Near record-breaking temperatures are coming to Massachusetts on Thursday, and perhaps on Friday as well. But the actual temperatures that might go into the record books don’t matter as much as the fact that it’s just going to be hot and humid this holiday weekend.
The heat wave should break Sunday or Monday.
A shower is likely coming Wednesday afternoon or evening, but it’s going to be so hot on Thursday and Friday that the atmosphere will be “capped.” That means the air will have less of an opportunity to rise, limiting clouds and any shower activity.
The humidity is not going to completely break for a few days — perhaps late in the weekend, perhaps as soon as Friday.
The next chance for showers and storms will be on Saturday, which is, of course, the Fourth of July. If any thunderstorms develop, it could affect festivities and fireworks planned for Saturday night.
There’s all sorts of ways to measure how uncomfortable the next few days are going to be. The dew points in the 70s, and the heat index — a combination of temperature and dew point — will be at or above 100°.
Another measure, called the global wet-bulb temperature, is the best way to predict possible heat-related illness. The forecast right now shows that the danger of heat-related illness will be high Thursday and Friday, especially in the afternoon.
Boston’s historical high temperature for Thursday, July 2 is 98° and the record for Friday, July 3 is 102°. The Fourth of July record is 104°, which is also the all-time record for any day in Boston, set back in 1911. Even with this week’s extreme heat, it’s unlikely that record will be broken.
There should be a bit of a break in the extreme heat next week, but more heat is likely later in the month. July is typically the hottest month of the year, so temperatures that are even just a little bit above average are going to be hot.
Use common sense to take care of plants, pets — and yourself and any kids. With all this heat, keep an eye on any containers with flowers and vegetables; they’ll rapidly dry out and need extra water.
Be careful taking dogs out, too: The asphalt can get extremely hot and burn their paws. And never leave an animal in the car.
Avoid strenuous outdoor exercise Thursday and Friday, especially between 9 a.m. and 6 p.m. That’s especially important with so many summer camps running this week; campers might need extra water.
