Winter in Pittsburgh

[Jinx]

Good day all. Jinx is out of the country.
I am looking for some general advice.
First major snow of the season.

We have about five inches of snow in Pittsburgh.
2003 base Boxster.daily driver, driven this past
Weekend. Summer performance tires.
Car is at times in a enclosed garage other
Times outside but covered.
I plan on driving it weather permitting
Every second or third day.

My question is is it advisable to start the
Boxster and leave it run until it reaches
Operation temperature. I have access
To a area to run the car, but it is a
Relative smooth and level but unplowed
grass Area.

Thank to all in advance for your help
Bill