Major East Coast Storm To Bring Blizzard Conditions

Alert Details:
         The National Weather Service in Burlington has issued a Winter Storm Warning for much of Vermont, excluding the Champlain Valley, the Warning also covers Northern New York, excluding the Champlain and St. Lawrence Valley's. The Winter storm warning is in effect for the potential of 6-12 inches of snow, with wind gusts up to 50MPH. The Winter storm warning for the previous storm still remains in effect for all the same areas as earlier.

       & Champlain Valley Weather has issued a Blizzard Warning for much of Vermont, and Northern New York, for 6-12 inches of snow, with sustained winds of 20-30MPH with gusts in the 50-55MPH range. A Blizzard Watch remains in effect for the Champlain Valley, and the extreme southern Connecticut River Valley in Vermont, for the potential of 3-6 inches of more of Snow accumulation combined with strong winds in the 15-25MPH with gusts in the 45-50MPH range.


Champlain Valley Weather Discussion:
         As we get done one storm, we start another. This storm has been extremely hard to forecast, and the potential of busting on this is moderate. There are so many aspects to this storm to figure in to consideration, its tough. Infact there has been no winter storm like this, as far as track and strength go, in the past 30 years to compare it too. The National Weather Service did a search on the CIPS analog system, and there were no matches for the past 30 years. While yes, I am sure there has been a storm similar to this since records began, there is no detailed data to help with the forecast. Therefor, we are going into somewhat uncharted territory.

         Now while there is no winter storm comparison for this type of track and strength of a storm in recent years, we can still look back to a few things for help. The storm position will result in a easterly wind across the area. As we know, with an easterly flow, the mountains block (shadow) precipitation from the Valley's, so areas such as the Champlain Valley, and the Connecticut River Valley, tend to be warmer, and drier, but the eastern slopes of the green mountains tend to be cooler and wetter, due to upslope dynamics. We also know easterly winds tend to funnel through the mountain gaps and produce very strong to damaging winds, along east facing slopes, but of most significance the western slopes of the green mountains.

         Now with the above known, temperature problems still exist, with a storm track such as this, warm air will wrap up and around the east side and over towards the north. This will likely bring in warm Atlantic moisture, which could result in warm valley temperatures and not much snow, especially if significant downsloping occurs, which is very possible. But to complicate the matter more, winds may have just enough of a Northerly component across the Champlain Valley, that temps could remain cooler, and the downsloping would not be as pronounced.

         So at this time, this is what I am thinking, rain/snow mix will develop tonight and become potentially heavy tomorrow late afternoon or early evening. By Friday afternoon, total snow accumulations look at this current moment, 6-12 inches for the higher elevations, and 3-6 inches in the valley locations. For the Champlain Valley its tough, at this point I am calling for 3-6 inches, but if a northerly wind component can establish itself, and have good effect then we may end up with more snow. If there is not much of a northerly wind component, then we may see much less then 3-6 inches. With that said, the Valley locations remain under a Watch, while the Higher elevations are under a Warning. With these being Blizzard alerts, that means yes, winds will be a factor. Winds of 20-30MPH with gusts in the 50-55MPH range can be expected across the higher elevations, and western slopes especially. The Valley locations will see sustained winds of 15-25MPH with gusts in the 45-50MPH range. This will cause significant blowing and drifting of snow, especially across the higher elevations. As things become more certain, then a Blizzard Warning or Winter Weather Advisory will be issued for the Champlain Valley, and Southern Connecticut River Valley. Stay tuned for further updates on this developing weather situation.