A weak F1 tornado touched down in Grandview On Hudson in Rockland County at approximately 3:30 pm EDT. After damaging a dock on the Rockland County shoreline, the tornado moved east to northeast, about 3 miles across the Hudson River. The tornado over turned a boat near the Tappen Zee Bridge then moved across the western shores of Westchester County over the town of Sleepy Hollow around 3:37 pm EDT. Houses and businesses along Beekman Avenue, Depeyster Street, and Chestnut Street in Sleepy Hollow experienced roof and siding damage associated with an F1 tornado intensity. The tornado continued on an east to northeast track to the Sleepy Hollow High School. A 58 mph wind gust was measured at 3:39 pm near the periphery of the tornado track.
As the tornado moved into the higher terrain of Pacantico Hills, the damage to trees and structures, which included the destruction of 2 small barns, indicated that the tornado intensified to an F2. As the tornado crossed Route 9A, significant structural damage occurred to the California Closet Building. In addition, a state trooper's vehicle was lifted briefly off the ground and a tractor trailer was blown over. As the tornado moved into Mount Pleasant and Hawthorne, extensive tree damage rated as a strong F1 was observed in the vicinity of Stevens Avenue. Minor structural damage and windows blown out were observed in the Summit Lake Industrial area. The tornado then moved into the Kensico Reservoir region across Routes 22 and 120 in the North Castle area. The path width was estimated at 200 to 300 yards based on the damage survey across Westchester County.