This spring is looking good for the Pacific Northwest and the Mid Atlantic.
You can check flows across the continent and see what's running at any time in color coded fashion at The River Gypsies' Flows Page
For checking snowpack out west, the most handy single link I've found is this one.
You can pull down the first menu to select a state, then just click the "create report" button. You'll want to look for the column of Snow-Water equivalent as percent of normal to see where the various areas stand.
Norhtern West Virginia has been flowing pretty good lately, and Washington State has been going too - although it's still pretty cold up there and not the best camping weather. It looks like they will have a great summer.