Coastal Flood — Coastal Rockingham, New Hampshire

2020-09-23 · Coastal Rockingham, New Hampshire

Event narrative

The astronomical tide in Hampton of 9.4 feet combined with minimal storm surge of 0.3 feet at high tide to reach a 9.5 foot storm tide (MLLW) which is short of flood stage inundation impacts. 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 8 feet every 16 seconds at high tide. In Hampton, splash-over flooded portions of Asheworth and adjacent streets due to the large pounding surf and elevated coastal waters.

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 bringing a second day of minor coastal flooding to the New Hampshire Seacoast. 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 922440. Narrative written by the NWS forecast office that issued the report.