A series of cold front moved towards the region on Thursday, September 12th.  Despite some periods of cloudiness, a warm and humid air mass ahead of the approaching boundaries allowed for moderate amounts of instability to be in place.  Along and ahead of the boundaries, several lines of showers and thunderstorms developed and moved across the region during the afternoon and early evening hours.  In addition to a large amount of cloud to ground lightning, a few of the thunderstorms became severe, with damaging wind gusts.  Several trees were downed across the region.  Up to 4,600 people were without power at one point in the Capital Region due to the thunderstorms.
Some areas that received repeated showers and thunderstorms experienced flash flooding as well, with roads closed as a result.  The flooding even caused an evacuation of a senior hosing complex in Nassau.  Two to four inches of rain in a short period of time was reported in the areas that experienced flash flooding.
As the last in the series of cold fronts crossed during the evening hours, the threat for showers and thunderstorms ended.

Flash Flood in ALBANY, NEW YORK
From 12-SEP-13 14:00:00 to 12-SEP-13 16:00:00 (EST-5)
Location: COHOES
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Heavy rainfall led to flash flooding at the intersection of Canvass and Oneida Streets in Cohoes. Two to three feet of standing water was ponded in the intersection of the road.

Flash Flood in ALBANY, NEW YORK
From 12-SEP-13 14:00:00 to 12-SEP-13 17:00:00 (EST-5)
Location: LATHAM
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

A large stretch of U.S. Route 9 from Erin Street to State Route 155 was closed as a result of flash flooding.

Thunderstorm Wind in RENSSELAER, NEW YORK
From 12-SEP-13 14:10:00 to 12-SEP-13 14:10:00 (EST-5)
Location: HOOSICK FALLS
Magnitude: 50.00 EG
Reported by: Trained Spotter

Trees were reported down on Fairbanks Road and Congress Street in Hoosick Falls as a result of thunderstorm winds.

Flash Flood in RENSSELAER, NEW YORK
From 12-SEP-13 17:50:00 to 12-SEP-13 19:42:00 (EST-5)
Location: NASSAU
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The Kinderhook Creek overflowed its banks and flooded Chatham Street in Nassau.  The water also rose and affected a senior housing complex, which prompted an evacuation of the building.

Flash Flood in RENSSELAER, NEW YORK
From 12-SEP-13 17:50:00 to 12-SEP-13 19:42:00 (EST-5)
Location: SOUTH SCHODACK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Flash flooding occurred on Route 9 in South Schodack as a result of heavy rainfall.

Thunderstorm Wind in ULSTER, NEW YORK
From 12-SEP-13 15:32:00 to 12-SEP-13 15:32:00 (EST-5)
Location: ATWOOD
Magnitude: 50.00 EG
Reported by: 911 Call Center

Trees and wires were reported down throughout Ulster County as a result of thunderstorm winds.

Flash Flood in COLUMBIA, NEW YORK
From 12-SEP-13 17:45:00 to 12-SEP-13 19:42:00 (EST-5)
Location: STUYVESANT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Flash flooding and a mudslide occurred on Route 9J, just south of the intersection with Route 26A, in Stuyvesant, as a result of heavy rain.

Thunderstorm Wind in SCHENECTADY, NEW YORK
From 12-SEP-13 12:35:00 to 12-SEP-13 12:36:00 (EST-5)
Location: AQUEDUCT
Magnitude: 50.00 EG
Reported by: Broadcast Media

A large tree was downed and landed on a deck on Dean Street in Old Niskayuna as a result of thunderstorm winds. Another small tree and some branches were reported down on Mohawk Trail in Niskayuna.

Thunderstorm Wind in RENSSELAER, NEW YORK
From 12-SEP-13 15:03:00 to 12-SEP-13 15:03:00 (EST-5)
Location: VALLEY FALLS
Magnitude: 50.00 EG
Reported by: Broadcast Media

Trees and wires were reported down on Master Street, one mile north of the village of Valley Falls in the town of Schaghticoke, as a result of thunderstorm winds.

Thunderstorm Wind in RENSSELAER, NEW YORK
From 12-SEP-13 13:45:00 to 12-SEP-13 13:45:00 (EST-5)
Location: BRUNSWICK CENTER
Magnitude: 50.00 EG
Reported by: Broadcast Media

A large tree was downed on Hoosic Road in Brunswick as a result of thunderstorm winds.