SMA CLBS INTO SAN TCA WITHOUT CLRNC.

Narrative

I DEPARTED VFR FROM MYF ENRTE TO BULLHEAD CITY. I TRACKED THE 076 DEG RADIAL OUT OF MISSION BAY TO CLR ME THROUGH THE TCA. THE WX; HOWEVER; DETERIORATED SIGNIFICANTLY AND I HAD TO TURN BACK TO BETTER WX CONDITIONS TO GET AN IFR CLRNC. I MADE A 180 DEG R TURN AND HEADED BACK TO MYF. AT THIS POINT THERE WAS A SIGNIFICANT CLOUD IN FRONT OF ME AND I WAS FORCED TO MAKE A CLBING L TURN TO REMAIN VFR FOR SAFETY REASONS. I CLBED TO 4500 FT CLR OF CLOUDS IN PERFECT VFR CONDITIONS AT THIS POINT WITHOUT REALIZING IF I COULD NOT AVOID PENETRATING THE TCA WITHOUT PROPER CLRNC. I ALSO GOT IN CLOSE PROX WITH A CIVIL AVIATION AIRPLANE. I HAD THE ACFT VISUAL. HE WAS APPROX 500 FT ABOVE AND PASSED ME 1000-1500 FT N OF MY ACFT. I WAS ALREADY MONITORING SAN DIEGO DEP ON 119.6 AND WAS AWARE OF THE TFC. I CONTACTED APCH ON 119.6. THEY TRANSFERRED ME TO 124.35. I THEN RECEIVED MY IFR CLRNC AND PROCEEDED WITH MY FLT AS PLANNED WITH NO FURTHER INCIDENT. I HAD 2 PAX IN THE PLANE FOR WHOSE SAFETY I WAS RESPONSIBLE FOR. WITHOUT ALARMING MY PAX; I HAD TO AVOID A POSSIBLE EMER AND CHOSE A DESIRABLE OUTCOME FOR THE SUCCESS OF MY FLT. TO PREVENT A RECURRENCE OF A SITUATION LIKE THIS; I WILL NEVER AGAIN DEPART VFR IN MIXED OR MARGINAL CONDITIONS. OVERALL; I REALIZE MY PLANNING WAS POOR AND TO AVOID THIS HAPPENING AGAIN; 'MORE TIME ON THE GND.'