New to the forum, hope I've got this in the right place.

I have a 2008 Superduty with 60k miles, purchased new, never had any problems with it, until now.

We live in upstate NY, lots of snow and crappy roads this year. I drove it in a snowstorm a couple weeks ago, front end was crusted with an inch of of snow and road spray.

Went to start the truck the next morning and had no power at all - no dash, no key chime, no fuel pump, nothing - completely dead. Figured I would have to jump the truck, so I opened the hood and as soon as I did that the power came on, lights and key chime, dash everything . Strangest thing I've ever seen and hasn't happened since.

Ever since then, the battery light comes on. No light right after starting then after 20-30 seconds, the battery light comes on and stays on. I put a voltmeter on the batteries, both read 12.6 before starting , read 13.5 with truck running at idle, jumps up to 14.6 when turn on lights at fast idle, then drops back to 13.5.

I'm at a loss to try to figure out the "no power" incident and now the battery light staying on as the alternator seems to be within specs.
The local ford dealer charges an 'arm and a leg' for service and I need all I have - Has anyone else experienced this or have any ideas?
Thanks