Tropical Storm — Northern Nassau, New York

2021-07-09 · Northern Nassau, New York

Event narrative

A mesonet station at Bayville NY recorded a maximum sustained wind of 46 mph and 53 mph gust at 1201 pm LST. Peak winds generally ranged from 30 to 35 mph with gusts to 40 mph across the area. These winds combined with saturated grounds resulted in widely scattered downed trees and power outages. Multiple trees were reported down on the Long Island Railroad Oyster Bay Branch in Oyster Bay NY at 812 am LST, resulting in train service on the line being suspended. In addition, a large tree was downed on a property on Herbert Drive in New Hyde Park at 935 am LST.

Wider weather episode

Tropical Storm Elsa with maximum sustained winds of 65 mph, made landfall as a strong tropical storm on the panhandle of Florida on the morning of July 7th. It weakened to a minimal tropical storm as it tracked into Georgia, and then tracked northeast along the coastal plain through July 8th. Elsa strengthened a bit, with sustained winds of 50 mph, before it emerged off the Delaware coast early the morning of July 9th, and then later that morning tracked across eastern Long Island.

The highest sustained winds were generally 40 to 45 mph along the immediate coast of central and eastern Long Island with a maximum sustained wind of 55 mph at an elevated weather station at Eatons Neck on the north shore of Central Long Island. Peak gusts were generally 40 to 50 mph, with Eatons Neck once again recording the highest gust at 59mph. Away from the shoreline, maximum sustained winds generally ranged from 30 to 35 mph across Long Island and coastal Connecticut.

Wind damage and coastal impacts were minimal from Elsa. Heavy rainfall and flash flooding were the main impacts. A predecessor rainfall event the afternoon and evening of Thursday, July 8, resulted in flash flooding across portions of the area as moisture streaming northward ahead of Tropical Storm Elsa encountered a stationary boundary draped across the area. Rainfall amounts ranged 2-4 inches across portions of Manhattan, the Bronx, and Westchester County, with lesser amounts elsewhere. Tropical Storm Elsa then tracked across eastern Long Island the next morning, July 9, with heavy rainfall north and west of the storm's center, resulting in flash flooding across portions of Long Island and the Lower Hudson Valley. Rainfall totals ranged from 1 1/2-4 inches, highest across Long Island.

Source: NOAA Storm Events Database, event_id 977731. Narrative written by the NWS forecast office that issued the report.