That was about a month ago. This morning it was about 5°f but I plugged it in for a couple hours before I attempted to start it. Usually it sits in the garage overnight anyways.
The difference between summer and winter-blend gasoline involves the Reid Vapor Pressure (RVP) of the fuel. The EPA says conventional summer-blend gasoline contains 1.7 percent more energy than winter-blend gas, which is one reason why gas mileage is slightly better in the summer