ngyak! may fogging ako

I'm quite sure na it's properly sealed kasi equal ang fogging ng both headlights ko. pinacarwash ko na rin yun at wala namang pumasok na tubig. umuulan kasi ng ginawa yun. ngayun, kapag gabi at malamig, nagfog sya sa mga gilid (not always tho). will removing the bulbs and letting the air out fix this? (provided that the surrounding air is not humid)
I'm just afraid that the fogging may stain the lens and bring up the need to disassemble it again.
I guess this is not a problem in the states since hindi humid ang air.
meron bang magaling sa science dito? hehehehe.