Dewpoints have been falling through the day. It has turned into a wonderful summer afternoon with even a cooling sea breeze at the coast lowering temps into the lwr 80′s, while inland temps have been around 86-89 degrees.
With high pressure overhead, drier air, light winds and clear skies…we are in store for a gorgeous summer night with temps dropping down to 60-65 in Eastern MA…with lows in the 50′s in western valleys. More sunshine for Wednesday with temps once again climbing towards 90 with moderate humidity.
As high pressure sinks south and off the coast of New England, a heat ridge currently in place across the midwest will be shifting east. This will direct the hottest airmass of the summer towards the east coast. This is not just a really hot airmass. It is also very humid. In the midwest temps, are ranging from 95 to 105 with dewpoints 75 to 82. Hutchinson, MN had a dewpoint of 85 today! This is the source airmass which will be directed into the northeast for Thursday & Friday with breezy SW winds. Temps will be so warm through the entire column that it will be just too warm to storm.
Temps will be climbing into the mid 90′s Thursday and edging near 100 degrees by Friday. Mix this heat with dewpoints climbing to the mid 70′s and you are talking about an extremely hot airmass. The Heat Index will range from 100-110 in the peak of the heat Friday. It will be critical to at some point find some air conditioning and stay cool and well hydrated. Keep a close eye on the babies, pets and elderly who are the most vulnerable in this kind of heat.
A weak cold front begins to push through on Friday but does not get off the coast until late Saturday. Saturday should still be quite warm in the 90s before more seasonal air arrives for the second half of the weekend. An upper low will move across Northern ME and direct much cooler and less humid air into the region by Sunday with temps in the lwr-mid80s. Building high pressure at the surface from Canada should provide abundant sunshine and comfortable conditions through Monday.