Excessive Rain Event
Another in the December series of storms moved through the Northeast beginning early Saturday afternoon, December 16 and ending Sunday night, December 17. This was a major storm producing a long duration torrential rain event that began with a little ice on Saturday, and continued with dense fog and torrential rains by Saturday evening, dense fog and torrential thunderstorms on Sunday, and high wind by Sunday night. Widespread flooding began Sunday morning across the eastern Catskills and mid Hudson valley, and evolved throughout much of the remainder of eastern New York and western New England by Sunday afternoon. The combination of between two and four inches of rain, falling at a rate of an inch of rain per hour at times, and a frozen ground led to 100% runoff producing widespread flooding. Numerous road closures occurred throughout the area Sunday afternoon and night with scores of basements and several homes damaged from high water. Serious flooding occurred in Columbia county around Germantown, in Washington county in the town of Salem, in Berkshire county in Pittsfield, and in the Saratoga county towns of Mechanicville, Stillwater, and Waterford. 2.79" of rain fell at the Albany International Airport on the 17th and was a 24 hour rainfall record for the date. The combined rainfall from the 16th and the 17th totaled 2.95" at Albany. High wind from thunderstorms during the morning and early afternoon and the cold frontal passage Sunday night brought down wires and trees in some areas producing scattered power outages in New York and New England.
A cold night preceded the arrival of precipitation on Saturday, December 17. Cold air, however, was being overrun by much warmer air that was being forced north by a large storm centered over central Wisconsin at 10:00am. Rain began breaking out across the region during the early afternoon on the 17th and froze on contact in communities throughout the Mohawk valley, Capital Region, to southern Vermont and points north where temperatures only climbed to between 30 and 35 during the day. Icing, was relatively short lived with this system and only posed relatively minor travel problems into Saturday night. Dense fog, however, combined with torrential rains Saturday evening did produce poor driving conditions throughout the region.
By Saturday evening, several areas of low pressure centered from upper Michigan south to northern Kentucky were consolidating into one powerhouse storm. A warm front extended from the lows east to the mid Atlantic. By Sunday morning, the low centers had become one very strong storm that was located near Toronto, with the warm front moving north through New York and New England. The storm had created a deep conveyor belt of tropical moisture which streamed north up the Atlantic seaboard into the Northeast. Fifty to sixty degree air pushed into New York and New England and caused the atmosphere to destabilize which supported widespread thunderstorms during the morning and afternoon. Thunderstorms enhanced rainfall throughout the region and lead to the widespread flooding that occurred. High winds, associated with the storm, effecting higher elevations through the early morning, were mixed down to the ground in some of the thunderstorms, especially in Berkshire county, producing damage. A rare December severe thunderstorm watch went up for areas south and east of Albany through the afternoon to account for the isolated severe thunderstorms that developed. Temperatures soared to a high of 56 at Albany, and into the 60's in some of the hill towns.
Blinding rains and thunderstorms eased by early afternoon across much of eastern New York and by mid afternoon in western New England. Fog, however, persisted into the evening. A short period of sunshine developed during the mid afternoon with a spectacular, albeit rare, December rainbow that was spotted in many communities region wide. By 7:00pm Sunday evening, the very deep cyclone had lifted north into Canada and the cold front had passed east into eastern New England. Winds shifted into the west, northwest and increased to between 25 and 35 mph, with a few gusts to 50 mph as colder air moved into the area. Scattered flurries and snow showers also followed the front leaving snow accumulations of between a half inch and an inch and a half in some of the higher elevations of the Catskills, Adirondacks, and the peaks east of the Hudson river into western New England. Wells in Hamilton county reported 1.5", Summit in Schoharie county had a half inch, and Schenevus in Otsego county had about and inch of snow. Little of no snow accumulated in the Capital Region.
The table below is a listing rainfall totals from this storm from WeatherNet 6 and the National Weather Service cooperative and skywarn observers.