Lots and lots of people disagree, so I'm not recommending this, but - during really low dew points (when the Frizz Forecast tells me my curls will be "limp"), I find products with...**Jaws theme here**...silicones, instead
of glycerin, seem to really help keep my hair from drying out. "Dimethicone" (an anti-humectant) in some stylers and "Amodimethicone" in my cleanser are my guilty secrets. I don't use silicone combos, or, as far as I'm aware, any silicones other than these two. I think they help seal in moisture and give some weight to my hair, so I don't have to walk around looking like a Sim that got struck by a meteor. (Sims 3 fans get it)
I have super dry hair, and I color it, which increases dryness. During low dew points, my hair resembles the looped side of velcro, only it's not that soft.
It knots and tangles and quite often the only remedy is chopping out the knots. My favorite "cg approved" products don't always make the cut when it's dry season, and somehow my hair is both limp, and frizzy, and it feels like frayed burlap.
Oddly, protein, which can really mess up my hair, doesn't seem to be as much of an enemy during low dew points. After trial and error I decided what was really causing trouble was glycerin. It's all right in small levels, or in highly highly moisturizing products (like Coffee Coco Curl Cream applied heavily
), but gels or creams that are glycerin-based definitely make my hair even drier.
Avoiding glycerin really seems to help, along with DTs at least
once a week and using extra leave-in.