I second what Brucie said. Heck, I live in Texas now and I still go through my "winterizing" routine each year. I have a couple of bottles of water and a blanket, at the very least, under the back seat (not in the back end of the pickup--you might not be able to get out to it if you run into trouble). I used to always have a down sleeping bag in the truck, but have switched to the blanket in this climate. You hear about people here who ran off of the road and froze to death in bad weather just like you hear about it up north.

(Down here I fear the summers more--having an accident and cooking on the road surface before getting help!)

SRS