Yes, of course it is! Curly hair is affected by humidity the most! It also tends to become a bit dryer in dry weather so you need to change your hair care routine and products accordingly.
During dry weather make sure to condition your hair a little bit more and maybe use a heavier leave in conditioner. As for humidity, you need to use a higher hold gel or use a diffuser so your hair dries faster. Also for some ladies, they might need to cut out any products that contain glycerin