Driver power window stuck in DOWN position

Last weekend while doing a few store runs, the driver Power Window got stuck in the OPEN position, that means it was open for a while when driving, and then it started to rain. I raised the window about half way at first, then jogged it down just a tad. When at drive thru window at fast food joint, I lowered the window, then went to drive away (while raining) and it was STUCK fully open!!! Finally got it UP a few inches at a time. Is that the window motor or switch? what if rain dripped on the left armrest where switch is located? Had a NEW driver window motor installed in summer of 2012. Now it's stuck again.

Probably window regulator.