|Storm total snowfall from the January 22-24 storm.|
There is no reason anyone in the storm's path should not have been prepared for what occurred. The potential for significant winter weather along the storm's projected path started coming into focus a week out. By Wednesday it was pretty clear that the mid-Atlantic region was the bullseye. The various atmospheric models were being remarkably consistent, increasing confidence in the forecast of heavy snow over a large area from the Appalachians to the coast. One of the major uncertainties in the forecast was how far north the snow would develop. Most of the models kept significant snow accumulations south of New York City, though by late in the week one model was indicating heavy snow in New York City. It was the outlier at the time, and while forecasters were aware of the possibility of this occurring other data seemed to contradict this solution. That being said, one message forecasters did consistently convey was that the northern edge of the heavy snow would be sharply defined, and that a shift of just a few miles could significantly change the forecast for locations along the northern edge of the snow shield.
As it turned out that one model ended up being mostly correct, and the other models eventually caught on. The result was two feet of snow in New York City. What about the sharp northern edge? It was. Fishkill, NY in Dutchess County received no measurable snow from this storm, while about 12 miles to the east southeast is the town of Lake Carmel in Putnam County, NY received 12" of snow.
This storm was fairly intense and slow-moving. The pressure gradient (the change in pressure over a given distance) was rather steep, producing strong winds. The onshore easterly winds circulating around the low on the north side of the storm track generated a storm surge at high tides which in some areas exceeded the surge experienced during Hurricane Sandy. The winds persisted through three high tide cycles and helped produce major coastal flooding. The tidal flooding exceeded that of Hurricane Sandy from Stone Harbor, NJ south to Cape May, and also at Lewes, DE located at the entrance to Delaware Bay.
|Wind gusts recorded during the January 22-24, 2016 storm.|
Credit: NWS Mt. Holly
Winds were a major feature of this storm and were the reason for the Blizzard Warnings that were issued for the area from Washington, DC to New York City. The highest wind gust recorded was 68 mph at the mouth of Chesapeake Bay, with gusts from 60 to 65 recorded along the coasts. Was the blizzard warning justified? This map shows the number of hours that various locations experienced visibility 1/4 mile or less and winds gusts equal to or greater than 35 mph.
The consecutive hours of heavy snow where driven by the the very strong upward vertical motion within this storm system and a basically unlimited supply of moisture from a warmer-than-normal Atlantic Ocean. Thundersnow was observed in a number of locations from Washington DC northward during the storm, indicative of strong convection.
|This photo was taken by astronaut Scott Kelly from the International Space Station on January 23. The bright spot in the middle of the photo is a lightning flash over eastern Virginia during the snow storm.|
The mid-Atlantic and the northeast had everyone's attention over the weekend, but as the storm approached Thursday and Friday winter weather spread from the lower Ohio Valley into the southeast. Sleet and snow occurred as far south as Georgia, Alabama, and the Carolinas. Parts of North Carolina received several inches of sleet while western mountains got a foot of snow or more.
How did this storm measure up to past nor'easters? According to the Regional Snowfall Index produced by the National Centers for Environmental Information (NCEI), this storm ranks 6th on the list of major snowstorms with an RSI of 17.758. The area covered by 30 inches of snow or more was 1220 square miles, with an affected population of 1,121,182. The population affected by 4 or more inches of snow was 47,293,970. The highest ranking storm for the Northeast Region was the storm of February 21-27, 1969 with and RSI of 34.026.
There were many daily snowfall records set during the storm, too many to list here. Central Park totaled 26.8in inches of snow, falling a tenth short of the record28.9 inches in February 1-2, 2006. 24-hour snowfall records ere set at Kennedy Airport (30.3"), LaGuardia Airport (27.9"), Islip (23.4"), and Newark, NJ (27.5"). The official (so far) total for Washington DC is 17.8 inches (at Reagan National Airport), but there is some question about that amount due to measurement procedures. You can read more about this in this article by the Capital Weather Gang. The CoCoRaHS station at the White House (DC-DC-19), measured a total of 21.9 inches of snow during the storm.
|The observations from CoCoRaHS station DC-DC-19, the White House.|
CoCoRaHS observers did a great job during this storm. The heavy snowfall rates and high winds made for very challenging measurement conditions. 33 CoCoRaHS observers reported 30 or more inches of snow for the two-day storm from Maryland,Virginia, West Virginia, Pennsylvania, New York, and New Jersey.
Once the nor'easter ended the snow cover across the U.S. was at 53 percent with an average depth of 5.6 inches. The relatively mild and quiet weather since the storm has rapidly decreased the snow cover in the Midwest, south, and reduced the depth substantially in the east. Today snow cover was down to 38.5 percent with an average depth of 4.6 inches. Last year on this date it was 27.5 percent.
|Snow cover on the morning of January 25, 2016.|
|Snow covr on the morning of January 28, 2016|