New England's weather will be rather stagnant over the next week or so, with little change from one day to the next. This stagnant weather will involve several days of persistently cold temperatures (but not Arctic) and scattered snow showers mainly across the north and mountains at times, amounting to little, if any, accumulations. Breezy conditions will also stick around for much of the next week, adding an extra bite to the chilly air.
The main driver of this stuck weather pattern is a strong and expansive ridge over Greenland. This high pressure is sitting in place and refuses to move. This is causing a backlog of weather systems over the United States and Canada that have nowhere to move to with the exit blocked by the ridge over Greenland. Just to the northeast of New England, the New Year's Day storm remains stalled and cutoff. This is the main driver of the persistent wind gusts and scattered snow showers.
To the west of New England, there is an expansive area of Canadian high pressure over south-central Canada and the northern plains of the United States. This will help keep funneling cold air into New England through the week. There is also a building ridge across the west coast, keeping the east in a trough. All of this build-up is mainly thanks to the large block over Greenland.
The block over Greenland and the cutoff low pressure system to New England's northeast has set up a Rex Block situation. A Rex Block is a blocking pattern that involves an area of high pressure located directly north of an area of low pressure. This setup blocks the low pressure system from travelling east and north along the jet stream, preventing a timely exit. In this case, the New Year's Day storm has nowhere to go and remains swirling near New England, keeping the region in a trough.
As with all blocking patterns, this one will be stubborn and slow to break down. The block over Greenland will remain in place more or less through the first half of January. The cutoff low will continue to remain to the east of New England, likely retrograding back westward, closer to New England, around midweek before sliding back eastward and away from New England as it breaks down.
Below: Flow pattern Sunday afternoon (though this general setup will remain in place from now through the middle of next week). You can see the position of the high pressure directly north of the low pressure, resulting in a Rex Block scenario:
This setup results in a persistent northwest flow, resulting in a cold air mass remaining over New England. Cold air masses tend to be dry air masses. For the most part, this will be the case with little by way of precipitation expected over the next week. With that said, the cutoff low will create broad cyclonic flow and allow for several shortwave disturbances to move through New England.
This will result in scattered, light snow showers, mainly in the mountains. One of these weak disturbances may drop into southern New England, bringing flurries farther south Sunday morning. Moisture will be very limited across New England this week, so any snow showers will be brief and light. Other than that, expect dry conditions with variable clouds.
Below: Current 7 day precipitation forecast:
The only exception to the "brief and light snow showers" will be across the Green Mountains, particularly the northern Green Mountains, as saturation remains higher. This will allow for more persistent upslope snow showers through mid-week. A westerly flow off the unfrozen Lake Champlain will provide additional moisture for snow showers (similar to lake effect events on the Great Lakes, though feet of snow will not fall in this case). You can see elevated moisture across the northern Green Mountains on the graphic above compared to the rest of New England.
An organized storm system is poised to get shoved to the south of New England by this cold air mass early next week. This storm will result in 4-8+ inches of snow for portions of the Mid-Atlantic. There remains a chance that the northernmost snow showers will get into southernmost New England, but accumulations would be very light and limited to southern Connecticut, Rhode Island and the South Shore.
Below: Probability of at least 2 inches of snow from now through Tuesday morning:
As far as the winds go, gusts will remain persistently around the 20-35mph range from now through late next week. Generally speaking, gusty winds will be highest and most noticeable across southern New England. The winds will relax during the overnight hours before picking back up after sunrise. The calmest day will be Monday, when gusts will be more in the 15-25mph range, with the higher end of the scale occurring in eastern Maine. The winds will pick right back up on Tuesday.
These winds will generally remain below damaging levels. The highest impact will be persistently low wind chills across the region. With high temperatures anywhere from the upper teens north to low 30s south through this week, the wind will add quite an extra bite. Lowest wind chills during this time will hang around the -10s for the north and mountains to the single digits in southern New England. These winds will help keep overnight lows from bottoming out.
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