Coastal Flood — Coastal Rockingham, New Hampshire

2020-09-22 · Coastal Rockingham, New Hampshire

Event narrative

In Hampton, the astronomical tide was 10.1 feet with a storm surge of 1.5 feet at high tide to reach an 11.6 foot storm tide. Flood stage in Hampton is 11.0 feet (MLLW). Although winds were offshore, large, long period swell entered the Gulf of Maine leading to splash-over along the seacoast of New Hampshire. Nearshore waves increased to 10 feet every 16 seconds at high tide. Significant splash-over flooded roadways with seawater in Seabrook and along route 1A in Hampton.

Wider weather episode

Hurricane Teddy underwent extra-tropical transition to a strong 951 mb storm well off shore in the Gulf of Maine before moving north north towards Halifax, Nova Scotia. This powerful cyclone coincided with astronomically high tides. Although winds were offshore, large, long period swell entered the Gulf of Maine leading to splash-over and minor coastal flooding to coastal New Hampshire.

Source: NOAA Storm Events Database, event_id 922439. Narrative written by the NWS forecast office that issued the report.