Forecast: Hot Temps Today — But Humidity To Drop Tonight

Boston finally reached 90 degrees Sunday for the first time since last September, making this year the fifth-longest wait on record for reaching this milestone.

Today will be the hottest day of the week — perhaps even the hottest day this month — as many places reach the mid 90s. There is a chance Boston does hit 90 degrees again Tuesday, and if this occurs, it would make for an official heat wave.

The last heat wave was a seven-day, 90-degree stretch set on the same week in 2013. Climatologically, this is our hottest period of the year.

Although this week begins on a hot note, it ends on a cooler and drier one. In spite of the heat today, you’ll notice a drop in the humidity by the end of the day and a much better night for sleeping ahead. Tuesday is very warm, with highs in the upper 80s to near 90. But, with low levels of humidity, it won’t feel as badly as the past few more humid days.

A cooler flow of air will take over starting Wednesday, with temperatures staying in the 70s over the upcoming weekend in many places. This is amazing to be forecasting such pleasant temperatures and low humidity during a time which is more typically very hot and humid.

If you are on vacation this week, there won’t be much if any shower activity. There is a chance for a scattered shower Tuesday evening. There might be some possibility of a shower this weekend, especially over northern New England, but these look scattered and insignificant, with a strong chance they'll be out of the forecast later this week.

Here’s an interesting note on the rainfall that fell across much of the west coast this weekend. San Diego recorded 1.69 inches of rainfall as of last evening, and this not only breaks the record for July, it was higher than all the previous July months for 101 years, combined! That’s a super historic rainfall event. However, although a seemingly large amount, it didn’t do much for a multi-year drought.

Today: Becoming mostly sunny and hot. Humidity levels will fall during the day. Highs 91-95. Cooler Cape/Islands.

Tonight: Partly cloudy, drier. Lows in the mid to upper 60s.

Tuesday: Mostly sunny, and very warm. Highs 85-90.

Wednesday: Sunny, and seasonably warm. Highs in the low to mid 80s.

Thursday: Sunny, with a high near 78-81.

Friday: Mostly sunny, with a high near 77-80.