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We’re likely experiencing a fourth heat wave of 2021 this week

Children cooled off at the Children’s Fountain on the Christian Science Plaza in Boston.Jonathan Wiggs/Globe Staff

With a high of 91 degrees recorded at Logan Airport on Tuesday and two more days of 90-degree weather predicted for Wednesday and Thursday, many of us are now likely in the midst of the fourth heat wave of 2021. A local sea breeze at Logan Airport this afternoon might prevent this from being official.

Highs Wednesday afternoon will be near 90 degrees in most areas farther inland.WeatherBell

It’s been a very hot and particularly humid summer, however we won’t have all the statistics in for another week or so to know exactly where we land in the record books. The high humidity will continue through tomorrow along with an even hotter day. It may feel close to 100 for a couple of hours on Thursday as actual temperatures reach the mid-90s. I wonder how many of you who like summer weather are ready to be done with this mid-Atlantic-like climate this year?


There have been 21 days of 90-degree weather in Boston this year, with three official heatwaves.NOAA Data

I don’t expect to see any shower or thunderstorm activity today, but there may be an isolated storm Thursday amidst all the heat.

If you haven’t been to the beach this summer, today and tomorrow and even Friday provide ample opportunity to enjoy the warmest ocean water of the season.

Water temperatures in many areas are over 20 degrees Celsius or 68F.NOAA

A frontal system will pass to our south and East on Friday. Unfortunately this front isn’t going very far, so while dryer air will make it into the region on Friday, it’s not going to hang around very long.

Saturday on the cooler side of that front will be in the 60s and lower 70s with much less humidity. You’ll be able to turn the air conditioners off and even get a good night’s sleep Saturday night into Sunday with the windows open.

Dew points will fall into the upper 50s Saturday as the air mass changes.WeatherBell

There may be a couple of showers on Saturday with the proximity of the front so close, and a lot of clouds on Sunday for basically the same reason. The weekend forecast still needs to be refined to determine which of the two days is going to have the most sunshine, but right now neither day looks stunning.


That same front is going to turn around and come back north later Sunday, reintroducing warm and humid air and some unsettled conditions for the beginning of the work week.

After a couple of days of high humidity to close out August, another front is poised to come through in about a week. This particular system may put a more substantial end to the tropical air as we introduce meteorological fall and the first day of September.

The first week of September is forecast to be warmer than average.NOAA