By Scott Stransky
The average high in Boston this time of year is 47�F (8�C). For the duration of this week, we can expect temperatures to exceed this value. Why is it going to be so warm here? One major reason is the position of the jetstream.
The jetstream is a band of fast moving air in the upper levels of the troposphere. Typically, these winds blow from west to east and act as a conveyor belt, transporting storms and airmasses along. These high-speed winds normally separate the cooler, polar air from the warmer, more tropical air. During the summer, the jetstream is further north than it is during the winter, so we might expect the jet to be somewhat south of us at this time of year. In our current state, however, the jetstream is well to the north of us.
So how long will these temperatures last? A storm system will move through at the end of this week, leaving us in a much colder airmass. Next weekend, we will be lucky to make it to a high of 40�F (4�C).
Today: Mostly cloudy. High 50�F (10�C).
Tonight: Mostly cloudy. Low 40�F (4�C).
Tomorrow: Mostly cloudy. High 53�F (12�C).
Tomorrow night: Mostly cloudy. Low 47�F (8�C).
Thursday: Sun and clouds. High 60�F (16�C).
Thursday night: Possible rain. Low 50�F (10�C).