A strong upper-level trough over the Great Lakes  was headed towards the Northeast on Friday, August 4th along with a weak cold front.  Much of eastern New York was situated with a warm and humid air mass, allowing for the atmosphere to be rather unstable.
Strong to severe thunderstorms developed north and west of the Capital District during the afternoon hours. The leading cell in this activity was particularly strong and produced a couple reports of wind damage and one report of large hail. This storm eventually produced a weak, brief tornado on Great Sacandaga Lake captured by amateur video. Additional severe thunderstorm development resulted in reports of wind damage across the Western Adirondacks and Lake George-Saratoga Regions.
A line of storms also approached from central New York later in the evening. These storms resulted in additional reports of trees and wires down.
As a result of the storms throughout the day, over 40,000 customers lost power across the region.

Flash Flood in FULTON, NEW YORK
From 04-AUG-17 15:50:00 to 04-AUG-17 17:21:00 (EST-5)
Location: JACKSON SUMMIT
Flood cause: Heavy Rain
Property damage: 1.00K
Crop damage: 1.00K
Reported by: State Official

Gray Road in the town of Mayfield washed out due to heavy rain. This was reported by the Fulton County Sheriffs Office.

Funnel Cloud in FULTON, NEW YORK
From 04-AUG-17 13:45:00 to 04-AUG-17 13:46:00 (EST-5)
Location: CRANBERRY CREEK
Reported by: Broadcast Media

A funnel cloud was observed over Great Sacandaga Lake and was confirmed by video.

Hail in FULTON, NEW YORK
From 04-AUG-17 13:00:00 to 04-AUG-17 13:01:00 (EST-5)
Location: CORK
Magnitude: 1.00 
Reported by: NWS Employee

One inch hail was reported by an NWS Employee.

Tornado in SARATOGA, NEW YORK
From 04-AUG-17 13:50:00 to 04-AUG-17 13:51:00 (EST-5)
Location: FAYVILLE
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A video captured a tornado briefly touching down over Great Sacandaga Lake. The tornado caused no damage from which the NWS could assign an EF-scale rating. The estimated path length was 100 yards with a path width of 20 yards.

Thunderstorm Wind in FULTON, NEW YORK
From 04-AUG-17 13:10:00 to 04-AUG-17 13:10:00 (EST-5)
Location: GLOVERSVILLE
Magnitude: 50.00 EG
Reported by: 911 Call Center

Trees and wires were reported down.

Thunderstorm Wind in ULSTER, NEW YORK
From 04-AUG-17 14:09:00 to 04-AUG-17 14:09:00 (EST-5)
Location: LAKE KATRINE
Magnitude: 50.00 EG
Reported by: Trained Spotter

Two large limbs were downed about 1 foot in diameter at Route 9W and Boices Lane.

Thunderstorm Wind in FULTON, NEW YORK
From 04-AUG-17 14:54:00 to 04-AUG-17 14:54:00 (EST-5)
Location: NORTHVILLE
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was down on Ridge Road in the town of Northville. This was reported by the Fulton County Sheriffs Office.

Thunderstorm Wind in HERKIMER, NEW YORK
From 04-AUG-17 15:12:00 to 04-AUG-17 15:12:00 (EST-5)
Location: BURRELL CORNERS
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was reported down.

Thunderstorm Wind in HERKIMER, NEW YORK
From 04-AUG-17 15:24:00 to 04-AUG-17 15:24:00 (EST-5)
Location: SALISBURY
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was reported down.

Thunderstorm Wind in HERKIMER, NEW YORK
From 04-AUG-17 15:25:00 to 04-AUG-17 15:25:00 (EST-5)
Location: BURRELL CORNERS
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was downed.

Thunderstorm Wind in HERKIMER, NEW YORK
From 04-AUG-17 15:28:00 to 04-AUG-17 15:28:00 (EST-5)
Location: SALISBURY CENTER
Magnitude: 50.00 EG
Reported by: Trained Spotter

A trained spotter reported wires down on Barnes Road.

Thunderstorm Wind in WARREN, NEW YORK
From 04-AUG-17 15:28:00 to 04-AUG-17 15:28:00 (EST-5)
Location: HARTMAN
Magnitude: 50.00 EG
Reported by: 911 Call Center

Trees and wires were downed.

Thunderstorm Wind in WARREN, NEW YORK
From 04-AUG-17 15:29:00 to 04-AUG-17 15:29:00 (EST-5)
Location: HARTMAN
Magnitude: 50.00 EG
Reported by: 911 Call Center

Trees were reported down on roadway.

Thunderstorm Wind in WARREN, NEW YORK
From 04-AUG-17 16:06:00 to 04-AUG-17 16:06:00 (EST-5)
Location: GLENS FALLS
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was down blocking a roadway.

Thunderstorm Wind in WARREN, NEW YORK
From 04-AUG-17 16:06:00 to 04-AUG-17 16:06:00 (EST-5)
Location: WEST GLEN FALLS
Magnitude: 50.00 EG
Reported by: Broadcast Media

A tree fell on a house.

Thunderstorm Wind in WARREN, NEW YORK
From 04-AUG-17 16:07:00 to 04-AUG-17 16:07:00 (EST-5)
Location: WEST GLEN FALLS
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was downed.

Thunderstorm Wind in WARREN, NEW YORK
From 04-AUG-17 16:09:00 to 04-AUG-17 16:09:00 (EST-5)
Location: GLENS FALLS
Magnitude: 50.00 EG
Reported by: 911 Call Center

Trees and wires were downed in front of a house.

Thunderstorm Wind in WARREN, NEW YORK
From 04-AUG-17 16:10:00 to 04-AUG-17 16:10:00 (EST-5)
Location: WEST GLEN FALLS
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was downed onto a house.

Thunderstorm Wind in WARREN, NEW YORK
From 04-AUG-17 16:11:00 to 04-AUG-17 16:11:00 (EST-5)
Location: GLENS FALLS
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was leaning on wires.

Thunderstorm Wind in WARREN, NEW YORK
From 04-AUG-17 16:15:00 to 04-AUG-17 16:15:00 (EST-5)
Location: FRENCH MTN
Magnitude: 50.00 EG
Reported by: NWS Employee

Large tree branches were down near Six Flags Great Escape.

Thunderstorm Wind in HAMILTON, NEW YORK
From 04-AUG-17 16:50:00 to 04-AUG-17 16:50:00 (EST-5)
Location: DEERLAND
Magnitude: 50.00 EG
Reported by: 911 Call Center

Trees were downed on North Point Road near Long Lake.

Thunderstorm Wind in WARREN, NEW YORK
From 04-AUG-17 16:51:00 to 04-AUG-17 16:51:00 (EST-5)
Location: GLENS FALLS
Magnitude: 50.00 EG
Reported by: 911 Call Center

Trees and wires were downed.

Thunderstorm Wind in HERKIMER, NEW YORK
From 04-AUG-17 17:28:00 to 04-AUG-17 17:28:00 (EST-5)
Location: NORTH WINFIELD
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was downed.

Thunderstorm Wind in HERKIMER, NEW YORK
From 04-AUG-17 17:43:00 to 04-AUG-17 17:43:00 (EST-5)
Location: MOHAWK
Magnitude: 50.00 EG
Reported by: Trained Spotter

Wires were downed on South Caroline Street.

Thunderstorm Wind in HAMILTON, NEW YORK
From 04-AUG-17 17:44:00 to 04-AUG-17 17:44:00 (EST-5)
Location: RAQUETTE LAKE
Magnitude: 50.00 EG
Reported by: 911 Call Center

Trees and wires reported down.

Thunderstorm Wind in HERKIMER, NEW YORK
From 04-AUG-17 17:45:00 to 04-AUG-17 17:45:00 (EST-5)
Location: MOHAWK
Magnitude: 50.00 EG
Reported by: 911 Call Center

Trees and wires were downed.

Thunderstorm Wind in HERKIMER, NEW YORK
From 04-AUG-17 18:09:00 to 04-AUG-17 18:09:00 (EST-5)
Location: OHIO
Magnitude: 50.00 EG
Reported by: 911 Call Center

Trees and wires were downed.

Thunderstorm Wind in WARREN, NEW YORK
From 04-AUG-17 18:54:00 to 04-AUG-17 18:54:00 (EST-5)
Location: GLENS FALLS
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was leaning on wires.

Thunderstorm Wind in FULTON, NEW YORK
From 04-AUG-17 12:15:00 to 04-AUG-17 12:15:00 (EST-5)
Location: EPHRATAH
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was down on Mud Road. This was reported by the Fulton County Sheriff's Office.