This week will be dominated by frontal boundaries, and the systems that ride along those boundaries. This will bring multiple rounds of showers to New England starting tonight and lasting through at least Thursday. The heaviest of the rainfall amounts are looking to stay just south of New England.
Expected rainfall through Friday, showing the greatest chance for multiple inches of rain staying just to the south of New England:
MONDAY
A cold front that dropped through New England on Sunday will remain over, or just south of, southern New England for much of Monday. High pressure will build into New England behind this front, bringing a quiet and seasonable day with partly cloudy skies, though clouds may increase in the afternoon.
Later in the day, the stationary cold front will begin to lift back north as a weak warm front. This could trigger some isolated showers in the afternoon for southern New England, but with dry air aloft and ridging in place, showers coverage should be pretty limited. Rain chances will increase and become more widespread during the overnight hours as an area of low pressure moves to the south of New England.
The heaviest of the rain will likely fall in two areas: one will likely stay just to the south of New England while the other develops along the front lifting into northern New England. Rainfall amounts of a half an inch to inch and a half will be possible across the foothills and mountains of northern New England with lesser amounts farther north and south. The immediate south coast and especially Cape Cod and the Islands could also see an inch plus.
TUESDAY
The steadiest of the rain from the overnight system will move through New England Tuesday morning. After the bulk of the rain moves moves away by midday, a general drying trend will begin. It won't be totally dry in the afternoon as scattered showers and thunderstorms will likely pop up, mainly across northern New England. There may be breaks of sun in the afternoon between the pop-up showers. Highs will be kept cooler with morning rain and clouds, topping out in the 70s for most.
HRRR showing potential weather Tuesday morning (1st image) and Tuesday mid-afternoon (2nd image):
WEDNESDAY & THURSDAY
Wednesday will remain unsettled as another disturbance rides along the stalled frontal boundary near southern New England. This system may take a similar track to Monday night to Tuesday's system. This would keep the highest rainfall amounts across the southern third of New England. Wednesday will likely see scattered showers and storms throughout the day, peaking in the early afternoon.
The risk for severe thunderstorms Wednesday is low, but if the system trends farther north, this risk would increase. Highs this week will be coolest on Wednesday with plenty of clouds and showers around, but humidity will be elevated as tropical-like air is pumped into the region. There will be a chance of heavy downpours developing across southern New England, which could lead to isolated poor drainage flooding. This threat decreases farther north.
On Thursday, the main trough over the Great Lakes will begin to push northeastward. This will help lift the stationary front through New England as a warm front, putting New England into a "warm sector" type setup for the day. This will bring yet another round of unsettled weather for the day. The system's cold front will cross New England at some point during the day Thursday.
The atmosphere will continue to be primed for potential downpours and heavy rain as it remains moisture-rich. This will extend the potential flash flood threat into Thursday. This comes as multiple rounds of downpours will be possible during the day. Shower activity throughout the week may prime the ground for flooding as well. The Weather Prediction Center currently has all of New England in the "marginal" category (level 1 of 4) for excessive rainfall on Thursday.
There may also be a conditional severe weather threat as well. This extent of this threat will be determined by the amount of instability that can build within the warm sector of the system as well as the timing of the cold front. Thursday may be the most impactful weather day of this unsettled stretch, but we'll be watching the trends through the week as the system could weaken as it passes through New England.
FRIDAY
The weather looks to begin to calm down on Friday as the cold front from the main trough clears New England. It is likely that the trough will remain close enough to support lingering shower chances on Friday, but a drying trend is likely throughout the day. Friday will likely begin a general warming trend as the weather settles down.
WEEKEND
High pressure currently looks poised to move into New England for the weekend. This will bring back sunnier skies and warmer temperatures. This upcoming weekend may end up being rather similar to this past weekend with warm temperatures, dry conditions and lower humidity. This will hinge on the timing of the trough and ridge moving through late this week, especially for Saturday. With high pressure potentially overhead, a sea-breeze will be possible, keeping the coast cooler.
Weather map for Sunday morning:
Comments