Heavy Long Duration Snow Storm
This was a long duration snow storm that began during the evening and early nighttime hours on Monday, February 28 and continued into the early morning on Wednesday, March 2, encompassing approximately thirty hours. The snowfall the system produced in most cases equaled, and in some communities exceeded, the season's heaviest snowfall to date which occurred in the January 22-23, 2005 Nor'easter. 11.5" of snow fell at Albany in the January storm, which compared closely to the 11.9" of snow that fell at Albany with this one. (The 10.7" of snow that fell on March 1 at Albany set a 24 hour snowfall record for the date.) This storm also produced one of the most uniform snowfall distributions of any storm that has hit the area in recent times, which is quite unusual due to the complexity of the local terrain. The terrain is typically responsible for the normally huge variances in snow accumulations that typically occur over eastern New York and western New England with large snow storms. But in this case, a general 10"-15" of snow fell over the entire area, excluding additional localized snowfall that resulted from lake effect that occurred through the day on the 2nd.
As is typical with large Northeast snow storms, the scenario that came together to produce the widespread snowfall that occurred from the Midwest through the mid Atlantic and Northeast states was complex. The storm was made up of two distinct systems that eventually merged over the Northeast into one very large upper level storm. But initially, a storm plowing through the Midwest produced widespread snows over that region. Simultaneously, a strong storm in the southern branch of the jet stream produced copious amounts of rain and severe weather over the gulf coast and Florida. The southern storm tracked to the mid Atlantic coast where in classic fashion encountered a strong temperature contrast zone just off shore of the outer banks of North Carolina, allowing it to rapidly develop. As the storm developed and tracked to the northeast to a position off of Cape Cod by early Tuesday morning, March 1, the storm over the Midwest moved into New York. The combination of the coastal low passing south of New England and the Midwest storm produced a significant round of snow over eastern New York and western New England.
Early in the storm, however, very dry air in the low levels of the atmosphere, illustrated by very low dewpoints in the single digits, during Monday evening, February 28, and a strong easterly downslope flow over the Berkshires and Greene mountains in the lowest 5000' of the atmosphere, caused much of the initial snow to dissipate before it reached the ground. Snow did develop between 6 and 7pm in Ulster, Dutchess, and Litchfield counties, but took until between 10pm and 11pm to make it into the Capital Region, and until between 11pm, and 1am before it made it into the Mohawk Valley, Adirondacks, and Vermont. Once the snow began, however, it picked up in intensity very quickly falling at rates that occasionally exceeded and inch per hour, through about 8am on March 1st. Between five and nine inches of snow, representing the main brunt of the storm, had accumulated by approximately 9am on the 1st over most of the area.
As the main coastal storm pulled away, the snowfall became much lighter and more intermittent through the majority of the afternoon on the 1st, accumulating up to 3" more in spots, bringing storm totals to between 7"-10" on average throughout most of the area by 7pm. Due to the higher early March sun angle, even though the day was overcast, plowed paved surfaces quickly melted down, leaving generally wet roads throughout the region during the day. However, as the weaker Midwest storm meandered into New York during the late afternoon and the nighttime and hours on the 1st, along with an upper level disturbance, and local terrain effects, namely a Mohawk/Hudson wind convergence zone, snowfall again intensified in the Mohawk valley, Catskills, and greater Capital Region, falling at times at rates of an inch per hour through midnight. With the loss of daylight, roads quickly became snow covered again with very slippery travel conditions through the night. Snowfall continued through the pre-dawn hours on the 2nd, but was generally much lighter and more intermittent. By 8am Wednesday, a general 10"-13" of snow had accumulated over the region with a few hot spots coming in between 13"-15" of snow.
Through the day Wednesday, the 2nd, strong winds behind the departing system blowing over Lake Ontario created some strong lake effect snow bands in the Mohawk valley and the Catskills. The northwest wind was an upslope wind in the hills east of the Hudson river and in Western New England which produced patches of persistent light snow in the higher terrain. Through Wednesday the 2nd, localized additional snow accumulations in the Mohawk valley and Catskills ranged from 1"-3". The Mountains in southern Vermont, namely Woodford, Mt. where we have a WeatherNet 6 weather spotter, reported 23" of snow at the 2400' elevation due to the combined effects of the storm and persistent upslope snows.
The strong winds on the 2nd produced significant blowing and drifting snow that created occasional whiteouts and thus poor travel conditions especially on exposed rural roads. Travel conditions in the wake of the storm on the 2nd, due to the blowing snow, ended up being worse in some areas than during the period when the brunt of the snow was falling early Tuesday morning March 1.
The map below shows the snowfall distribution from the February 28 to March 2, 2005 storm from 7pm on the 28th through 8am on the 2nd. The distribution was created using snowfall totals observed and reported by WeatherNet 6 weather spotters. Individual snowfall totals for the event are listed in the table below the map. (This distribution map does not include localized additional snow accumulations that occurred through the day on the 2nd that resulted from lake and mountain effect snow bands.)
The table lists the WeatherNet 6 storm total snowfall reports from the February 28 to March 2, 2005 storm