I'm officially an "Autumn Texan" now.:) (Winter keeps me busy in my tax office up North). I highly recommend checking out the Hill Country area - Fredericksburg, Austin, San Antonio and points in between. In future years I hope to move around between these areas and the more popular Southern enclaves mentioned in an earlier post. Texans are friendly and it is a very RV friendly state - lots of parks to choose from. Buy the State Park pass and get reduced fees for camping. The Texas SP system offers full hookups and large sites - example Cedar Hill - a real nice area south of Dallas.
weatherbase.com provides a very nice hi/lo chart for 12 months for any city you choose. Parts of Texas might get a dusting of snow and occasional freeze.