In the northwest, the higher elevations still have snowpack.  Neil2, you may
do better in the lower mountains you mentioned east.
 It was hot  in the Cascades for a few days, but it snowed again yesterday
down to around 4000', so I'd imagine the highcountry campsites might still
be snowbound or very wet and messy if they are accessable.  Be careful where
you drive..when snow has just gone, the ground is soft and fragile.
  Hey, I hear the Wal Mart lot in Bend is a big destination resort with the
RV crowd nowadays...(kidding.....)
  Don Hanson