VFR FLIGHT BY THE NON-INSTRUMENT RATED PILOT INTO INSTRUMENT METEOROLOGICAL CONDITIONS (IMC), AND HIS FAILURE TO MAINTAIN SUFFICIENT ALTITUDE (OR CLEARANCE) FROM RISING TERRAIN. FACTORS RELATED TO THE ACCIDENT WERE: FAILURE OF THE PILOT TO UPDATE HIS WEATHER INFORMATION AT THE EN ROUTE STOP, THE ADVERSE WEATHER CONDITIONS, RISING TERRAIN, AND THE PILOT'S LACK OF INSTRUMENT EXPERIENCE.