7:30AM
DAYS 1-5 (JANUARY 5-9)
On we go with the Pacific flow. However some modifications or adjustments will be made by the pattern over North America during the next several days which will allow building cold in Canada and pieces of it to be delivered to New England. We are not about to plunge into a pattern of persistent cold just yet, however, as a “wavy rope” jet stream off the Pacific and moving across the US prevents that for now. This pattern, despite being active, is not one that produce major storms, with the ones in this time period being of generally minor impact, like today’s wet weather event. As I said previously, the track of today’s low pressure area is one that would many times bring snowfall to much of the region, but with the lack of cold air, this will not be the case. However with rain in the vicinity already, there may be some pockets of icing in portions of central MA and southern NH where temperatures, especially in valley locations, are hovering around the freezing mark. By late in the day, however, low pressure wrapping up south of New England and dry air already pressing in from the north will cut off the precipitation in many areas to the north and west of Boston and they will dry out while a more concentrated band of moderate to briefly heavy rain may occur in eastern CT, RI, and southeastern MA. This will not be hanging around, however, and these areas will also dry out later this evening. As that low pulls away and intensifies Sunday, and high pressure builds in from the west, the squeeze-play between the two will bring a gusty north to northwest wind and there will be just enough instability around for a few snow showers to be about as colder air moves in. As the wind settles and high pressure moves overhead we’ll find ourselves with a colder than average but more tranquil day on Monday, but we’ll already be noticing high cloudiness increasing ahead of the next system. You probably have been hearing hype about this system for several days now, as it was shown as a more significant system on model guidance previously. However, I and others have stated that model guidance often presents a fair to poor performance in a split flow jet stream pattern, and has issues with where and when to phase streams, what to do with one stream or another, among other things. The reality of this system coming late Monday night and Tuesday is that it will be a relatively minor system, but may deliver some snow, enough to slick up some roads, at a time when many people would be using them early Tuesday. And with the colder day just ahead of it, it would allow the impact of even minor snow to be a little more than what we saw in the system of last Thursday, when the ground was warmer. However, even that impact will be fleeting as milder air will work into the region during Tuesday, and we’ll likely see any snow going over to mix and rain before ending. That may not be the end of the story, however, as another batch of energy still has to translate eastward across the region Tuesday night into Wednesday and will generate another low pressure area that will bring some additional rain and snow. With marginal temperatures for this system we’ll have to wait a little bit to realize the details and impacts, but it is not going to end up being a major event.
Forecast details…
TODAY: Cloudy. Periods of rain, may briefly freeze on some surfaces in central MA and southern NH this morning. Highs 38-45. Wind light variable this morning, NE increasing to 10-20 MPH except 20-30 MPH Cape Cod and Islands during the afternoon with some higher gusts.
TONIGHT: Southern NH, northern and central MA dry out with breaking clouds while overcast and rain continues early to the south and east before ending late evening. Clearing pre-dawn. A few patches of black ice may form. Lows 30-37. Wind N to NW 15-25 MPH with higher gusts, strongest MA East Coast including Cape Cod.
SUNDAY: Mostly sunny to partly cloudy. A passing snow shower possible mid afternoon on. Highs 38-45 morning, falling back through 30s afternoon. Wind NW 15-25 MPH with higher gusts likely.
SUNDAY NIGHT: Partly cloudy with a risk of a passing snow shower early, then clear. Lows 18-25. Wind NW 15-25 MPH with higher gusts early, diminishing overnight.
MONDAY: Sunshine followed by increasing cloudiness. Highs 28-35. Wind light variable.
TUESDAY: Cloudy. Pre-dawn snow except mix South Coast with minor accumulation. Morning mix to rain showers. Isolated rain showers afternoon. Lows from the middle 20s to lower 30s. Highs from the upper 30s to middle 40s.
WEDNESDAY: Cloudy with rain/mix/snow likely morning. Variably cloudy with snow showers possible afternoon. Temperatures generally stead 30s to lower 40s. Becoming windy late-day.
DAYS 6-10 (JANUARY 10-14)
Windy, cold, dry January 10. Tranquil, cold, dry January 11. Unsettled weekend January 12-13 with snow/mix/rain possible but not looking like a major storm at this point. Drier weather returns January 14.
DAYS 11-15 (JANUARY 15-19)
Low confidence forecast as we’ll be looking for a transition from the Pacific flow pattern to one that should be a little more dominated by a broad trough and more northwesterly flow. But forecasting the evolution of this pattern and its timing is very difficult at this point. The period probably starts and ends dry with a passing system of rain/mix/snow somewhere in between.