Dry paws in cats can be due to cold whether, rough surfaces or deficiency of oil in the diet. You should purchase a diet which contains oil especially omega 3 fatty acids which can protect cat's skin from being dry and also effective for dry paw. You can also purchase paw treatment lotions or paw treatment rub from the pet store and use on the dry areas of cat. This will help you a lot. If there are no improvements by use of these things then take your cat to vet.
From reading comments and doing research online I found that Cat paws might dry out due to the type of litter you use. There may be more reasons but if you don't feed your cat anything unusual, and isn't sick, then I'd say its the cat litter. Some people use the pine litter but complain of the odor.You could also try organic cat litter. The pine litter helped the dry paws including the ointment that was put on the paws 2-3 times a day. You should try that.