A healthy upper level trough and frontal boundary moved from Ontario into northern NY during the evening and overnight hours of July 20th. Ahead of this system, a vigorous squall line of thunderstorms that developed in Ontario during the early afternoon hours moved across northern NY from mid-afternoon into the evening hours with numerous reports of damaging winds.

Thunderstorm Wind in ST. LAWRENCE, NEW YORK
From 20-JUL-21 15:23:00 to 20-JUL-21 15:23:00 (EST-5)
Location: OGDENSBURG INTL ARPT
Magnitude: 55.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

A 63 mph wind gust was recorded at the KOGS AWOS site. Numerous trees and power lines down across town.

Thunderstorm Wind in ST. LAWRENCE, NEW YORK
From 20-JUL-21 15:40:00 to 20-JUL-21 15:40:00 (EST-5)
Location: WADDINGTON
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Boat flipped and trees/branches down.

Thunderstorm Wind in ST. LAWRENCE, NEW YORK
From 20-JUL-21 15:32:00 to 20-JUL-21 15:32:00 (EST-5)
Location: LISBON
Magnitude: 55.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Public

Numerous trees and utility lines downed by thunderstorm winds.

Thunderstorm Wind in ST. LAWRENCE, NEW YORK
From 20-JUL-21 15:35:00 to 20-JUL-21 15:35:00 (EST-5)
Location: HEUVELTON
Magnitude: 52.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Public

Numerous trees downed by thunderstorm winds.

Thunderstorm Wind in ST. LAWRENCE, NEW YORK
From 20-JUL-21 15:48:00 to 20-JUL-21 15:50:00 (EST-5)
Location: CANTON
Magnitude: 52.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Several trees downed by thunderstorm winds.

Thunderstorm Wind in ST. LAWRENCE, NEW YORK
From 20-JUL-21 15:55:00 to 20-JUL-21 15:57:00 (EST-5)
Location: POTSDAM
Magnitude: 55.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Public

Numerous trees and utility lines downed by thunderstorm winds.

Thunderstorm Wind in ST. LAWRENCE, NEW YORK
From 20-JUL-21 15:55:00 to 20-JUL-21 15:57:00 (EST-5)
Location: NORWOOD
Magnitude: 55.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Numerous trees and utility lines downed by thunderstorm winds.

Thunderstorm Wind in ST. LAWRENCE, NEW YORK
From 20-JUL-21 16:05:00 to 20-JUL-21 16:05:00 (EST-5)
Location: SOUTH COLTON
Magnitude: 50.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

One large tree and numerous small trees downed by thunderstorm winds.

Thunderstorm Wind in ST. LAWRENCE, NEW YORK
From 20-JUL-21 16:41:00 to 20-JUL-21 16:43:00 (EST-5)
Location: WINTHROP
Magnitude: 50.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Public

Tree and branches down on utility lines.

Funnel Cloud in ST. LAWRENCE, NEW YORK
From 20-JUL-21 16:18:00 to 20-JUL-21 16:18:00 (EST-5)
Location: HELENA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Video report of funnel well above tree-line. After investigation, no reports of any tree, ground surface damage.

Thunderstorm Wind in FRANKLIN, NEW YORK
From 20-JUL-21 16:22:00 to 20-JUL-21 16:23:00 (EST-5)
Location: BOMBAY
Magnitude: 55.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Numerous trees and utility lines downed by thunderstorm winds.

Thunderstorm Wind in FRANKLIN, NEW YORK
From 20-JUL-21 16:30:00 to 20-JUL-21 16:32:00 (EST-5)
Location: WESTVILLE CENTER
Magnitude: 61.00 EG
Property damage: 30.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Numerous trees downed by thunderstorm winds along with some minor property damage. NWS storm survey conducted and concluded straight-line winds estimated at 70 mph.

Thunderstorm Wind in FRANKLIN, NEW YORK
From 20-JUL-21 16:37:00 to 20-JUL-21 16:39:00 (EST-5)
Location: CONSTABLE
Magnitude: 55.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Numerous trees and utility lines downed by thunderstorm winds.

Thunderstorm Wind in FRANKLIN, NEW YORK
From 20-JUL-21 16:38:00 to 20-JUL-21 16:39:00 (EST-5)
Location: DUANE CENTER
Magnitude: 55.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Large tree snapped in half with several other trees down.

Thunderstorm Wind in FRANKLIN, NEW YORK
From 20-JUL-21 17:01:00 to 20-JUL-21 17:01:00 (EST-5)
Location: VERMONTVILLE
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Scattered trees down across Vermontville and Bloomingdale.

Thunderstorm Wind in ESSEX, NEW YORK
From 20-JUL-21 17:25:00 to 20-JUL-21 17:26:00 (EST-5)
Location: AUSABLE FORKS
Magnitude: 50.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: State Official

Numerous trees and utility lines downed by thunderstorm winds with arcing lines.

Thunderstorm Wind in CLINTON, NEW YORK
From 20-JUL-21 17:38:00 to 20-JUL-21 17:38:00 (EST-5)
Location: PLATTSBURGH
Magnitude: 50.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Several trees down in the Plattsburgh area.

Thunderstorm Wind in FRANKLIN, NEW YORK
From 20-JUL-21 16:42:00 to 20-JUL-21 16:43:00 (EST-5)
Location: CHATEAUGAY
Magnitude: 55.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Numerous trees and utility lines downed by thunderstorm winds.

Thunderstorm Wind in FRANKLIN, NEW YORK
From 20-JUL-21 16:50:00 to 20-JUL-21 16:51:00 (EST-5)
Location: TUPPER LAKE
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Several trees downed by thunderstorms winds.

Hail in FRANKLIN, NEW YORK
From 20-JUL-21 16:20:00 to 20-JUL-21 16:20:00 (EST-5)
Location: HOGANSBURG
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Hail, slightly larger than a quarter fell.

Thunderstorm Wind in ST. LAWRENCE, NEW YORK
From 20-JUL-21 15:23:00 to 20-JUL-21 15:25:00 (EST-5)
Location: OGDENSBURG INTL ARPT
Magnitude: 55.00 MG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous trees and power lines downed by thunderstorm winds.