Here in CT they change the gas blend in November. The winter blend is less expensive (or so they say) than the summer bled, but it drops gas mileage by about 2-3 MPG. I went from 33 MPG average over the summer to 29-30 MPG now.
Check around to see if your state changes the gas blend for winter. That might be the problem.
2012 SEL Hatch
- Blue Candy