For many of us over northeastern MA, we received a nice treat yesterday afternoon and last night as some cooler and less humid air flowed in with the passage of a backdoor cold front. I was predicting that the front could back down into the Essex County coastal plain but it traveled even farther and stalled over eastern Worcester County. It was a gift because it definitely rejuvenated me as it was much more comfortable with all the work that I had to do around my home. It was so great to open up all the windows and use fans to exhaust the stuffy, stale air resulting from the previous muggy days. Oh well. It was pleasant but only temporary as the boundary retreats to ME as a warm front today. The refreshing air departs this morning and the 3-H weather takes control for several days. As mentioned in my blog of yesterday morning, July, on average in Boston, has 6 days at 90 degrees or higher. It is possible that the city will record all of them in a row starting tomorrow! There is, however, an upper level disturbance on its way that would produce more numerous showers and thunderstorms on Monday. This activity could prevent the temperature from striking 90 but it will be very close. That system will exit Monday night but additional showers and storms are likely much of next week as several impulses are poised to pounce on the region especially on Wednesday and Thursday. So it is still possible to get a 90 on Tuesday too. Regardless, it is going to be a heat wave because it will be at least 3 days over the magic mark of 90. The discomfort level will mount in this air mass that will contain high to oppressive humidity. Through the period, Cape Cod will be cooler in the lower to middle 80s. Overnight lows will be mainly in the range of the upper 60s to middle 70s. There is hope that refreshing air will finally arrive from southern Canada at the end of next week.
The most important portion of this forecast package deals with the weather for our Independence Day celebrations. Nobody wants a repeat of last year’s evacuation during the thunderstorms. Presently, it appears that just a few scattered boomers will exist later tomorrow afternoon and early evening mainly well north and west of Boston. Check out this Planning Guide if you expect to attend the Boston Pops Fireworks Spectacular or watch the entire celebration on WBZ-TV from 7-10pm. Boston’s highest temperature on record occurred on July 4 in 1911 at 104 degrees! Thankfully, the temperature at the Esplanade will not be record-breaking but certainly sizzling enough as it maxes out at 91 tomorrow around 3pm with middle 80s by 7pm and near 80 at the conclusion of the fireworks that will run from 9:30-10pm. The southwesterly wind will blow at 10-20 mph with a few higher gusts in the afternoon then decrease to 10-15 mph in the evening. The humidity will be high to oppressive with dewpoints in the upper 60s to lower 70s. There will be a mix of sunshine and clouds throughout the day. Just keep an eye to the sky especially if you live farther and farther north and west of Boston. There could be just a few stray storms on the prowl.
Gullywasher rains produced some serious flooding and many road washouts in parts of western NH yesterday. Doppler radar estimates of 1 up to 4″ of rain fell across much of that region. A Flash Flood Watch is currently posted through this evening by the National Weather Service for areas well northwest of the Boston area. I reiterate that those who are traveling, hiking, climbing and camping near rivers, creeks and streams especially in mountain valley areas today and tomorrow should be aware that flash flooding can be a real threat. Be ready to suddenly seek higher ground under any tropical drenching downpours.
For holiday vacation week plans, you will find daytime temperatures about 10 degrees or so lower on much of Cape Cod as the southwesterly wind freshens to 10-25 mph providing some ventilation as it blows in from the Atlantic Ocean. It will also be cooler on the ME coast especially near and downeast of Portland. Unlike yesterday when the cooler surged down the coast from ME, the heat will be driven to the coast from the west-southwest over the next several days so you will not find relief at east-facing beaches unless you head into the water which is 60-65 degrees. Boaters over the inland lakes mainly north and west of Boston should carefully monitor the sky for any storm development. Boomers are more likely over mountainous locations over the weekend so be cautious of lightning bolts and flooding rains in a few places. It will be hot in the mountains too but, of course, cooler at the higher summits like Mt. Washington which will top out in the range of 60-65. Visibility will be cut due to haze.
Todd Gutner posts his blog early this evening and I shall return early tomorrow morning.
Have a happy and safe long holiday weekend!