I know we get cold in the winter I saw people planting a big needle palm 1 meter tall. the winter did not do any thing to it but the summer almost killed it. We been having to many supercells and the summer was so hot that it reached 98 F it could have been higher then a F1 tornado hit it and someone spotted a F5. Do you think are climate is good for palms because I doubt it. But now its so warm that there is forest fires everywere. We get to much bad storms all the time.
i think oklahoma is fine for palms, but if its the tornadoes/wind/heat thats killing them, try planting them in more shaded or windblocked areas, or keep them potted and pull them inside on days like those. -alex