Good morning! I am in a time crunch this morning so this won’t be a long post at all.
The areas that were under a heat advisory yesterday are under one today as well, again until 7 PM. Highs will be a hair cooler, but still in the low to mid 90s with a few scattered upper 90s readings possible in the Merrimack Valley. Skies will be mostly sunny and winds will be SW at around 5-10 mph for much of today.
This combination of high heat and humidity will produce heat index values of 100-105, and heat exhaustion and heat stroke are possible for those who spend significant time outdoors tomorrow (especially if exerting physical work). If working outside, take frequent breaks and drink lots of water. If possible, stay in an air conditioned area, stay out of the sun, and check in on relatives and neighbors (particularly the elderly).
This graphic is on the National Weather Service’s national heat safety site, and it nicely describes the differences between heat exhaustion and heat stroke.
There will likely be some scattered thunderstorms this afternoon and early evening. Heavy rain and lightning are likely in any cell that develops, but an isolated to scattered severe storm may occur. Damaging winds will be the main threat, and while it is not likely, an isolated tornado cannot be ruled out. If a tornado does occur, it will probably be short-lived and weak (and more likely than not to be in NH or Maine).
When thunder roars, go indoors. And if a tornado warning is issued, take shelter in a basement or an interior room on the lowest floor of a sturdy building and avoid windows.
As I noted heavy rain has a solid shot of occurring in any cell, and there may be some street flooding in susceptible locations as such. Turn around, don’t drown when encountering flooded roads.
Some small hail is a low possibility and large hail is not expected at any point.