I have noticed in the past on here that some people say that if you wind down the passenger window and leave the driver window up, you get less buffetting in the car.

It was a cool morning recently so I decided to test out the heater a bit with different window positions. I found the following with the heater set to the "open roof mode":

(1) Both windows up, heater on - a little heat goes around your legs.

(2) Driver window down, passenger window up - lots of hot air going all over your legs and lower body.

(3) Driver window up, passenger window down - seems to be the coolest, barely noticed any hot air around my legs.

So I found that (2) was keeping my body the warmest (except for my head).

 

What about both windows down?

 

its common knowledge that 2 works best and get a beanie!