New England Weather This Week: Scorching Start, Cooler End

This week will feature two distinct weather patterns. One will bring scorching heat and humidity while the other will bring clouds, showers and much cooler temperatures.

MONDAY & TUESDAY

The much-discussed heat dome over the east coast will be in full- force over New England to start this week. Extreme heat warnings remain in effect for much of southern and central New England through Tuesday. For Monday, a couple factors may come into play that keeps temperatures and humidity from reaching their full potential. First, an area of high pressure may build offshore, which would allow for a stiff sea-breeze.

This would keep the coastal plain from pushing well into the 90s. This could potentially keep eastern Massachusetts from reaching the 90° mark. Areas away from the coast (outside of the mountains and northern Maine) will likely surge well into the 90s. The other factor will be the atmosphere's ability to mix down drier air aloft. This would cap dew points in the 60s to low 70s. While still humid, this could prevent humidity from reaching their highest possible levels.

On Tuesday, the heat will likely peak for most in central and southern New England. Temperatures aloft will peak and the sea-breeze will be mitigated by a stronger westerly flow. With nearly full sun, high temperatures will once again be well into the 90s with some spots potentially reaching the 100° mark. High humidity will bring feels-like temperatures into the 105-110° range.

Below: AIFS showing potential temperatures Tuesday afternoon:

Later Tuesday, a cold front will begin to approach northern New England. This front will eventually bring relief to New England, but will likely remain hung up in Canada through the day, allowing for another hot day across all of New England. It may allow for isolated thunderstorms across northern New England in the afternoon, but lift and shear will be weak. Dry air aloft will also make thunderstorm development hard, but strong heating and high instability may allow for a few storms. Any storm that manages to form could become strong.

WEDNESDAY

On Wednesday, that cold front will slowly sag through New England as the heat dome begins to get suppressed to the south and west. This will bring lowering temperatures and humidity. Wednesday will act as a transition day from a heat dome to a stalled frontal boundary set up. While this will be a dry frontal passage for most, a few pop-up showers or storms will be possible in the afternoon. Cloud cover will also be increased.

THURSDAY & FRIDAY

The cold front will stall to the south of New England for the remainder of the week. This will bring cooler, cloudier and more unsettled weather back to the region. Mostly cloudy skies with scattered shower chances will be around both days. As of now, shower coverage looks to be generally higher on Friday than on Thursday. Shower coverage will likely be highest across the northern tier of New England.

This new setup will also allow for a more prolonged period of an onshore flow, which will keep temperatures down as well. Highs both days will likely be in the 70s for most. With more clouds and showers around, Friday will likely be a notch cooler, with some areas possibly struggling to break out of the 60s.

Below: Euro showing temperature departure from average Friday afternoon:

WEEKEND

The same general setup from late this week will still be around heading into the weekend. On Saturday, a more organized area of low pressure will likely ride along the frontal boundary, bringing another round of scattered showers and thunderstorms to the region. At this point, it again looks like northern New England will see generally more by way of rain over the weekend than southern New England, though this will depend on the final location of the low pressure system.

Below: Current weather map for Saturday morning (June 28):

Current trends show the stalled frontal boundary lifting back northward during the day Sunday. This would bring a gradual trend toward less clouds and showery weather from west to east during the day. This would also allow for temperatures to begin to tick back up. Whether this happens, or if the front remains to the south keeping the region cloudier and cooler, remains to be seen. Trends will be watched throughout the week.