I've noticed on my '92 that the front windows always go up fine regardless of the conditions but if it's cool outside (prob. anything below 60) or if it's just rained/high humidity that it goes down slow and you can tell the motor is straining. Because of this I avoid using my front windows (rears are fine).
I'm assuming it's something to do w/ the tracks but I've looked and can't see any problems, so maybe it's electrical.
I know on some Accords ('94-'97 I believe) that what appears to be a window motor going bad can actually be the window switch itself, bad contacts, whatever.
I'm not sure if that actually helps or not

h: