Figure 1 depicts the surface observations at 2:30 am EDT, which shows a cold front across the U.S. Midwest and a warm front across the Great Lakes. The cold front moved east throughout the day and triggered thunderstorms, which reached Massachusetts in the late-evening hours of November 21st. These thunderstorms were responsible for three F2 tornadoes across the state.

The West Newbury, MA F2 tornado of November 21, 1956 impacted Essex County in Massachusetts. According to NOAA (2019), the F2 tornado caused no fatalities or injuries, but caused $25 thousand dollars in property damage. The tornado touched down in Essex County west of Church Street at 11:40 pm EDT. The tornado travelled for 0.8 miles and had a maximum width of 17 yards.
Sources
NOAA Central Library. (2019). U.S. Daily Weather Maps. Wednesday November 21, 1956 [PDF]. Retrieved from https://library.noaa.gov/Collections/Digital-Collections/US-Daily-Weather-Maps
NOAA National Centers for Environmental Information (2019). Storm Events Database. Retrieved from: https://www.ncdc.noaa.gov/stormevents/