Alerts:
CPV Weather
-Champlain Valley Weather has issued a Winter Weather Advisory for elevations of 1500 feet and higher in Orleans, Lamoille, Washington, Eastern Franklin, Eastern Chittenden, Eastern Addison, and Eastern Rutland Counties in Vermont, and Western Essex, Western Clinton, and Southern Franklin Counties in Northern New York for the potential of 2-6 inches of heavy wet snow.
-Champlain Valley Weather has issued a Flood Watch for all of Vermont, and most of Northern New York, excluding St. Lawrence County for 1-3 inches of rain. Where the Winter Weather Advisory is in effect, the flood watch is in effect for those same counties, but primarily below 1500 feet, where mainly rain will fall.
-Champlain Valley weather has issued a High Wind Watch for the Champlain Valley, and Rutland, and Bennington Counties in Vermont for the potential of strong to damaging winds. Sustained Northerly winds of 20-35MPH with localized gusts to 60MPH are possible, especially within the Champlain Valley, or on the South shore of Lake Champlain.
-Champlain Valley Weather has issued A Wind Advisory is in effect for all the remainder of Vermont, and all of Northern New York for strong winds. Sustained Northerly winds will be in the 15-30MPH range with gusts to 50MPH.
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NWS Burlington, VT
-The National Weather Service in Burlington, VT has issued a Flood Watch for portions of Northeastern New York, and For the all of Vermont excluding Grand Isle County, for the potential of 1-2 inches of rain, with localized amounts of up to 3 inches by Saturday.
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NWS Albany, NY
-The National Weather Service in Albany, NY has issued a Flood Watch for Bennington, and Windham Counties in Vermont for the potential of 1-2 inches of rain with localized amounts of up to 3 inches.
-The National Weather Service in Albany, NY has issued a Winter Storm Watch for elevations above 2000 feet, in Bennington, and Western Windham Counties in Vermont for the potential of 7 or more inches of snow by Saturday morning.
-The National Weather Service in Albany, NY has issued a Wind Advisory for Bennington, and Windham Counties in Vermont for the potential of strong wind gusts up to 50MPH.
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Champlain Valley Weather Discussion:
OVERVIEW
A strong, and dynamical storm is going to impact the region overnight tonight into early Saturday morning. A little bit of everything is expected with this storm, including heavy rain, strong winds, and heavy snow for elevations above 1500 feet.
Currently a 1006mb low pressure system is located east of the delmarva peninsula, and moving Northeast. As this system continues to move Northeast it will rapidly intensify. Already 3hr pressure falls indicate its deepening at 3mb's in a 3 hour period, so 1mb an hour. Thats pretty decent, however later tonight and tomorrow, even more rapid intensification is likely. All models are in agreement bringing this storm down into the 980-984mb range, which is a very strong system.
RAINFALL
Rain should continue to develop across the region overnight tonight, and become heavy at times after midnight. Rain will continue heavy at times across much of Vermont, for friday. There could also be some enhanced heavy rainfall for an extended period of time over the Champlain Valley, as significant Champlain Valley Convergence sets up, with a strong northerly flow. Rain totals across the entire area should range from 1-3 inches, some localized amounts near 4 inches is not completely out of the question at this time. The least amount of rain will be across the St. Lawrence Valley of New York, and the heaviest should be along the spine of the Green mountains. If the heavier amounts are witnessed then flooding will likely be an issue. Right now though only minor/ nuisance flooding is possible. The ground is still fairly saturated from the rains we had in late September.
WIND
The wind concern is a bit more difficult to forecast with high confidence as many factors are pushing towards strong winds, but a couple strong factors are against it. First off as this system rapidly intensifies the pressure gradient is going to tighten fast. Winds just above the surface will be howling at 40-60 knots, however cool rain, and cool temperatures at the surface may help prevent winds from mixing down to the surface. Now, with this in mind we have another factor to look at, which is the direction of the wind. The wind is expected to be coming from the north, and with the Champlain Valley, being a North-South oriented Valley, means that a South or North wind is funneled through the valley making winds stronger. So it may not take much mixing down of the wind to the surface for it to become gusty, especially in the Champlain Valley. Thats why I have issued a High Wind Watch for the Champlain Valley, and Rutland and Bennington Counties, as Winds could be into the 20-35MPH range with isolated gusts to 60MPH, especially the closer to the lakeshore you get. If this become more immenent then a High Wind Warning may be needed, if the winds appear to be lighter then a Wind Advisory will be issued instead. And just that, a Wind Advisory is what in effect for the rest of the region as winds should mix down enough everywhere for gusts to occasionaly reach 50MPH, especially across exposed terrain.
SNOWFALL
This is going to be the most difficult part of the storm to predict. There is so much against it, and so much for it happening. First off the time of year is not the greatest to get significant snowfall across the area, but yes it does happen, especially in the higher elevations. Models dont agree at all on this situation, some models are showing absolutly no snow, and other are showing 6-12, and some are showing up to 20 inches of snow (for the highest of elevations of course)!!! Now due to the fact of this rapidly intensifing low pressure system being off the coast, and a 500mb cutoff overhead or very close by, the dynamical cooling alone should be absolutly impressive, and even with some models showing snow down to 2500 feet, I feel that the pure dynamics of this storm are going to give us some suprises, and I will side closer with the NAM model as far as where areas of snow are likely. I dont agree on how much the NAM model is showing however, so I have cut back significantly on the snow amounts on that model. I feel that 2-6 inches is strongly possible for areas above 1500 feet, with the lower amounts being near 1500 feet, and the higher amounts being towards the highest summits, and this is why I issued a Winter Weather Advisory for certain counties. In all honesty, I would not be surpised if some places above 3500 feet (which there is not many of) see snow totals around 10 inches. I wouldnt be suprised to see some wet snowflakes mix in even below 1500 feet, in fact I personally dont feel its out of the question for areas in the Valley away from lake Champlain to see some wet snowflakes mix in with the rain late friday evening/ night into Saturday morning. The reasoning behind that, once again is the strong north wind causing significant convergence in the valley resulting in the potential of some very dynamically heavy rain, which could push some cooler air even closer to the surface than currently expected. One thing I will say, is that absolutly no accumulation will occur in the Valley if some snowflakes were to mix in. It would still be primarily rain, and this would only occur for a very brief period of time. Stay tuned for further updates on this developing situation.
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