help! Mexican Fan Palm turning brown
We recently moved into a house that has a nice size Mexican Fan Palm (about 25 feet tall). It seemed to be doing great until the last month or so. I've noticed that the palm leaves are turning brown at the tips on all the palms (bottom to top). I thought maybe it was due to the cold weather/winter season, however several other people in our neighborhood have palms and none of them seem to look this way. I've been reading up on diseases/problems with them, and my best guess is that it might be a potassium deficiency (??). I've attached some links to pictures. Any help would be greatly appreciated.
Photos of tree: