Should be fine although it rained in SW PA pretty good yesterday. Paw Paw to Cumberland on the C&O could be muddy if it rained there but passable as long as you accept you will get muddy. The campgrounds on the C&O are open but the water pumps are still locked and you may want to bring toilet paper.
Cumberland to Pittsburgh on the Great Allegheny Passage is crushed limestone rail trail so it will be in better condition than the C&O. Drains pretty good. Panhandle Trail (Pittsburgh suburbs to Weirton, WV) will be fine. First 7 miles are crushed limestone. The next 17 miles are paved asphalt. Finally, the last 4 miles as you enter West Virginia are crushed gravel but a bit rougher of a ride. That trail is run by four different groups/municipalities. The last chance to grab food/water is Burgettstown before you get to Weirton as it's pretty remote. I've never ridden in eastern Ohio.
How are you connecting from downtown Pittsburgh to Panhandle Trail? Most might take Neville Island to get on the western end of the Montour Trail, which then intersects with the Panhandle Trail but I've never done it. You could also exit the GAP at McKeesport and connect to the eastern end of the Montour Trail at Clairton. From McKeesport you take the Clairton Connector (
https://steelvalleytrail.org/map/) and avoid Pittsburgh altogether. I quite enjoy going all the way to Pittsburgh as the last miles into Pittsburgh are mostly paved with lots of bridges, trains and of course a cool skyline approach. it just depends what you want.
As John N. suggested, here's a good forum that is more localized to get you to Pittsburgh:
https://bikecando.com/forum.aspxThe counties you are going through in PA all went Green today (June 5) so you should be fine. At worst, there will be some minor restrictions (take out food, facemask).
Happy riding!
John