Plowable Snow Event
The cold arctic air has been entrenched all day with temperatures barely reaching 20 in many locations after starting in the single numbers to lower teens this morning. Boston checked in with 11 degrees for a morning low and the record is 0 set in 1898. With all the cold air in place supplied by a strong high pressure system in eastern Canada north of New England, it seems that the stage is set for a significant snowfall and indeed it is going to be a plowable event. The least amount will be, as usual, over southeastern MA and Cape Cod with the outer Cape and Islands receiving under 2″. Expect 2-4″ over the rest of southeastern MA with amounts building up to 4-8″ in the Boston area southwestward into CT. The immediate coastal area may receive closer to 4″ with 8″ farther west of the city. More than 8″ is anticipated near and west of the portion of I-495 which is north of the MA Pike. Due to the very cold air holding on longer from north central MA northward, near or slightly greater than 1 foot of snow is projected thanks to the fluff factor. It appears that a classic coastal front is in the making as an easterly wind blows in from the ocean bumping up against the cold air damming in the western and northwestern suburbs. The converging air streams should create more lift and enhanced precipitation along and west of the front. With time, the coastal front will shift farther inland so rising surface temperatures are in the cards for just about everyone overnight. Additionally, it will be warming aloft and the latest guidance is hinting at a more rapid warm-up suggesting that a slight reduction in our snowfall projections MAY be warranted.
The secondary storm is forming over Delmarva right now and is slated to intensify rapidly on its journey toward Block Island to the Cape Cod Canal by 7-8 am. Sufficient warming is expected to produce the changeover line from south-southeast to north-northwest as the night unfolds. There should be a good slug of snowfall certainly near and north of most of the MA Pike before the transition to sleet, freezing rain and rain occurs. The heaviest precipitation will be over by 7-8 am in many areas and it will be tapering off after that and ending by 9-10 am. As the storm flies northeastward, some partial clearing is possible in the afternoon with a gusty wind. Temperatures will start out in the 30s early then fall back to near 30 late in the day and down to the teens tomorrow night as the sky becomes clear. Monday will feature a changeable sky of sunshine and passing clouds as an arctic cold front crosses the area. There might be a brief flurry with gusty breezes with highs in the middle 20s. The next impulse will be diving out of the Great Lakes and producing a period of at lest snow showers from midday Tuesday to the evening hours. There is a risk that if a storm develops quickly enoughnear the coast, there could be 2-3″ of snow before it exits into the Maritimes.
Looking ahead, the second half of next week will be quiet as a ridge of high pressure settles to the south of the region. As it does so, a southwesterly flow of air will warm it up to the upper 30s on Thursday and maybe to at least the middle 40s on Friday so there will be some melting og the snow. The next disturbances will be arriving from the Ohio Valley next weekend to create intervals of rain with highs in the middle 40s on Saturday and near 40 on Sunday.
Danielle Niles and I will be working the storm tomorrow morning and I shall also be here later in the day as well.
Enjoy the rest of the weekend.