Just a clarification. Moist air is LESS dense than dry air.

Dry air is mostly diatomic Nitrogen - wt= 28
some diatomic oxygen - wt= 32
a percent or two of other gases.

MOIST air is the above with the addition of H2O
2 hydrogen = 2
1 oxygen = 16
Total wt/molecule = 18

replace any of the molecules in dry air with water, and the density goes DOWN.

I've found flying here in MN, I've been okay just opening the high speed up a bit to compensate for the increased air density. It also REALLY helps to keep the fuel warm - I just keep it inside the home then the car - some people have actually warmed the whole jug in a tub of hot water.

Tim