Getting up to engine temperature

This is only my second winter with my 2011 F150, with the 5.0, and I didn't notice this last winter if it was the same.

I have a 25 minute drive to work all but the last 5 minutes are highway. It was 33 degrees this morning.

After almost 20 minutes the temperature gauge had barely budged off C and the fuel economy seemed particularly bad. But in the last few minutes the temp came up about 1/4 of the gauge, which still seems low, and the fuel economy improved to about normal.

Does the 5.0 have a tendency to warm up slowly and run cool? Or should I hook an OBD gauge up to it, and if it reads low consider replacing the thermostat?