The big question here is what is your tolerance for colder weather. There are a lot of places along the gulf coast from Florida to south Texas that attract the northern RV snowbird crowd. I live in southwest Louisiana about 80 miles inland and it does get cold here, but rarely does it get all that cold, though last winter we did have a 40 year low of about 13F two nights in a row, or more typical winter lows are 3-4 nights in the mid 20's, very rarely staying below freezing more than 24 hours in a row, snow that sticks to the ground only happens about every 5 years, and rarely last for more than a few hours, and is typically only a fraction of an inch. Daytimes highs in January can typically range from 40's to the 70's, with highs typically somewhere in the 30's for 1 or 2 days every couple of weeks after a cold front blows through.
As you get closer to the gulf coast one sees more and more of a moderating effect, 50 miles south of here where my sister in law lives (25-30 miles from the coast on the southside of Lake Charles, LA), it rarely drops below freezing,
See the information on this local weather station site to give you an idea of what I am talking about https://www.weather.gov/lch/climate particularly https://www.weather.gov/images/lch/climate/normals/JanuaryLowTemps.png and https://www.weather.gov/images/lch/climate/normals/JanuaryHighTemps.png
as you can see from that last link, there are places that average 8-10 degrees warmer along the coast than where I live in January. If I were to pick an area of Louisiana for winter RV life it would be in the heart of Cajun country around Abbeville or New Iberia
If you want 80F+ nearly every day then the options are south Florida, south Texas around the RGV and southern Arizona, if you can live with average highs in the 60's and 70's then there are a lot of other options.