I was thinking, there might be TWO reasons why the answer might be ‘YES.’
The air is denser, therefore more ‘viscous’ (wrong word perhaps, we’re talking about air, not liquid.) It takes more energy to push through.
Winter conditions (without snow) usually means stronger winds blowing the vehicle about.
What do you think?
Weather conditions do affect “drag”. Wind occurs in all seasons, so I’d guess that is a wash season to season. Snow won’t affect drag, but as it builds up on the road is does increase rolling resistance.
Dirt on cars affects drag, you don’t see dirt on a race car at the start of any race. Since cars might be “dirtier” in the winter there would be a slight increase in drag.
While winter air is more “dense” it also has less moisture in it. So, does winter dry air have more or less drag compared to summer hot and humid air? This is a physics experiment, which may or may not have been done. I think you’d find an answer by talking to pilots and those that fly in the air frequently. Affect on cars is minimal.
There are so many other things that kill fuel economy in winter that air condition can be ignored. Thicker oils and greases, the requirement for more fuel for starting and warm up are just two. Resistance from rolling on snow and the buildup of ice in the wheel wells are two more.
Barometric pressure is the measure of the density of air and it remains about the same in winter and summer. So i guess the amount of aerodynamic drag depends on whether you have a headwind or a tailwind and the wind speed, not the season.
But, isn’t cold air more dense then warm ? Would that mean more air resistance in cooler weather, assuming wind speed was not a factor ? In golf and baseball, the ball travels less distance on cooler days because of this. All you golfers should get this one right.
Did any of you see the show (myth busters) where they test out many crazy things. The one I am thinking of is the one that they covered a car with golf ball dimples and found that it give the car better mileage. Ordinary dirt did nothing.
Yes it does. I checked to see how fast my vehicle would run in December and then in July and there was about 1.35 MPH difference. Ha ha ha .
“Ordinary dirt did nothing” shhhh Jos. That’s my excuse for not frequently washing the cars; they get better mileage. Keep the truth to yourself please. :=)
If you want to test the dimple theory, a hailstorm might do the job.