Lakeshore Flood — Northern Erie, New York

2019-10-31 · Northern Erie, New York

Wider weather episode

A deepening area of consolidated low pressure tracked from the north shoreline of Lake Erie to Toronto, and then along the northern shoreline of Lake Ontario Thursday evening, October 31st. This system brought recorded breaking Halloween rains to our region, damaging wind gusts, a large Lake Erie seiche, a smaller Lake Ontario seiche, and river flooding in the North Country (Cayuga, Black and Moose River). Southwest winds increased dramatically on Halloween evening following a cold frontal passage. Immediately behind the front, winds were southwest and channeled across the typical locations northeast of Lake Erie from Dunkirk to the Niagara Frontier and eastward to Rochester. Southwest wind gusts were 45 to 50 mph. Potential vorticity analysis of this system was impressive, with the 1.5 PVU surface descending to below 700 hPa. This suggested a tropopause fold and intrusion of stratospheric air into the troposphere, which enhanced lapse rates and mixing potential. Furthermore, a fairly impressive isallobaric fall/rise couplet clipped the Niagara Frontier and then the Saint Lawrence Valley. With 75 knots of flow off the ground and mixing from the tropopause fold crossing the area, a secondary wind maxima to this wind event occurred overnight Thursday and into Friday with warning criteria winds. Thousands of power outages occurred across the area, and pervasive wind-related damage closed hundreds of roads and did countless tree damage across a vast swath of the area. A seiche occurred on Lake Erie, with water rising to just over 9 feet above low water datum just past 8 pm at Buffalo. A second push brought the lake up to 10.67 feet above low water datum with the tropopause fold induced winds. Lakeshore flooding inundated Canalside in Donwtown Buffalo, portions of Grand Island, Hoover Beach in Hamburg, and caused over $5.5 million in damage to homes and property in Erie County alone. Substantial damage was done to the Buffalo breakwall as well as continued destruction of the Dunkirk breakwater from the previous high water event on the lake from October 27. Enough damage was done across New York to have a Presidential Disaster Declaration. Heavy rain also brought flooding concerns. All three climate stations broke their daily October 31 records with 1 to 3 inches of rain falling across the CWA. High winds and lakeshore flooding continued into November 1.

Source: NOAA Storm Events Database, event_id 861210. Narrative written by the NWS forecast office that issued the report.