Oh Myrna, I feel your pain!! Lol!! Of course for me mineral oil is the only way to really combat humidity. I'm not sure how that would work for your low porous hair, but it's my miracle.
Jojoba and grapeseed work pretty well, but their effects don't last like MO. I still use them in good dews or days I won't be going out much and know I'll have a chance to wash again the next day. I've use MO with success on days where I'm outside in high dews for several hours, even.
I have the SM shine spray. I use it almost like a hairspray, and as a refresher. I use it on dry hair - I don't know that I've tried it on damp at all, actually.
I'm not sure if any of that helped, but that's all I can add to help, I think. :/
2c/3a/3b, Fine/med, Dense, high porous, & normal elas.
Lo-poo - Renpure Keratin, SMR, Giovanni SaS
clarifying - mix Johnson's H2T with low poo
Co-wash - Suave Nats. clar. or coco.
RO - GVPCB, Ion Eff. Care, TN.
LI - SMR, Cure Care, or RO
Seal - MO or Jojoba
DT - + honey, ACV, & EVOO to SM masque & GVPCB
PT - Gelatin!, CNPF
Styling - FSG, AIF, BRHG, LALS/PS, GF curl spray gel, SM Souffle/Smoothie, LOOB
Oils - MO!, EVOO, jojoba, GSO, SM Elixer, EVCO, VO5 Hairdressing