Flash Flood in New York, January 19 to 20, 1996

The most disastrous flood event in more than twenty years struck central New York from the early morning of the 19th to the evening of the 21st. Significant widespread flooding of streams, rivers, homes and businesses, streets and highways, woodlands, and farmland occurred as a result of rapid snowmelt and nearly simultaneous storm runoff. Every county in central New York experienced road closures due to washouts, mudslides, and failed, damaged, or weakened bridges. There were six known fatalities. In Delaware County, five occupants of one car were killed when their vehicle and three others were swept into the Cannonsville Reservoir. A roadway over a sluice from an upstream pond collapsed before a New York City Bureau of Water Supply patrolman could warn the driver. Two occupants of one vehicle and the patrolman were rescued. The driver of the fourth vehicle was found dead several months later. A major fire, destroying two downtown stores, occurred during the flooding in Walton (Delaware County). Nearly every county declared a county-wide State of Emergency with remaining counties having locally declared States of Emergency on January 19th. Most States of Emergency were lifted by late on January 20th. Many counties experienced small-scale evacuations of homes and/or businesses. A strong low pressure system tracked northward across the Great Lakes on the morning of the 19th, bringing mild air into the region on strong southerly winds gusting to 45 MPH. The strong winds played a significant role in eroding the snowpack - snow depths by sunrise on the 19th ranged from only a few inches to bare ground, down from depths of one to two and a half feet the day before! Water equivalents of the eroded snowpack ranged from two and a half to five inches. During the early morning hours of the 19th, a line of heavy rain showers and embedded thunderstorms developed ahead of a strong cold front. Streams and creeks were approaching bankfull due to runoff from the snowmelt. Rainfall intensified over the region as the front slowed its eastward progress. Rainfall amounts ahead of the front were generally between one and a half and two and a half inches, with many locations receiving rainfall rates of one-half to one inch in an hour. Serious flooding of streams and creeks began across the Finger Lakes Region and Central Southern Tier Counties during the mid to late morning, and commenced across the remainder of central New York during the afternoon as the heavy rain moved east. The cold front moved across the region during the afternoon, causing temperatures to drop from the 50s into the 20s, and the rain to change to snow (with some areas receiving a period of sleet and/or freezing rain) in only one to two hours. The rapid drop in temperature that caused standing water to freeze rapidly, in concert with the one to two inches of snow that accumulated in most areas by evening, created very slippery conditions throughout central New York. Flash floods that began early on the 19th gave rise to main stem river floods that persisted until the evening of the 21st. Near record river flooding occurred on January 19th and 20th over the Chemung, upper Susquehanna, and upper Delaware River basins. At Waverly, in Tioga County, the Susquehanna River crested at its third highest level of all time, at 20.35 feet, which was about one foot lower than the all time crest of 21.40 feet recorded on March 19, 1946. Most forecast points had fallen below flood stage by the evening of January 21.