Currently the storm is evolving beautifully! The circulation is beginning to deepen rather rapidly just off the coast of the Carolina's and you can see there is already an immense amount of moisture available and working into this system:
We have already seen light to even moderate bursts of snow across this state which started in the late morning and early afternoon hours. These bursts of light to moderate snow bands will continue through the remainder of the evening before snowfall rates substantially begin to pick up after 11:00 PM or so. Winds have also started to increase and will become an issue overnight as well.
This will be a very long duration storm with periods of light to moderate snows continuing throughout the afternoon tomorrow along with strong wind gusts.
What To Expect
Statewide, I am expecting an average of 18-24'' of snowfall..this is an average meaning some locations will end up with more than 24'' and some locations could perhaps end up with less than 18'' (but still more than 12''). Why is this? Well when you have these very intense systems you get what is called a deformation band...these bands are notorious for producing very heavy snowfall rates and dropping alot of snow in a very short amount of time. These bands can be a complicated mess when it comes to forecasting. The exact placement of them is something that isn't particularly modeled very well and also these bands can sometimes sit over a general area an pivot for hours...this is a situation in where areas can get upwards of 30"+ of snow. When taking to gauge where this banding may setup we typically look at the 850/700mb levels and look at their low pressure tracks along with vertical velocities. We will just highlight the 700mb level for time constraints:
The above image is taken from just one of the computer forecast models used for forecast guidance. However, the consensus is we will see a favorable enough low track to get the deformation band to pivot across CT, however, the question is does that occur across western and central CT or central and eastern CT? Something we won't 100% know until it gets going, however, at this time I'm leaning more towards the area highlighted in red on the snow map below as the highest likelihood of getting under the banding.
Another issue the deformation bands present is they also produce something called a subsidence zone...or what we weather weenies call "screw zones". As Newton once said, "what goes up, must come down" and that's pretty much what this is. Remember, the very strong lift describe above...that is air rising vigorously...well in response air must sink vigorously. So typically just to the north and west of this band will be an area of sinking air...this sinking air shuts off or lessens the rate of the precipitation falling...so while several locations are getting creamed, others are getting screwed. All this means that is there will be some areas that probably receive less than 18-20'' of snow and there is no way to tell where that will happen.
With this piece of info out of the way let's look at what to expect:
- Snowfall rates pick up as the evening and overnight progresses
- Snowfall rates will approach 2-3' per hour' at times and under the deformation band could approach 3-5'' per hour
- Thunder/lighting possible (also helping to enhance snow rates locally)
- Winds pick up...gusts along the coast approaching 60-70 mph. Further inland 45-55 mph
- Blizzard conditions expected tonight and tomorrow morning
- Numerous power outages likely due to strong winds and downed trees and utility poles
- Heaviest of the snow occurring between the hours of 11:00 PM and 9:00 AM tomorrow
Below is an updated map. Keep in mind the 24-36'' possibilities could be shifted depending on the deformation band...where it sets-up, where it pivots, and the duration the band sits over certain areas.
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