An anomalously warm and humid air mass was over eastern New York April 27th and 28th. Temperatures were 15 to 25 degrees above normal. A warm front lifted north of the region on Wednesday, April 27th with an area of heavy showers and embedded thunderstorms. This front became stationary near the Saint Lawrence River Valley and northern New England.  A disturbance in the upper levels of the atmosphere and an area of low pressure moving towards the Great Lakes Region focused another round of showers and thunderstorms that impacted the western and central Mohawk Valley, Adirondack region, and the Upper Hudson River Valley including the Lake George Region late Wednesday afternoon into the early evening, April 27th.
Another wave of low pressure moved into the eastern Great Lakes Region Thursday morning, April 28th.  This low intensified as it approached and had strong upper level support favorable for strong to severe thunderstorms.  A supercell thunderstorm produced a tornado that  touched down in southern Herkimer County producing damage in Frankfort early in the morning. Severe thunderstorms produced damaging winds north and west of the Capital Region during the morning hours. Very heavy rainfall was associated with the storms.
Lightning strikes started fires in a couple locations. The Mayfield Presbyterian Church in Fulton County was destroyed and the Stuyvesant Reformed Church in Columbia County suffered minimal damage.

On June 10th, The U.S. Department of Homeland Security's Federal Emergency Management Agency (FEMA) announced that federal disaster assistance had been made available to the state of New York to supplement state and local recovery efforts in the area struck by storms, flooding, tornadoes, and straight-line winds during the period of April 26 to May 8, 2011. This includes the counties of Hamilton, Herkimer, and Warren in east central New York.

Thunderstorm Wind in ULSTER, NEW YORK
From 28-APR-11 10:08:00 to 28-APR-11 10:08:00 (EST-5)
Location: HONK HILL
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Trees were reported down on wires in Napanoch due to strong thunderstorm winds.

Thunderstorm Wind in FULTON, NEW YORK
From 28-APR-11 05:29:00 to 28-APR-11 05:29:00 (EST-5)
Location: PROGRESS
Magnitude: 50.00 EG
Crop damage: 0.00K
Reported by: Fire Department/Rescue

A tree was reported down on a house on Blanchard Road due to strong thunderstorm winds just outside of the City of Gloversville.

Flash Flood in HERKIMER, NEW YORK
From 28-APR-11 06:00:00 to 28-APR-11 12:00:00 (EST-5)
Location: GRAVESVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

The West Canada Creek and its tributaries were out of their banks and causing widespread flooding of roadways with the shoulders of many roads washed away.  Widespread basement flooding also occurred.
The following roads were reported closed due to flooding:
Route 8 between Route 28 in Poland and Route 10 in Piseco, washed away in several locations.
Route 8/28 bridge across the West Canada Creek at the Herkimer-Onieda county border.
Route 28 between the villages of Middleville and Newport.
Route 168 east of Route 28 in the Town of Mohawk.

Thunderstorm Wind in SCHOHARIE, NEW YORK
From 28-APR-11 06:30:00 to 28-APR-11 06:30:00 (EST-5)
Location: MIDDLEBURG
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Multiple trees and wires were reported down due to strong thunderstorm winds in Milddleburgh.

Flash Flood in HERKIMER, NEW YORK
From 28-APR-11 05:25:00 to 28-APR-11 05:25:00 (EST-5)
Location: NEWPORT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A car rescue occurred on Strumlock Road near Honey Hill Road in Newport due to high water from heavy rainfall.

Thunderstorm Wind in SARATOGA, NEW YORK
From 28-APR-11 06:50:00 to 28-APR-11 06:50:00 (EST-5)
Location: GANSEVOORT
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Route 32, Schuylerville Road, between Route 50 and Jewell Road was reported closed because of downed wires due to strong thunderstorm winds just to the east of the Village of Ganesvoort.

Thunderstorm Wind in WARREN, NEW YORK
From 28-APR-11 06:00:00 to 28-APR-11 06:00:00 (EST-5)
Location: BOLTON
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Trees and wires were reported down due to strong thunderstorm winds on Route 9N in Bolton.

Tornado in HERKIMER, NEW YORK
From 28-APR-11 04:04:00 to 28-APR-11 04:07:00 (EST-5)
Location: FRANKFORT UTICA ARPT
Tornado F-scale: EF1
Crop damage: 0.00K
Reported by: NWS Storm Survey

A National Weather Service survey team confirmed a tornado in Frankfort, an EF1 with estimated maximum wind speed of 100 mph.  Numerous trees were snapped and uprooted. Structural damage to homes included roofs and siding being torn off. A garage was moved off its foundation. Significant damage occurred to a house on Brockway Road.

Thunderstorm Wind in HERKIMER, NEW YORK
From 28-APR-11 04:40:00 to 28-APR-11 04:40:00 (EST-5)
Location: BURRELL CORNERS
Magnitude: 50.00 EG
Crop damage: 0.00K
Reported by: Trained Spotter

Three pine trees were reported sheared and/or uprooted due to strong thunderstorm winds on Route 170A just south of Route 29 in Salisbury Center. In addition, three sheds were reported blown apart and one rolled along with bricks missing from the chimney of a house.

Thunderstorm Wind in HAMILTON, NEW YORK
From 28-APR-11 05:10:00 to 28-APR-11 05:10:00 (EST-5)
Location: SPECULATOR
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Trees were reported down due to strong thunderstorm winds along Route 30 outside the Village of Speculator.

Thunderstorm Wind in SCHENECTADY, NEW YORK
From 28-APR-11 06:25:00 to 28-APR-11 06:25:00 (EST-5)
Location: SCHENECTADY
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Numerous tree limbs reported down due to strong thunderstorm winds in Central Park in Schenectady.

Thunderstorm Wind in GREENE, NEW YORK
From 28-APR-11 09:51:00 to 28-APR-11 09:51:00 (EST-5)
Location: ASHLAND
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

A tree limb was reported down on wires and burning on Sutton Hollow Road in Ashland due to strong thunderstorm winds.