A very warm and humid air mass was in place over eastern Upstate New York on Sunday, July 19th with temperatures reaching over 90 degrees in many areas. The warm and humid conditions allowed the atmosphere to become quite unstable.
As a cold front approached from the eastern Great Lakes, clusters of thunderstorms developed over the region during the late afternoon and early evening hours and moved eastward.  Many of these thunderstorms became severe, producing damaging wind gusts.  A few of the storms also produced hail, with one storm moving from eastern Albany County into southwestern Rennselaer County producing hail as large as two inches in diameter.  This particular storm produced a significant amount of wind damage across eastern Albany County, southwestern Rennsealer County and northern Columbia County as well.  About 1000 customers lost power from this one storm alone.
In addition to the wind and hail, the storms also produced heavy rainfall.  The rainfall fell heavy enough in a short period of time to cause flash flooding in the Amsterdam area, as well as across parts of western Rensselaer County.
With the passing of the cold front, the threat for thunderstorms ended by the late evening hours.

Thunderstorm Wind in COLUMBIA, NEW YORK
From 19-JUL-15 16:15:00 to 19-JUL-15 16:15:00 (EST-5)
Location: CHATHAM CENTER
Magnitude: 50.00 EG
Reported by: 911 Call Center

Power lines were reported down on Harris Road, off County Route 28, in the town of Chatham, as a result of thunderstorm winds.

Thunderstorm Wind in RENSSELAER, NEW YORK
From 19-JUL-15 15:53:00 to 19-JUL-15 15:53:00 (EST-5)
Location: SOUTH SCHODACK
Magnitude: 70.00 EG
Reported by: Amateur Radio

Extensive tree damage was reported near the intersection of Van Hoesen Road and South Schodack Road in South Schodack.  Many tree tops were snapped off and damage to cornfields occurred.

Thunderstorm Wind in COLUMBIA, NEW YORK
From 19-JUL-15 16:12:00 to 19-JUL-15 16:12:00 (EST-5)
Location: NIVERVILLE
Magnitude: 60.00 EG
Reported by: 911 Call Center

Power lines were reported down at State Route 203 & County Route 28 in Niverville (town of Kinderhook) as a result of thunderstorm winds.

Thunderstorm Wind in COLUMBIA, NEW YORK
From 19-JUL-15 16:11:00 to 19-JUL-15 16:11:00 (EST-5)
Location: NORTH CHATHAM
Magnitude: 70.00 EG
Reported by: 911 Call Center

Trees and power lines were reported down on Electric Park Road on the east side of Kinderhook Lake in Niverville as a result of thunderstorm winds.

Hail in ALBANY, NEW YORK
From 19-JUL-15 15:30:00 to 19-JUL-15 15:33:00 (EST-5)
Location: MALLORYS CORNERS
Magnitude: 0.88 
Reported by: Trained Spotter

Nickel size hail was reported during a thunderstorm in the town of Bethlehem.

Thunderstorm Wind in ALBANY, NEW YORK
From 19-JUL-15 16:23:00 to 19-JUL-15 16:23:00 (EST-5)
Location: BOGHT CORNERS
Magnitude: 50.00 EG
Reported by: NWS Employee

Large tree limbs were downed during a thunderstorm near Boght Corners.

Thunderstorm Wind in RENSSELAER, NEW YORK
From 19-JUL-15 15:47:00 to 19-JUL-15 15:47:00 (EST-5)
Location: CASTLETON ON HDSN AR
Magnitude: 50.00 EG
Reported by: Amateur Radio

A tree was down and on wires on Campbell Avenue in the village of Castleton-on-Hudson as a result of thunderstorm winds.

Thunderstorm Wind in ULSTER, NEW YORK
From 19-JUL-15 18:00:00 to 19-JUL-15 18:00:00 (EST-5)
Location: STONE RIDGE
Magnitude: 50.00 EG
Reported by: Amateur Radio

Numerous large branches were reported down in Stone Ridge as a result of thunderstorm winds.

Hail in SCHENECTADY, NEW YORK
From 19-JUL-15 16:30:00 to 19-JUL-15 16:30:00 (EST-5)
Location: AQUEDUCT
Magnitude: 1.00 
Reported by: NWS Employee

Quarter size hail was reported during a thunderstorm in Niskayuna.

Thunderstorm Wind in COLUMBIA, NEW YORK
From 19-JUL-15 16:15:00 to 19-JUL-15 16:15:00 (EST-5)
Location: OLD CHATHAM
Magnitude: 50.00 EG
Reported by: 911 Call Center

Trees were reported down on County Route 13 in the town of Chatham as a result of thunderstorm winds.

Thunderstorm Wind in SCHOHARIE, NEW YORK
From 19-JUL-15 16:20:00 to 19-JUL-15 16:20:00 (EST-5)
Location: COBLESKILL
Magnitude: 50.00 EG
Reported by: Law Enforcement

Multiple trees and branches were reported down in Cobleskill as a result of thunderstorm winds.

Thunderstorm Wind in SCHOHARIE, NEW YORK
From 19-JUL-15 16:30:00 to 19-JUL-15 16:30:00 (EST-5)
Location: SCHOHARIE
Magnitude: 50.00 EG
Reported by: Law Enforcement

Multiple trees and branches were reported down in Schoharie as a result of thunderstorm winds.

Thunderstorm Wind in COLUMBIA, NEW YORK
From 19-JUL-15 16:11:00 to 19-JUL-15 16:11:00 (EST-5)
Location: NIVERVILLE
Magnitude: 70.00 EG
Reported by: Amateur Radio

Many trees were downed at 123 Cortland Drive in Valatie (town of Kinderhook) due to thunderstorm winds.  Thunderstorm winds also downed trees on nearby Orchard Drive as well.

Hail in ALBANY, NEW YORK
From 19-JUL-15 15:38:00 to 19-JUL-15 15:40:00 (EST-5)
Location: SELKIRK
Magnitude: 2.00 
Reported by: Public

Hen egg size hail was reported during a thunderstorm in Selkirk.

Flash Flood in RENSSELAER, NEW YORK
From 19-JUL-15 15:59:00 to 19-JUL-15 17:00:00 (EST-5)
Location: CASTLETON ON HDSN AR
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

As a result of thunderstorm heavy rainfall, flash flooding occurred along Route 9J in Castleton.  A car was stuck in the roadway due to flood waters.

Thunderstorm Wind in SCHOHARIE, NEW YORK
From 19-JUL-15 16:30:00 to 19-JUL-15 16:30:00 (EST-5)
Location: MIDDLEBURG
Magnitude: 50.00 EG
Reported by: Law Enforcement

Multiple trees and branches were reported down in Middleburgh as a result of thunderstorm winds.

Thunderstorm Wind in RENSSELAER, NEW YORK
From 19-JUL-15 15:50:00 to 19-JUL-15 15:50:00 (EST-5)
Location: SCHODACK LNDG
Magnitude: 50.00 EG
Reported by: Amateur Radio

A tree was down on Knickerbocker Road in Schodack due to thunderstorm winds.

Hail in ALBANY, NEW YORK
From 19-JUL-15 16:32:00 to 19-JUL-15 16:32:00 (EST-5)
Location: LATHAM
Magnitude: 0.75 
Reported by: Amateur Radio

Penny size hail was reported during a thunderstorm at Exit 7 of the Adirondack Northway (Interstate 87) in Latham.

Hail in ALBANY, NEW YORK
From 19-JUL-15 15:36:00 to 19-JUL-15 15:38:00 (EST-5)
Location: CEDAR HILL
Magnitude: 1.75 
Reported by: Public

Golfball size hail was reported in the Cedar Hill hamlet of Bethlehem during a thunderstorm.

Thunderstorm Wind in ALBANY, NEW YORK
From 19-JUL-15 15:38:00 to 19-JUL-15 15:38:00 (EST-5)
Location: SELKIRK
Magnitude: 50.00 EG
Reported by: Newspaper

Trees and wires were reported down on Maple Avenue in Selkirk due to thunderstorm winds. One of the trees fell on a home.

Thunderstorm Wind in ALBANY, NEW YORK
From 19-JUL-15 15:40:00 to 19-JUL-15 15:40:00 (EST-5)
Location: SELKIRK
Magnitude: 50.00 EG
Reported by: Amateur Radio

Trees were downed along River Road in Coeymans due to thunderstorm winds.

Thunderstorm Wind in RENSSELAER, NEW YORK
From 19-JUL-15 15:46:00 to 19-JUL-15 15:46:00 (EST-5)
Location: CASTLETON ON HDSN AR
Magnitude: 50.00 EG
Reported by: Newspaper

A tree and numerous tree limbs were downed along Route 9J in Castleton-on-Hudson due to thunderstorm winds.  The downed tree and limbs partially blocked traffic along the roadway.

Thunderstorm Wind in RENSSELAER, NEW YORK
From 19-JUL-15 16:05:00 to 19-JUL-15 16:05:00 (EST-5)
Location: NASSAU
Magnitude: 50.00 EG
Reported by: Amateur Radio

A tree was downed in Nassau due to thunderstorm winds.

Thunderstorm Wind in SARATOGA, NEW YORK
From 19-JUL-15 17:18:00 to 19-JUL-15 17:18:00 (EST-5)
Location: GURN SPG
Magnitude: 50.00 EG
Reported by: Social Media

A large tree and wires were reported down on Northern Pines Road in the town of Wilton as a result of thunderstorm winds.

Thunderstorm Wind in MONTGOMERY, NEW YORK
From 19-JUL-15 16:36:00 to 19-JUL-15 16:36:00 (EST-5)
Location: CRANESVILLE
Magnitude: 50.00 EG
Reported by: Law Enforcement

A tree was reported down in Cranesville during a thunderstorm.

Thunderstorm Wind in MONTGOMERY, NEW YORK
From 19-JUL-15 16:25:00 to 19-JUL-15 16:25:00 (EST-5)
Location: CHARLESTON
Magnitude: 50.00 EG
Reported by: Law Enforcement

One tree was reported down in Charleston during a thunderstorm.

Hail in COLUMBIA, NEW YORK
From 19-JUL-15 16:07:00 to 19-JUL-15 16:07:00 (EST-5)
Location: NORTH CHATHAM
Magnitude: 0.88 
Reported by: Public

Nickel size hail was reported during a thunderstorm at 433 Rapp Road North in the town of Kinderhook.

Thunderstorm Wind in COLUMBIA, NEW YORK
From 19-JUL-15 16:10:00 to 19-JUL-15 16:11:00 (EST-5)
Location: NIVERVILLE
Magnitude: 78.00 EG
Reported by: NWS Storm Survey

A National Weather Service Storm Survey toured storm damage in Niverville.  Multiple trees and wires were downed around Kinderhook Lake in Niverville, especially on the Concourse, as a result of thunderstorm winds.  Some of the trees fell on homes or other outdoor structures.

Hail in ALBANY, NEW YORK
From 19-JUL-15 16:34:00 to 19-JUL-15 16:34:00 (EST-5)
Location: MAYWOOD
Magnitude: 1.00 
Reported by: Social Media

Quarter size hail was reported during a thunderstorm on Fairway Lane in Colonie via Facebook.

Thunderstorm Wind in SARATOGA, NEW YORK
From 19-JUL-15 17:06:00 to 19-JUL-15 17:06:00 (EST-5)
Location: GREENFIELD
Magnitude: 50.00 EG
Reported by: Law Enforcement

Trees and wires were reported down in Greenfield as a result of thunderstorm winds.

Thunderstorm Wind in COLUMBIA, NEW YORK
From 19-JUL-15 16:09:00 to 19-JUL-15 16:09:00 (EST-5)
Location: NORTH CHATHAM
Magnitude: 65.00 EG
Reported by: Law Enforcement

Trees and wires were downed at the intersection of Round Lake Road and County Route 28B in the hamlet of Niverville as a result of thunderstorm winds.

Thunderstorm Wind in COLUMBIA, NEW YORK
From 19-JUL-15 16:15:00 to 19-JUL-15 16:15:00 (EST-5)
Location: VALATIE
Magnitude: 55.00 EG
Reported by: Law Enforcement

Trees and wires were reported down on Kinderhook Street in the village of Valatie as a result of thunderstorm winds.

Flash Flood in MONTGOMERY, NEW YORK
From 19-JUL-15 17:00:00 to 19-JUL-15 18:00:00 (EST-5)
Location: HAGAMAN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Heavy rainfall from thunderstorms produced flash flooding on Route 30 between Amsterdam and Perth.  The roadway was partially closed due to flood waters.

Flash Flood in RENSSELAER, NEW YORK
From 19-JUL-15 17:20:00 to 19-JUL-15 18:45:00 (EST-5)
Location: TROY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Heavy rainfall from thunderstorms led to flash flooding in the city of Troy. A portion of Second Avenue (U.S. Route 4) was temporarily closed due to a foot and a half of flood waters across the roadway.

Thunderstorm Wind in RENSSELAER, NEW YORK
From 19-JUL-15 15:50:00 to 19-JUL-15 15:50:00 (EST-5)
Location: SCHODACK CENTER
Magnitude: 55.00 EG
Reported by: Trained Spotter

Trees were reported down in the town of Schodack as a result of thunderstorm winds.

Thunderstorm Wind in RENSSELAER, NEW YORK
From 19-JUL-15 17:40:00 to 19-JUL-15 17:40:00 (EST-5)
Location: HOOSICK FALLS
Magnitude: 50.00 EG
Reported by: Amateur Radio

A tree fell on a moving vehicle due to thunderstorm winds.  One person suffered a head injury as a result of the fallen tree.

Thunderstorm Wind in COLUMBIA, NEW YORK
From 19-JUL-15 16:12:00 to 19-JUL-15 16:12:00 (EST-5)
Location: VALATIE
Magnitude: 60.00 EG
Reported by: Newspaper

Trees were downed at 180 Maple Lane in the town of Kinderhook as a result of thunderstorm winds.

Thunderstorm Wind in COLUMBIA, NEW YORK
From 19-JUL-15 16:07:00 to 19-JUL-15 16:07:00 (EST-5)
Location: NORTH CHATHAM
Magnitude: 60.00 EG
Reported by: Public

Trees and utility poles were downed near a farm located at 433 Rapp Road North in the town of Kinderhook as a result of thunderstorm winds.

Funnel Cloud in COLUMBIA, NEW YORK
From 19-JUL-15 16:06:00 to 19-JUL-15 16:06:00 (EST-5)
Location: CHATHAM
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

A funnel cloud was spotted during a thunderstorm from the front of a supermarket to the north of Ghent.  The funnel cloud never reached the ground.

Thunderstorm Wind in ALBANY, NEW YORK
From 19-JUL-15 15:30:00 to 19-JUL-15 15:30:00 (EST-5)
Location: WEMPLE
Magnitude: 50.00 EG
Reported by: Trained Spotter

One tree was reported down in the town of Bethlehem due to thunderstorm winds.

Thunderstorm Wind in WASHINGTON, NEW YORK
From 19-JUL-15 18:00:00 to 19-JUL-15 18:00:00 (EST-5)
Location: HARTFORD
Magnitude: 50.00 EG
Reported by: Law Enforcement

Trees and wires were reported down in Hartford as a result of thunderstorm winds.

Thunderstorm Wind in ULSTER, NEW YORK
From 19-JUL-15 18:03:00 to 19-JUL-15 18:03:00 (EST-5)
Location: MARBLETOWN
Magnitude: 50.00 EG
Reported by: Law Enforcement

Numerous trees were reported down in Marbletown as a result of thunderstorm winds.

Thunderstorm Wind in COLUMBIA, NEW YORK
From 19-JUL-15 16:18:00 to 19-JUL-15 16:18:00 (EST-5)
Location: OLD CHATHAM
Magnitude: 50.00 EG
Reported by: 911 Call Center

Trees and power lines were reported down on Hamilton Lane in the town of Chatham as a result of thunderstorm winds.