I'm really interested in using a tidally locked planet as the setting for a new fantasy piece of mine. Here's what I have so far: The only habitable area would be the twilight zone (hehe). The dark side would be completely frozen over, with a dense atmosphere. The sunny side would be like Utah, or the Sahara with a thin atmosphere. Due to one side of the planet being hot and the other cold, there would be fierce storms, and all wind would be warm because of the high pressure air moving to the low pressure air. I have a feeling the sunny side would be full of gigantic mountains and valleys because the water that would normally be covering them would be evaporated. Due to the massive ammounts of evaporated water, there'd be a LOT of cloud cover. Would it rain all the time? it would probably be very humid. Anyways, these are my thoughts about it. Any insights would be greatly appreciated. Also, assume that the planet is about twice as big as Earth, and that the distance and size relative to its sun are the same ratio of Earth to our sun. Basically, its another Earth that happens to be tidally locked to its sun. Thank you for any response!