts. Forecasters say parts of northern New Jersey, northeastern Pennsylvania, the Lower Hudson Valley, and western New England are among the areas at greatest risk.

Officials are warning that intense rainfall rates could create dangerous conditions, especially in heavily populated areas where stormwater systems can quickly become overwhelmed.

New York City can typically handle rainfall rates up to about 1.75 inches per hour, but forecasters say storms producing heavier rates can quickly lead to flooded streets, transportation disruptions, and dangerous travel conditions.

The storm system already caused flooding in parts of Pennsylvania and New Jersey, where some roadways were closed and water rescues were reported.

Meteorologists say the storm is unusual for late July because of its strength and the amount of moisture it is carrying. Warmer temperatures allow the atmosphere to hold more water, increasing the potential for intense downpours.

The heaviest rain for the New York City and Philadelphia areas is expected Tuesday afternoon through overnight, with additional flooding concerns moving into parts of New England on Wednesday.

Officials are urging residents to avoid flooded roads, monitor weather alerts, and use caution while traveling as the storm moves through the region.

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