Good morning everybody, we’re in the calm before the storm for the daylight hours of our Wednesday. High to mid level clouds are beginning to stream into New England this morning, and that will continue as the day wears on, with a thickening and lowering of the cloud deck.
Personally, I love what I call “snow sky”: that silvery sheen in the could deck, muted sunshine that slowly fades away with time.
TODAY
It is cold out there this morning, with temps in the teens and dewpoint temps in the low single digits, as super cold and dry air has completely infiltrated the WMass region, which lays the atmospheric groundwork for our major snowfall tonight and tomorrow.
For today, we will see early partly sunny skies convert into filtered sunshine, muted sunshine, and then an overcast sky as the cloud deck thickens and works into the region.
Highs will only be in the low to mid 20s, which quite cold for the middle of December.
SETUP
Our mid-level low center will be driving through the Tennessee Valley, with a surface low well east over and off of the Georgian coastline. That low will track north-northeast off of the Delmarva coast and meet up with our mid level low, combine forces, and lift northeast off of the New Jersey coastline tonight, turning east-northeast south of Long Island, and remaining firmly to our south.
Combined with strong high pressure of Quebec draining super cold dry air southward, the two will clash as warm moist air from the low slams into that cold dry air, is forced to rise up and over it, and our snow shield will blossom across the WMass region tonight.
TIMING
Snow looks to begin a bit earlier, more like 7pm-10pm from southwest to northeast through our region (say Kent, CT through Fitchburg, MA).
Once it starts, it’s going to quickly become steady, and then moderate to heavy in intensity.
Surfaces will become snow-covered and slippery very quickly, given the super cold ground onto which the snow will be falling.
Snowfall rates of 1-2″ per hour are expected between midnight and 6am, with accumulating snow on either side of that time frame, and snow should last in varying intensities through Thursday morning, and taper off to snow showers and flurries by early to mid afternoon.
AMOUNTS
While part of me wants to leave last night’s 8-14″ south of the MA-VT/NH border and 6-10″ north of it alone, I am going to bump up totals even further by another 2″ based on overnight guidance and trends. It’s hard to see how most of us don’t get between .75″-1.25″ of liquid precipitation out of this event, and with a fluffy, powdery snow, snowfall ratios of 12-15″ of snow per 1″ of precip is quite reasonable to expect.
Therefore, I am going with 8-12″ either north of the MA-VT-NH line (or possible even north of the Rt. 9 corridor in southern VT/NH, which is Bennington to Brattleboro to Keene), and 10-16″ south of either of those lines mentioned above, with a few jackpot areas receiving up to 18″, 19″ or possibly 20″ of snow from this storm. Some northern portions of SVT/SWNH may receive under 8″ with a sharp northern cutoff, but that remains to be seen.
The jackpot areas, to me, still seem to be the east-facing slopes of the southeastern Berkshires, the southwestern hilltowns of WMass (western Hampden/Hampshire) and northwest CT in Litchfield County and western Hartford County, spreading westward into the central and southern Taconics of eastern NY.
WIND/VISIBILITY/OUTAGES/CHILL
As our low pressure makes its closest pass tonight and tomorrow, the combination of lower pressure and strong high pressure to the north, should produce northeast and east-northeast winds gusting 20-30mph at times tonight and early tomorrow, which will cause blowing and drifting of snow, reduced visibilities, brief whiteout conditions, and isolated outages from any winds that can gust up to 40mph, especially in high terrain areas. In addition, wind chill overnight should get down to around 0º in spots.
Folks, later tonight and tomorrow morning is NOT a time to be outside, at all, if you can absolutely help it. Better to stay in, and let the municipal road crews do their work, and silently thank them from inside as they rumble by your home.
No sense talking about weather after tomorrow afternoon at this point, though it’s going to be cold and with fair conditions until Sunday night, when some light snow or rain may move through the region. Oh, and Christmas Eve/Day could be stormy as well, but we’ll get to that after this storm is in the can.
I will update again by early afternoon, and again this early evening as our storm is setting in, and likely again later at night as it really starts to ramp up.
Check back in with me and this page like a TV channel that you turn to, even if I don’t show up in your feed, as I can’t control the powers that rule over me.
#Engage