Locally, we've got the typical spring rains lately, but also have had a few warm (high 50s, low 60s) sunny breezy days which will help dry the trails out. I stayed away from Allegrippis this weekend, but plan on hitting it next weekend unless we get showers later in the week. I'm thinking trails will be good to go starting next weekend, although they might be a bit leafy yet until the traffic picks up and grinds them up. A lot of the trails have a stony soil so it dries out pretty quick, and with no leaves on the trees it helps.
Raystown lake is a very popular vacation destination so a lot of private and public campgrounds are in the area. Sounds like you are coming a bit early in the season, so some may not be open yet depending on your actually trip dates. (2) campgrounds are right on the Army Corp. of Eng. grounds that house the trails. Susquehannock is basic camping/no running water sites. Seven points is much larger and has power, showers, etc. Both are on ReserveAmerica. A few hotels exist in nearby Huntingdon as well - about a 15 minute drive from the trailhead.
If you're looking for other activities - rent a canoe or kayak and spend some time on the water at Raystown Lake. If you are looking for more riding opportunities, Rothrock State Forest is nearby - lots of riding options, but nothing like Allegrippis. Rothrock is more traditional PA singletrack - rocky, technical, ridges, etc, riding - probably more what you're used to up in NY.