SMA ENCOUNTERS WX AND DURING 180 TURN BECOMES SURROUNDED BY CLOUDS. DECLARES EMER DUE HIGHER TERRAIN IN AREA. VECTORED TO ARPT.

Narrative

I WAS ON A VFR FLT FROM LARAMIE; WY; TO GRAND JUNCTION; CO. I HAD RECEIVED A WX BRIEFING AT XA30 AM FROM CASPER FSS. IT DESCRIBED THE WX AS CLR WITH SLIGHT TO MODERATE TURB. I FILED THE VFR PLAN AND LEFT LARAMIE ENRTE TO GRAND JUNCTION; CO. AROUND EAGLE; THERE WERE SEVERAL SCATTERED CLOUDS BUT MUCH HIGHER THAN THE TERRAIN. I WENT TOWARDS THE CLOUDS. IT APPEARED THEY WERE DROPPING VERY RAPIDLY. I STARTED EXECUTING A 180 AND FOUND MYSELF IN THE CLOUDS AS THEY DROPPED IN THE SKY AS IF SOMEONE PULLED THE PLUG. AS I COMPLETED MY 180; I FOUND MYSELF IN THE CLOUDS THINKING I WOULD QUICKLY FLY OUT OF THEM; BUT I DID NOT. THE PLANE BEGAN TO BE BUFFETED BY WX AND ICE BEGAN BUILDING ON THE PLANE. AT THAT TIME; I DECIDED I NEEDED TO DECLARE AN EMER AS THERE ARE SEVERAL 13000 TO 14000 FT PEAKS AND I WAS AT 12500 FT. ZDV PICKED ME UP ON THEIR RADAR AND DIRECTED ME TO AN ARPT AND I LANDED IN GLENWOOD SPRINGS; CO. I BELIEVE WHAT CAUSED THE PROBLEM WAS THE UNSTABLE WX MASS. I HAVE FLOWN THIS RTE MANY TIMES AND HAVE NEVER SEEN THE WX REACT AS QUICKLY AS IT DID. I BELIEVE WHEN I STARTED MY TURN; I WAS WELL CLR OF THE CLOUDS AND WOULD BE IN A SITUATION WHICH COULD HAVE BEEN PROGRESSED SAFELY. THE WX CHANGED TOO QUICKLY RESULTING IN HAVING TO DECLARE THE EMER.