Temperatures in Burnham fell to -1.2C on Saturday and did not rise above 3.9C on Sunday.
A Met Office warning of ice is in place for the Burnham-On-Sea area on Monday, and there is a possibility of sleet or light snow falling this week.
The Met Office says: “With temperatures falling rapidly through the evening and night, there is a risk of icy surfaces.”
It says the public should be aware of the risk of disruption to travel.