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Flash Flood in Mercer County, New Jersey

Flash Flood September 1, 2021 – September 2, 2021 · Mercer County, New Jersey

Deaths

$50.0M

Damage as recorded

$1.0M

Crop damage

Where the report was made, with tornadoes recorded within 15 miles over the years.

What the National Weather Service wrote

Widespread flash flooding occurred in Mercer County with numerous road closures and nearly 100 water rescues. There were two flood related fatalities in the county, both in Hopewell Township. Many waterways overflowed their banks including the Assunpink Creek, Stony Brook and the Delaware River (with a highly unusual quick response to the runoff).

The wider storm

Post Tropical Cyclone Ida brought heavy rain to New Jersey on September 1. Rainfall totals were as high as 5 to 10 inches. The heavy rain caused significant flash flooding, mainly in the northern half of the state. It resulted in widespread property damage. There were several fatalities.

Began near Titusville (40.3319, -74.9101).

Source: NOAA Storm Events Database, event 985743. Narratives are written by the National Weather Service forecast office that issued the report.

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