New England weather this week: Hot start; relief incoming eventually

This week will start off with more of the same for New England in what has been a sweltering July. Heat and especially humidity relief will come at the end of the week as a stronger cold front than what we’ve seen as of late will move through the region.

MONDAY-WEDNESDAY

A strong ridge of high pressure planted over the Atlantic Ocean will continue to pump excessive heat and humidity into the region amid a west-southwesterly flow. Temperatures during the first half of the week will feature more widespread 90s (with 80s in the mountains). While Sunday saw high pressure overhead, which allowed a weak and slightly drier northwest flow, the southwest flow will bring back the more tropical-like humidity levels.

The heat and humidity will combine to create feels-like temperatures into the upper 90s to low 100s. This will be some of the hottest weather since the mid-June heat wave, though feels-like temperatures should still be lower than that heat wave, when some areas saw upward of 110°+ heat index values. Heat advisories are in effect for a good chunk of New England during this time frame. Wednesday may be slightly cooler with more clouds around.

Photo byNew England Storm Center

Without a ridge of high pressure directly over New England, there will be chances for shower/thunderstorm activity each day. On Monday and into Monday night, this will come as a weak disturbance approaches the region this afternoon and crosses overnight. With the heat and humidity in excess, CAPE values (measure of instability) over 1,000 and an approaching system to provide some energy, thunderstorms will likely bubble up. Coverage will likely be more limited rather than widespread.

There is a low chance for some storms to become strong to severe, but this threat is also very limited as lift and shear (2 main ingredients for severe weather) will be weak. More storms will be possible Tuesday afternoon as another quick disturbance passes. The setup will be similar to Monday, but increased shear may allow for more numerous storms and some severe storms in western New England. The bulk of the severe weather is expected to stay in New York. Storms will weaken as they push east in the evening.

Potential weather Monday afternoon (1st image) and Tuesday late afternoon (2nd image):

Photo byWRF-ARW/Tropical Tidbits

Photo byHRRR/Tropical Tidbits

Heading into Wednesday, a cold front will approach, which will provide forcing for another round of scattered thunderstorms in the afternoon and evening. The timing of storms, and the level of potential severe weather, will hinge on the timing of the cold front. As of now, the timing appears more favorable for scattered severe weather across southern and eastern areas.

The Storm Prediction Center has nearly all of New England in the “marginal” category (level 1 of 5) for severe storms on Wednesday, but this will likely get fine-tuned as the day gets closer. The trend has been for a later start time, with eastern areas potentially not seeing storms until later in the evening.

THURSDAY & FRIDAY

New England will see the cold front pass through New England by Thursday morning. Some lingering showers may be possible in the morning, especially if the cold front keeps trending toward a later arrival. This front will bring down both heat and humidity. By the afternoon, dew point levels will be in the 50s to low 60s for New England. Humidity falls further on Friday. 

Photo byNew England Storm Center

An expansive high pressure building to the west of New England will provide a drier west-northwest flow with more seasonable temperatures. Overall, this setup should provide some extremely pleasant weather to end the week. Highs will be dominated by the 80s rather than the 90s. This setup will also allow for much more pleasant overnight lows in the 50s and low 60s.

Photo byNew England Storm Center

WEEKEND

As of now, high pressure looks to generally be in control for New England this upcoming weekend. A secondary cold front may drop into New England at some point. Overall, a warming trend may ensue after Friday, but, at this point, it doesn’t look to warm back to the levels seen early this week. 

Weather map for Saturday morning:

Photo byWeather Prediction Center