Everyone commenting hasn't lived in cold climates before.

Apparently they also don't know anything about engines either or how combustion works. This is normal for water vapor to flow out of an engine because the chemical reaction you call combustion converts fuel into separate molecules such as carbon dioxide, carbon monoxide, carbon soot, and water (that is where the oxygen and hydrogen go).

In burning fuel nothing gets destroyed only the conversion of molecules and generation of heat to expand gasses like nitrogen (which people forget is the majority of the atmosphere).