SMA DEVIATING WX PENETRATES ARSA WITHOUT CLRNC.

Narrative

I DEPARTED FROM OSHTABULA COUNTY ARPT FOR A DIRECT FLT TO MARSHFIELD; MA. DEP WAS AT :06 EDT. THE CEILING WAS SCATTERED TO BROKEN WITH TOPS AT 7500 FT. NAV ENRTE WAS PRECISE TO THE WINDSOR LOCKS AREA WHERE I COMMENCED A DSCNT. IT WAS NECESSARY TO DEV TO THE S TO STAY CLR OF CLOUDS (2000 FT SIDE; 1000 FT UNDER; 500 FT ABOVE). UPON DSNDING THE ACFT ENG BEGAN TO RUN ROUGH AND AFTER CHKING I FOUND CARB ICE TO BE THE CULPRIT. ONCE CLRED THE ENG RAN PROPERLY AGAIN. AT THIS TIME I SPOTTED WHAT SHOULD HAVE BEEN NORWOOD AND S WEYMOUTH ARPTS AND DEVIATED TO THE S TO NOT INTERFERE WITH THEIR TFC AREA. IT WAS AT THIS TIME THAT THE COAST BECAME VISIBLE AND IT WAS ALL WRONG FOR THE MARSHFIELD AREA. I WAS TOO FAR S. UPON REACHING THE COAST I REALIZED I MUST HAVE VIOLATED THE PROVIDENCE ARSA AS MY ALT WAS 2000 MSL. FROM THERE I CONTINUED UP THE COAST TO MY DEST AT MARSHFIELD. THE CARB ICING CAUSED ME ENOUGH DISTR TO GO OFF COURSE. I ERRED IN NOT BEING CONSTANTLY AWARE OF MY POS BY RELYING SOLEY ON VISUAL REFS AND MAGNETIC HDGS TO RECTIFY THESE SHORT COMINGS I PLAN TO WORK ON AN INST RATING TO MAKE ME A MORE PROFICIENT PLT. I TRULY REALIZE THE SEVERITY OF SUCH INCURSIONS AND KNOW THAT I IN THE FUTURE WILL DO WHATEVER IS NECESSARY TO AVOID THEM.