Narrative:

Shortly before departure; I called FSS and received a WX briefing. After departure; I contacted approach for flight following to ZZZ1; while cruising at 11500 ft just north of ZZZ2; I encountered some widely scattered cumulo nimbus and stratus which was easily navigation'ed around with ample VFR clearance. Around this time center called and advised me ZZZ1 was 2500 ft overcast. I informed them I would continue to ZZZ3 which was clear and 10 and would add 20 mins to the flight. As the flight progressed; visibility reduced to approximately 6 mi in haze and the number of cumulo nimbus increased; making it more difficult to remain on course. Northeast of the ZZZ VOR; I called center and initiated a climb to remain clear of clouds but soon found myself unable to continue climbing or maneuvering to remain VFR as towering cumulo nimbus were building in every direction. Just before cloud penetration; I leveled the nose and informed center I would not be able to maintain VFR. Upon entering the cloud; my aircraft immediately began to accumulate ice so I asked for a descent to 6000 ft. The controller queried me on my ability then declared an emergency on my behalf and cleared me to 9000 ft. I was handed off to approach control and cleared lower and given direct ZZZ4 which was reporting VFR. I broke out of the clouds at 4100 ft 3 mi southeast of ZZZ5. After a few mi in VFR; I spotted ZZZ4; thanked the controller; and landed safely. Just prior to entering cloud; I felt the safest action was to lower the nose; stabilize the aircraft; and tell ATC what is happening; when ice began to form my thought was to descend to warmer air. Upon encountering more than scattered clouds; I should have completed a 180 degree turn towards better WX. 2 days after the event; I contacted my flight instructor to begin training for the instrument rating.

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Original NASA ASRS Text

Title: A VFR M20 PILOT ENCOUNTERED IMC ENROUTE AND BEGAN PICKING UP ICE. ATC DECLARED AN EMERGENCY FOR HIM AND VECTORED HIM TO A SAFE LANDING.

Narrative: SHORTLY BEFORE DEP; I CALLED FSS AND RECEIVED A WX BRIEFING. AFTER DEP; I CONTACTED APCH FOR FLT FOLLOWING TO ZZZ1; WHILE CRUISING AT 11500 FT JUST N OF ZZZ2; I ENCOUNTERED SOME WIDELY SCATTERED CUMULO NIMBUS AND STRATUS WHICH WAS EASILY NAV'ED AROUND WITH AMPLE VFR CLRNC. AROUND THIS TIME CTR CALLED AND ADVISED ME ZZZ1 WAS 2500 FT OVCST. I INFORMED THEM I WOULD CONTINUE TO ZZZ3 WHICH WAS CLR AND 10 AND WOULD ADD 20 MINS TO THE FLT. AS THE FLT PROGRESSED; VISIBILITY REDUCED TO APPROX 6 MI IN HAZE AND THE NUMBER OF CUMULO NIMBUS INCREASED; MAKING IT MORE DIFFICULT TO REMAIN ON COURSE. NE OF THE ZZZ VOR; I CALLED CTR AND INITIATED A CLB TO REMAIN CLR OF CLOUDS BUT SOON FOUND MYSELF UNABLE TO CONTINUE CLBING OR MANEUVERING TO REMAIN VFR AS TOWERING CUMULO NIMBUS WERE BUILDING IN EVERY DIRECTION. JUST BEFORE CLOUD PENETRATION; I LEVELED THE NOSE AND INFORMED CTR I WOULD NOT BE ABLE TO MAINTAIN VFR. UPON ENTERING THE CLOUD; MY ACFT IMMEDIATELY BEGAN TO ACCUMULATE ICE SO I ASKED FOR A DSCNT TO 6000 FT. THE CTLR QUERIED ME ON MY ABILITY THEN DECLARED AN EMER ON MY BEHALF AND CLRED ME TO 9000 FT. I WAS HANDED OFF TO APCH CTL AND CLRED LOWER AND GIVEN DIRECT ZZZ4 WHICH WAS RPTING VFR. I BROKE OUT OF THE CLOUDS AT 4100 FT 3 MI SE OF ZZZ5. AFTER A FEW MI IN VFR; I SPOTTED ZZZ4; THANKED THE CTLR; AND LANDED SAFELY. JUST PRIOR TO ENTERING CLOUD; I FELT THE SAFEST ACTION WAS TO LOWER THE NOSE; STABILIZE THE ACFT; AND TELL ATC WHAT IS HAPPENING; WHEN ICE BEGAN TO FORM MY THOUGHT WAS TO DSND TO WARMER AIR. UPON ENCOUNTERING MORE THAN SCATTERED CLOUDS; I SHOULD HAVE COMPLETED A 180 DEG TURN TOWARDS BETTER WX. 2 DAYS AFTER THE EVENT; I CONTACTED MY FLT INSTRUCTOR TO BEGIN TRAINING FOR THE INST RATING.

Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.