I vote for gelling. I suspect that the fuel available in FL is definitely not specified with the same (low) pour point as northern fuels, and your unusually cold weather has caused it to gel.

The fact that it starts OK tells me it's not something mechanical, unless as a long shot your lift pump is going south. If the problem remains after the weather warms up, I'd suspect the lift pump.

Rgds,
Chris W.
'95 E300D, 304K