I've got a royal & a coconut palm in Houston & i bring both ib when hits 40 degrees....Thad

I hear that there are some in phoenix, but i dont think that they like the extreme heat so they have to be careful when they plant them. But im not sure if this is true

Royal palms don't mind the heat as long as they get enough water. There is a huge one on the south side of the Arizona State Capital in downtown Phoenix. That area is much warmer than other areas during winter which helps keep it warmer, plus it is on the south side of a large building which gives it radiant heat at night. There are also a few out in Palm Springs, but granted they are not as common as other palms like queens and date palms.