Extreme heat likely to break records with 90s forecast all weekend

By Terry Eliasen, Meteorologist, WBZ-TV Executive Weather Producer 

BOSTON – Graduations, proms, weddings, Little League games – there is a LOT going on this weekend. For those who circled this weekend on the calendar weeks or months ago, my guess is you were thinking, “just please don’t rain,” or “please give me a warm day and not some cloudy day in the 50s.”

This probably wasn’t on your list of concerns – 95-to-100 degree heat.

Well, here we go. We will not only challenge daily high temperature records both Saturday and Sunday, but we will likely also be close to all-time record highs for the month of May! That record of 97 degrees was set 152 years ago on May 26, 1880. I’m fairly certain that nobody reading this blog can say they remember that!

Let’s take a closer look at the weekend, where it may be hottest and where you can go for some relief.

SATURDAY

The morning won’t be that hot! We have a complex for showers and thunderstorms that will move through our area after midnight. 

The rain should be over before dawn Saturday, but I think there will be some leftover cloudiness for a good portion of Saturday morning, particularly in eastern Massachusetts. So, the heat will get off to a bit of a slow start. Many early baseball games or graduations may actually happen under cloudy skies. By late morning and midday, the wind will veer to a more south-southwesterly direction (from southeast in the early AM) and the clouds will be departing. When this occurs, temperatures will soar quickly.

Take a look at this projected timeline of high temperatures in the Boston area, most of MetroWest and the Merrimack Valley:

7 a.m.: 60-64
10 a.m.: 66-70
1 p.m.: 84-90
4 p.m.: 90-95

The record in Boston on Saturday is 93 degrees. No doubt that many towns along and west of I-95 will surpass that mark. Boston should, but there is always a chance, being right on the water, that a slight change in wind direction could keep the city a few degrees lower than the max potential temperatures.

Looking to beat the heat? Head south! High temperatures within 5-10 miles of the South Coast will remain in the 70s. Head out east on Cape Cod or to the Islands and highs will be in the 60s! Can’t promise a ton of sunshine down that way, but it will feel a lot different.

SATURDAY NIGHT

Stuffy. Stifling.

All areas away from the South Coast and Cape will stay very warm and muggy overnight. Temperatures likely won’t drop below the 70s for a large part of our area. With dewpoints in the mid to upper 60s, this is not a night to open the windows. We could challenge record high minimum temperatures (currently 70 degrees on May 22 in Boston set in 1921)

SUNDAY

With a higher “launching pad” temperatures will rise much more quickly than Saturday. We will cross the 90-degree threshold around or before noon in many areas.

With nearly full sun and southwesterly winds pumping in the heat we have the potential to reach the upper 90s in most of Middlesex, Essex, Suffolk and Norfolk counties as well as most of southern New Hampshire.

Records will tumble early in the day Sunday and as long as the southwest wind direction holds, Boston could challenge the all-time record high of 97 degrees for the month of May. I would not be shocked to see a couple of towns in the Merrimack Valley reporting 100 degrees Sunday afternoon.

Once again, relief from the heat can be found along the South Coast, Cape Cod and the Islands. The southwesterly wind direction will keep temperatures in the 60s and 70s much like Saturday.

SUNDAY NIGHT

A cold front will approach from the west. You are likely thinking that given all the heat and humidity we could be in for some raucous thunderstorms. However, at this point it looks like most of us will get a dramatic change in airmass and not even get a drop of rain. There just isn’t a lot of support for any severe weather (locally) Sunday night or early Monday. It will certainly remain quite warm for the first half of the night, but you will feel a huge change when you wake up on Monday. Dewpoints will drop into the 40s and temperatures will fall back to more seasonal levels.

NEXT WEEK

Looks a bit more typical of what you would expect in late May. Perhaps a bit above average (in the 70s), through Wednesday with no major weather concerns. We may briefly spike back into the 80s ahead of a cold front and some rain later in the week. As for Memorial Day weekend, no major heat signals right now. Odds favor cooler and perhaps wetter conditions to start and warmer to finish. More to come on that in the days ahead.

Please take the heat this weekend seriously. If you have to be outside, try to stay in the shade as much as possible. Stay hydrated and be sure to check on the elderly and your pets!

For updates all weekend long, stick with WBZ-TV, CBS Boston News and CBSBoston.com