Electrical System Issue?

81DAWG

Yesterday evening I pulled out of my driveway to run out to the grocery store. I had gone less than 1/2 mile and was still in my neighborhood when the lights on my dash started to flicker and my engine started to sputter. After a few seconds the engine died. I tried restarting but it barely turned over as if the battery was dead. This happened in front of the house of a neighbor who happens to be a diesel mechanic. He had a fully charged jumper box that we hooked up to my battery and tried to start the engine again. Same thing, with the fully charged jumper box the engine would turn over weakly for a second or two, and then stop. We pushed the Z off the road into his yard, put a couple of cones out that he had and left it there for the night to deal with today. Before I call AAA and have it towed to the dealership, anyone out there have any ideas what is going on?