I don't think humidity in and of itself is bad or good, as a fine haired curly, I definitely know it effects my hair. I watch the weather report to know what clothes to pick as well as what hair products to use. Mid to high humidity means lots of humectants and cone free conditioning. In the winter, humidity rarely goes above 30%, so no frizz, but major potential dryness, so lots of water based moisturizers sealed with oil.
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