Heatwave likely in much of New England – NBC Boston

A severe thunderstorm warning was issued for parts of New Hampshire until 4 p.m. and in central Oxford County, Maine, until 4:30 p.m.Severe thunderstorm warnings were issued earlier in the day for parts of northern Vermont. The latest severe weather warnings can be found here.

It’s hot! We’re experiencing the hottest temperatures of the year and summer hasn’t officially started yet – or has it?

Technically, the answer is yes for us scientists and no for those who follow the stars. Meteorological summer began on June 1 and lasts until August 31. Astronomical summer officially begins on Thursday at 4:50 p.m. EDT and ends on September 22.

For anyone confused, meteorological summer includes the warmest months of the year – June, July and August – while astronomical summer is when the sun’s rays reach the northernmost latitude, the Tropic of Capricorn, on Thursday of the summer solstice. This is also the day when daylight is at its longest: 15 hours, 17 minutes and 14 seconds in Boston!

A heat warning is in effect for much of the region through Thursday evening, except for the southern New England coast, eastern Maine, and the Cape and Islands, where temperatures will range from 21 to 25 degrees. In the remaining regions, temperatures will rise to 35 to 40 degrees in the afternoon, with heat indices just above 38 degrees. A heat warning is in effect for parts of southern New Hampshire and inland Maine through tonight, as the extreme heat and humidity will push heat indices to nearly 40 degrees!

Wednesday afternoon will be fairly dry across most of the region, but there may be a few showers and thunderstorms, especially in Vermont, New Hampshire and Maine. Some of these could also reach northern Massachusetts on Wednesday evening. Some of these could be heavy to isolated severe.

Thursday will be the last day of extreme heat, with temperatures in the 35-40s and high humidity. Expect more scattered showers and thunderstorms to develop in northern New England during the afternoon before reaching northern Massachusetts in the late afternoon. Some of these showers may be heavy to heavy.

Friday will see big changes as the winds come stronger from the northeast with a cold front coming in through the back door. It will remain muggy, with temperatures reaching highs of 27-29 degrees, falling to 21 degrees on the coast with a strong northeast wind by the afternoon. So far, it looks like the Celtics’ championship parade will be mostly dry, with isolated showers and thunderstorms holding off until late afternoon. At least the heat will be over then!

Temperatures will remain warm at over 27 degrees towards the weekend, but there is a risk of showers and thunderstorms in the afternoon.