Milder Days & Low-Impact Weather on the way for New England

New England's weather over the next several days will be mainly influenced by a rather zonal flow. Zonal flow (when the jet stream has a stronger west to east motion and lays flatter across the United States) tends to promote near average temperatures as deep troughing or ridging is absent. In this specific case, however, the Pacific-North American Index has been tilted positive. When the Pacific is the main influence in weather across the country, it leads to a milder flow and temperatures moving across the country.

This will allow for some milder days in New England's future. We said "rather zonal" above as the overall flow pattern in the upper-levels will be more quasi-zonal than fully zonal in the coming days. While the jet stream will generally be free of deep ridges and troughs, it won't be lying perfectly flat, either. This will lead to changeable weather and temperatures as we head through the week leading up to Thanksgiving.

Below: 500mb flow pattern on Saturday afternoon, showing a quasi-zonal flow and closed low over the desert southwest:

While this setup does allow for some milder days for New England, it will not be notably mild given the time of year. New England is, naturally, the farthest away from the Pacific across the northern tier of the United States, so the mild influence will be more pronounced to areas west of New England. In New England, afternoon temperatures will likely hang around the high end of seasonable levels in the coming days. 30s and 40s will dominate for the north while 40s and 50s will dominate for central and southern areas.

Below: Temperature departure from average next Monday, showing much of the country above average, with the mildest conditions remaining to the west of New England:

Zonal flow can often lead to a generally active, but low-impact, pattern as weak waves of energy moving through the fast upper-level flow. This will continue to be the case, but waves of weak low pressure are currently poised to move well north of New England. This will keep forcing for showers (snow and rain) mostly to the north of New England. The next system in this stretch will pass to the north Friday into Saturday morning.

This will drag a cold front across the region, which could ignite some showers from west to east Friday afternoon through Saturday. An area of low pressure may form along this front near or south of New England, but a majority of precipitation from this is expected to remain offshore. Another system will pass to the north Monday into Tuesday, bringing another round of scattered showers, mainly to northern New England. Both of these systems are weak and will likely deposit little by way of rain and snow.

Below: Current 5-day precipitation outlook:

The main feature to watch for New England will likely arrive around the middle of the week. An area of low pressure will likely form across the desert southwest around the start of the week. This system will likely push eastward across the southern tier of the United States. This system then looks to get ejected northeastward, moving up the east coast. The system is currently favored to undergo at least some phasing with a northern stream system moving north of New England around the same time.

This will likely lead to a period of widespread precipitation. The system is currently poised to arrive in New England by the middle of the week, with the three major models (Euro, GFS and CMC) currently all agreeing on a Tuesday evening/night or Wednesday arrival. With that said, timing of the system can certainly change, no matter how much agreement is currently seen.

There likely also won't be much polar air interaction. With milder air generally expected across the region next week, this looks to be a widespread rain-maker for the region rather than the potential for widespread wintry precipitation. Thermal profiles leading up to the event support plain as the primary precipitation for a majority of the region as well. The one thing to watch will be the potential for low pressure development in the Gulf of Maine.

Should this occur during the storm, especially near the beginning, it could lead to cold air damming and some mixing potential for northern areas. Overall, the system's duration and intensity remain a question. The system is currently favored to clear out by Thanksgiving morning, but this is very low confidence. Overall, Thanksgiving could see lingering showers with an increasing breeze as the system's cold front moves through the region.