From NWS Boston along with the forecast minimum temps and wind chills:

[Historic Arctic Outbreak Feb 13-14 2016] The dangerously cold airmass that will invade the region Fri into early Sat will be the coldest temps seen in Southern New England since Feb 13-14 2016. Worcester dropped to -16 & Boston fell to -9; which were the coldest temps at both sites since 1957!