My 2013 Alaska trip fuel graph is based on percent change and should be a good guide to predict price variations and even actual future prices from a relative perspective.
Of course a major refinery shutdown would...
Generalizing on what AKsilvereagle said don't count on anything being open or available. We planned on staying at the first CG in Watson Lake only to find out 2 of the 3 GCs were closed. A email from Terri Church indicated that knew about the closures earlier in the year. Unfortunately they had not updated their online corrections nor did they by late fall.
Also right after we left a caravan booked the entire remaining CG.
We arrived early afternoon at a CG. Caravans have reservations and we wanted to arrive before most of the other campers.