Friday-Saturday, December 11-12, 1992 Super Nor'easter

A major east coast storm had been forecast for almost a week. The storm developed in classic form along the mid Atlantic coast, intensified rapidly, and began its expected trek up the eastern seaboard. Forecasts called for up to two feet of snow in upstate New York and Western New England, with high winds along the coast. The storm developed into everything it was predicted to be, almost. Hurricane force winds lashed New York and Boston.  In fact winds gusted to 90 mph along the New Jersey coast on the 11th, with gusts ranging from 70-80  mph in New York City and Boston Friday night into the day Saturday.  Almost three inches of rain fell in Philadelphia, New York City, and Boston causing considerable poor drainage and urban street flooding.  The combination of the slow motion of the storm with the persistent and intense easterly winds caused successive storm tides, much higher than normal, creating a much more serious flood in New York City by the mid afternoon of the 11th.  In fact the flooding was so severe that many describe the scene as one of complete pandemonium with the subways shutdown and major roads inundated halting almost all city wide transportation.  While the coast was being pummeled,  heavy snow was falling over interior areas of upstate New York and New England where temperatures were lower.  However, the heavy snow was selective in where it fell, never really materializing over the Capital Region, but falling at rates of 2"-4" an hour over the Berkshires, Catskills, and the Worcester hills in central Massachusetts for many hours.

As it turned out, the main mechanism for producing precipitation with this storm was its strong easterly low level circulation of moisture laden air. There was very little else with the storm to cause the air to rise and thus produce precipitation. The east winds, as they interacted with the higher terrain in Worcester County, MA were forced to rise quite sharply, a process called upslope flow. A storm total of 40" of paralyzing snow occurred at Worcester, MA as a result.  On the leeward side of the Worcester hills the air descended, and thus compressed causing it to warm and dry out.  The subsequent downslope flow into the Connecticut river valley, dried the air out so much that average snowfalls amounted to only three inches around Hartford, CT, and Springfield, MA. Upslope winds then on the east side of the Taconic range in Berkshire county, MA, caused two to four feet of snow to pile up, while drying downslope winds over the Hudson valley limited snowfall to between four and six inches.  Upslope flow along the eastern slopes of the Catskills then caused one to two feet of snow to fall with blizzard conditions.

In most storms there are other elements, such as very strong jet stream components and upper air low pressure centers, that produce upward motion in the atmosphere and often compensate for the downslope or valley shadow effect causing a more even snowfall distribution.  This storm, however, was unique in its configuration as the other players just were not there.  The result was this very pure example of how differences in local terrain can profoundly effect the weather over a local area in the absence of other mechanisms to create precipitation.

Conditions in the Capital Region through the entire day on Friday, December 11 were rather tranquil while at the same time blizzard conditions were occurring in the surrounding hill towns, and hurricane force winds with damaging storm tides were battering and inundating coastal areas.  The easterly flow, downsloping into the Hudson valley off of the higher terrain in western New England caused a light mixture of sleet and rain to fall, with temperatures ranging from 35° to 40° during the day.  However, a rise in elevation by as little as 500' made the difference between light sleet and rain, and heavy snowfall.  No appreciable snow accumulated in the Capital Region on the 11th.

During the night of the 11th and the early morning of the 12th, the storm elongated and reformed south of Cape Cod, MA, producing wind gusts close to 80 mph over the Cape and the Islands as well as Boston. Winds over eastern New York shifted from easterly to north, northeasterly, easing the downslope effect which allowed the air to cool, finally supporting snow in the Hudson valley.  Most of the accumulating snow in the Hudson valley, which ranged from 4"-7", occurred late Friday night into the morning on Saturday.

The storm ended late Saturday over the entire Northeast leaving many communities buried under exceptionally heavy amounts of snow, while others were left with only a little.

The storm is considered a rare super Nor'easter due to its intense compact nature and very slow motion along the coast.  At times, the system developed an eye like structure and had profound damaging effects along the coast due to an long period wave battery, causing coastal erosion and severe coastal flooding.   Power was knocked out to thousands throughout the Northeast due to the combined effects of a heavy wet snow and the high winds.  Few Nor'easters have packed the punch that this one did, even though it only produced about 6" of snow at Albany.

The table lists a few of the reported snowfall accumulations with the December 11-12, 1992 Super Nor'easter as reported by the Albany National Weather Service 

Town County Snowfall Report
Savoy, MA Berkshire 48.0"
Peru, MA Berkshire 48.0"
Sandisfield, MA Berkshire 40.0"
Becket, MA Berkshire 36"
Adams, MA Berkshire 36"
Pittsfield, MA Berkshire 30"
Stamford Delaware 37"
West Kill Greene 36"
East Jewett Greene 36"
Gilboa Schoharie 36"
Windham Greene 30"
Canajoharie Montgomery 20"
Delanson Schenectady 19"
Gloversville Fulton 10"-12"
Amsterdam Montgomery 10"-12"
Berlin Rensselaer 12.5"
Albany Airport Albany 6.2"
Clifton Park Saratoga 6.2"
Niskayuna Schenectady 5.0"
Round Lake Saratoga 2.5"
Rhinebeck Dutchess 9.0"
Poughkeepsie Dutchess 7.0"
Lake Luzerne Warren 6.0"
Warren County Airport Warren Trace