As MIT welcomes the families of students and alumni for commencement and class reunions, the Boston “weather machine” is showing its notorious variability. A strong low-pressure system moved through the area yesterday, bringing heavy rain. During commencement this morning, the tail end of this system is pushing through the region. Conditions will be mostly cloudy. Showers are possible, with the weather models predicting about a 20 percent chance of rain. The likelihood of rain diminishes later in the day Friday and into Saturday.
After a week filled with temperatures in the 40s and on-and-off rain, Boston will finally see some nicer weather this weekend. Each day for the next few days will have a mix of sun and clouds with temperatures in the 60s. A mass of cold air high in the air column will move over the region on Sunday, creating an instability in the atmosphere. This system could generate showers and thunderstorms on Sunday afternoon. Depending on the strength of the instability, some forecasts have even predicted the slight possibility of hail.