THE PILOT, WHO WAS ATTEMPTING TO FOLLOW THE FREEWAY THROUGH MOUNTAINOUS TERRAIN, WAS FLYING VFR UNDER LOW CEILINGS. AS HE FLEW THROUGH LOOKOUT PASS AT ABOUT 200 FEET ABOVE THE GROUND, HE ENCOUNTERED AN AREA OF FOG, SNOW AND RAIN. AFTER INADVERTENTLY ENTERING THE CLOUDS, THE PILOT CLIMBED IN A NORTHERLY DIRECTION UNTIL THE AIRCRAFT IMPACTED A RIDGE AT AN ALTITUDE THAT WAS ABOUT 900 FEET HIGHER THAN THE PASS.