Figure 1 depicts the surface observations at 5:00 pm EDT, which shows a trough of low pressure extending from a low pressure in western Massachusetts. This trough was likely responsible for thunderstorm initiation, which ultimately led to this tornado.

The Stoughton Junction, MA EF0 tornado of May 9, 2013 impacted Norfolk County in Massachusetts. According to NOAA (2020), the EF0 tornado caused no fatalities or injuries, but caused $30 thousand dollars in property damage. The tornado touched down near Washington Street at 4:31 pm EDT. The tornado travelled for 0.38 miles and had a maximum width of 50 yards.
Sources
NWS Weather Prediction Center Surface Analysis Archive. (2017). Surface analysis 21Z Thu May 9 2013. Retrieved from: https://www.wpc.ncep.noaa.gov/archives/web_pages/sfc/sfc_archive.php
NOAA National Centers for Environmental Information (2020). Storm Events Database. Retrieved from: https://www.ncdc.noaa.gov/stormevents/