New York City flash flood event report

On July 18, 2026, a fast-moving storm dropped intense rainfall across the New York City metro area and the wider Northeast Corridor, triggering flash flooding that disrupted transit, closed major roadways, and brought ground stops at all three of the region's major airports.

Estimated damage to the NYC metro area from this event ranges between $200 million and $610 million in which $70 million and $214 million of damage could have been prevented if people received early alerts and responded to them. This report sets out what happened, what Previsico forecast, and why the difference between a government flood alert and Previsico’s site-specific intelligence matters to the organisations and businesses most exposed to events like this.