THE BLIZZARD OF 2015 IS 24 HOURS AWAY FROM BEGINNING. WINTER STORM WARNING FOR ALL OF WESTERN MASS, BLIZZARD WARNINGS FOR NORTHERN CT AND SOUTHERN WORCESTER COUNTY AND EMASS ARE NOW POSTED

Good evening everybody, we are enjoying the calm before what will become a long duration, very powerful Nor’easter that will evolve into a full-scale blizzard in southern New England, and likely one for the history books (or is it history blogs these days? I can’t keep up with you kooky kids).

I have finished making my food preparations, including making a huge batch of chili and rice, and I’d suggest you have plans as to how you’d deal with power outages, should they occur, including pre-cooking some food, having some non-perishable food items, water, candles/lighters, flashlights/batteries, TP, a full tank of gas in your car, sand/salt/shovel in your car if you must travel (which is HIGHLY ill-advised once we get to 9pm or so Monday evening), etc.

STORMS OF THIS MAGNITUDE ARE WHY IT’S IMPORTANT TO HAVE A PREPAREDNESS PLAN IN PLACE.

Having said that, there’s tons to talk about, and to be honest, every cell in my body is standing at attention with what I am seeing taking place. This confluence of atmospheric phenomena happens pretty rarely, and it’s not lost on me, that’s for sure, and as long as I have power, I will be here reporting for you and keeping you up to date with what’s transpiring across our region.

There are 5 major players on the map that are going to combine into an almost perfect development of low pressure just to our south, let’s deal with each one in turn:

PLAYER 1
A potent shortwave is digging aggressively into Kentucky and Tennessee at this hour. This upper low will push east-southeast towards the Carolinas, and emerge off the Carolina coast where it will interact with the warm waters of the Gulf Stream, which features SSTs (sea surface temps) of up to 70 degrees in places. This warm ocean water will provide ample fuel for explosive surface low development.

PLAYER 2
Another strong shortwave is already diving out of central Canada into Minnesota on the heels of the Kentucky low. Because the surface low that develops off the Carolina coast will be slowing down as it turns and pushes north-northeastward towards Nantucket, this Minnesota low will essentially smash into and merge with the developing coastal low, injecting it with additional energy to fuel development of the new Nor’easter.

PLAYER 3
The moderate snowstorm we had that wrapped up yesterday is now pushing towards Greenland, but it too developed very rapidly, and underwent bombogenesis. This caused the storm to slow down far to our northeast, and because of this, it is acting as an “upstream block”. You have to think of the jet streams and upper air currents as rivers. Air is in fact a fluid, and so acts like a fluid. Because this low is upstream of this developing low, it will cause our coastal low to slow down, leading to a long duration snowstorm.

PLAYER 4
The interaction between the upper lows that will have reached the Carolina/Virginia coasts, and the surface low that will be undergoing rapid cyclogenesis, will cause the surface low most likely (not set in stone, but appears likely) to be captured and drawn underneath the upper low. This “stacking” of low pressure from surface to high in the atmosphere ALSO causes storms to slow down, and even stall for a time. It would be powerful enough if ONE of these features were taking place, but it appears now that both will. As the storm tracks north-northeastward towards The Benchmark (40N/70W, about 75 miles due south of Nantucket), it will slow down, and possible even move retrograde towards the northwest or west. It could stall in place. It could do a loop. In other words, this low is not going to be in a hurry to get out of here, which will lead to snowfall accumulations being measured in terms of feet (1-3 feet) all across southern New England.

PLAYER 5
Cold, fresh, and strengthening high pressure to the north will move into an ideal position in Quebec above northern New England. The air to the north of this high is well below zero, so plenty of cold air will be available to fuel this system. As Tim Kelley of NECN says (one of my weather heroes), wind is air moving from high to low pressure. If you can picture a high over Quebec, and a low south of Nantucket, air wraps into almost a figure 8 pattern from north of the high’s center, clockwise down, around, and into the northwest side of the low’s center, then counterclockwise down to its south, and wrapping up into its center. This very cold air gets wrapped into the low, and entrenches to the north of the low. The cold air fuels the low’s development, and this dense cold air provides a widespread dome of cold air for precipitation to overrun, resulting in widespread heavy snow as the low develops, and tracks north.

As our stacked low, and Canadian high each strengthen, winds will increase out of the northeast (hence the term “Nor’easter”), and very heavy snow on the order of 1 to as much as 4 inches per hour (!!) will develop over Western Mass after midnight and especially into Tuesday, all day long. Winds will gust to up to 40 to 50mph at times, resulting in blizzard conditions in Western Mass (most likely in eastern Hampshire and eastern Hampden counties). Thundersnow is very possible on Tuesday as strong convection occurs, and banding features set up, as heavy snow is thrown across our area from the ocean. A dry slot could move into eastern Mass for a time as the storm wraps up, but I think we stay on the west side of that feature, which is also called the deformation zone. Heavy snow banding can take place in this area, but it’s not possible to know where the heaviest banding takes place.

Roads will quickly become hazardous by late Monday night. Blowing and drifting of snow will occur, as this will be all snow for everywhere in New England except extreme southeast MA, Cape and islands where rain could mix in at times. The quality of the snow will be fairly dry, and given that we will see 1.5 to 2.5 inches of liquid water being squeezed out of the sky in the form of snow, I believe Western Mass will see a widespread 18-30 inches of snow from this blizzard.

Power outages are possible, due to high winds, although less so because of snow as it won’t be of the heavy wet variety.

HURRICANE FORCE WIND WARNING IN EFFECT FOR THE EASTERN MASS COAST
Folks down in southeast MA need to be very concerned, as hurricane force winds will blow hard out of the northeast, upwards of 70 to 80mph!!! Combined with heavy wet snow, and there will be a stripe of communities down that way that could have widespread, and potentially longer duration power outages.

Strong coastal flooding is possible, as seas will be building up to 25 feet in height. The storm will wind down early Wednesday morning, and another moderate snowstorm is possible for Friday, too.

I think you get the picture. I will update you all in the morning, and as necessary, and like I said, as long as the power is on, I will be blogging throughout the storm, and look forward to receiving your condition reports, and interacting with you as much as I can.

Have a great rest of the night, and batten down the hatches.