Severe T-Storm/Tornado Event
An unusually strong upper level low pressure system responsible for a very chilly rainy day on the 15th, took up residence over the St. Lawrence river valley on Sunday, June 16. Very cold air in the upper levels of the atmosphere as well as a disturbance rotating around the base of the upper storm early in the afternoon triggered a round of violent thunderstorms. The degree of instability that the upper low created due to the coldness of the air aloft more than compensated for the lack of deep moisture and cool temperatures at the surface. High temperatures climbed to only 70 degrees with dewpoint temperatures in the 50's.
Steep lapse rates along the leading edge of the disturbance tracking over the region underneath the upper low triggered T'storms by 12:30pm that rapidly became severe as they marched east through the Capital Region, Berkshire county, and the mid Hudson valley and Litchfield county areas. Moderately strong mid level wind fields and low freezing levels in the atmosphere contributed to incidents of damaging wind and large hail with the stronger T'storms. Lightning was also particularly violent with the stronger cells.
Three tornadoes were spawned by the T'storms, one in Montgomery county, one in extreme southern Dutchess county, and the other in extreme southern Litchfield county, CT. The Dutchess and Litchfield county tornadoes were formed by the same parent supercell thunderstorm and had winds estimated on the F0 to F1 scale ranging from 70 to 115 mph. The eastern Montgomery county tornado in the township of Florida adjacent to Amsterdam, however, was the most unusual as it appeared to form from a non supercell (non rotating) thunderstorm. Tornadoes of this nature are called landspout tornadoes and are formed due to low level wind shears interacting with a thunderstorm updraft. Low level wind shear in the area of eastern Montgomery county was likely enhanced due to the convergence of the Mohawk and Hudson river valleys as well as thunderstorm outflow boundaries that had been produced by storms to the south and east of the cell responsible for creating the tornado. Typically, in the case of landspout tornadoes, the low level wind shear creates vertically spinning tubes of air, that when affected by a thunderstorm updraft can be stretched vertically thus causing them to briefly spin up creating a typically weak and short lived tornado. The Florida, NY tornado was in fact weak, being ranked an F0 with winds up to 70 mph and it was also short lived. The storm was also well documented. The following series of five photographs illustrates the tornado from 12:50pm to 1pm. The photographer is Eric Cichy Sr. from the township of Florida.
The following table is a listing of severe weather reports and storm damage as reported by Albany National Weather Service