New England weather this week: Active

While there will be breaks in the rainfall this week, a stalled cold front and multiple waves of low pressure will bring rounds of thunderstorms and rainfall throughout the week.

MONDAY

A cold front will drop into northern New England through the day Monday. A disturbance will ride along the front, allowing for yet another round of thunderstorms. With the cold front and disturbance across northern New England, it will be northern New England who sees the most numerous storms in the afternoon. More isolated/spotty storm chances will exist in southern New England for the evening hours as the front drops south.

Photo byNew England Storm Center

Ingredients will be in place for any storm to turn severe for a time, but a full-fledged severe weather outbreak is not expected. These ingredients include sufficient lift from the cold front and moisture from the level heat and humidity. Shear and instability will also build. Damaging wind and large hail are the threats within stronger storms. There will also continue to be the potential for torrential downpours.

Photo byNew England Storm Center

Timing will hinge on the cold front's timing, but it looks like storms will break out across northern New England (away from the coast) by early to mid-afternoon, first in Vermont before spreading east-southeast. A secondary round of storms will be possible for northern New England in the evening.

Southern New England will likely see much spottier coverage in the evening as forcing for storms will remain across northern New England. There is a chance for strong to severe storms in southern New England as well, but the question will be if enough energy will allow storms to develop there in the first place.

WRF-ARW showing potential weather around mid-afternoon today:

Photo byHRRR/Tropical Tidbits

The other issue with these storms outside of the potential severe threat, some localized flooding will also be possible. This threat will be greatest in the areas that saw multiple inches of rain on Sunday and localized flooding. These areas include the Northeast Kingdom, White Mountains, northern Maine and southern New Hampshire.

TUESDAY & WEDNESDAY

On Tuesday, the cold front that marched through New England will have stalled just south of the region. This will allow a eave of low pressure to ride along it Tuesday afternoon before passing to New England's south Tuesday night into Wednesday morning. There will be a chance for scattered showers during the day for the south coast (and morning showers leftover from Monday's system), but the bulk of rain from this system will come Tuesday evening through the overnight hours.

Photo byNew England Storm Center

As of now, with the cold front expected to stall just south of New England, it looks the heavier downpours will remain along the south coast of New England. There is a chance that the heaviest downpours remain just offshore. Rainfall amounts drop off heading farther north. Getting into northern New England, much drier air may result in a sharp cutoff in showers. Exactly how far north showers get will be determined by exactly where the cold front stalls out.

HRRR showing potential weather early Wednesday morning. There remains a spread among guidance with some models showing the rain pushed farther south than this:

Photo byHRRR/Tropical Tidbits

As of now, the best chance of upwards of an inch of rain will be the Mass Pike and points south. Depending on if the heaviest downpours can make it to shore, there will be locally higher amounts in Connecticut and Rhode Island. The Weather Prediction Center currently has areas generally south of the Mass Pike in the "slight" category (level 2 of 4) for excessive rain. It's worth noting that just to New England's southwest, across New Jersey and Pennsylvania, there is a "moderate" (level 3 of 4) chance.

Photo byNew England Storm Center

Heading into Wednesday afternoon, a drying trend across New England should take shape as high pressure builds in from the northwest. A general north and east flow will keep New England on the cooler side despite the drying weather. Highs will remain in the 70s for the remainder of the week.

Photo byNew England Storm Center

THURSDAY

There's little doubt Thursday will be the nicest day of the week. High pressure looks to remain in control despite the frontal boundary remaining stalled to New England's south. There will likely be scattered shower chances for the southern third of New England in the afternoon with the front nearby, but much of New England is looking mainly dry. Temperatures will remain on the lower end, but more sunshine may allow it to be the warmest outside of Monday.

Weather map for Thursday:

Photo byWeather Prediction Center

FRIDAY & WEEKEND

Heading into late this week, there remains a large spread in what will happen. This stems from what the remnants of Hurricane Debby will do. The storm will likely stall out offshore of Georgia/South Carolina before making its way up the east coast this weekend. The track and timing of the storm late this week will become more clear after the storm makes it through Florida.

Photo byNational Hurricane Center

While the center of the storm will be well south of New England on Friday, a moisture plume could break off and head toward New England for Friday and/or Saturday. This would interact with the frontal boundary stalled to our south. This is a recipe for a period of steady to at times heavy rainfall. The Weather Prediction Center has southern and central New England in the "slight" category for excessive rain.

WPC excessive rainfall outlook for Friday. This will be modified and refined as confidence increases later this week:

Photo byWeather Prediction Center

Where exactly this band of steadier rain would set up remains to be determined, but wet weather will be returning to most of New England in some fashion at the end of this week, whether it be lighter, scattered showers or a period of steady, widespread rainfall. The level of rain over the weekend will likely be determined by where the actual center of the remnants passes, which remains uncertain.

Ensemble tracks for the center of Debby. You can see a broad range still exists:

Photo bytropicaltidbits.com