My palm is smaller than yours, but used to lose leaves like yours does. While it's very important to allow the soil to dry between waterings, I have found that I was actually allowing it to become too dry. Now that I'm watering slightly more often, the plant is losing leaves less often. Perhaps that's something you could try with yours?
Sorry this is so short, but a friend is repeatedly texting me to come into my back yard and look at the snake she found.
ETA: It was a sweet little baby garter snake, green with yellow stripes and about as big as a standard pencil.