It sounds like Mineral Oil is the best oil to seal out humidity in high dews (and seal in moisture during low dews) in porous hair:

THE NATURAL HAVEN: The best moisturiser - mineral oil *cough*

Mineral oil: don't knock it 'til you try it!!

What do you all think?
Upper Michigan Dews
3a ~ Fine ~ High Porosity ~ Normal Density

NoPoo: JC Cleansing Cream
Rinse Outs: SS:PRT, CJ Repair Me, CJ Argan
Detangler: KCKT
Leave-in: CJ Repair me
Stylers: UFDCM, BRHG
Refreshers: Batiste (dry shampoo) on the roots & UFDCM everywhere else

iHerb Discount Code: SAF007