Bring your boat and overboots this weekend!!! The weather is calling for some nasty rain showers... But we need the rain so that part is OK, it is just the heavy showers that will suck. Plan for lots of mud and even some ice still up high which was reported on a NE hiking website. The ice should not be a major issue, it will mostly be near the summit, and you probably won't need crampons, just watch your footing. When I was up on Slide a few weeks back there was minimal ice till 3500ft, then lots of it at the summit. Now with the weather and such, only the summit areas appear to still have some ice.
As for overnight parking, I am not sure what the official policy is, but I have never been bothered in the past, YMMV...
Catch you later..
Kevin