E120 CREW WAS GIVEN A VISUAL APCH TO SAN AND ALTHOUGH THEY HAD THE RWY IN SIGHT; THE TWR RPTED RVR 6000 FT WHILE THEY WERE ON SHORT FINAL.

Narrative

BEFORE STARTING THE APCH AT SAN WE RECEIVED WX 3 MI VISIBILITY AND 100 FT SCATTERED. APCH BROUGHT US IN LONGER THAN USUAL AND CLOSER TO THE ARPT. I TOLD THEM I HAD THE ARPT IN SIGHT; ALTHOUGH IT WAS PARTIALLY OBSCURED BY WHAT I THOUGHT WERE LOW CLOUDS FROM THE WX RPT. DUE TO AN ACFT ON FINAL TO FOLLOW US AND BECAUSE WE WERE LOWER THAN USUAL FOR AN APCH AT THIS ARPT; I TURNED FINAL TOO SOON AND FOUND MYSELF SOMEWHAT HIGH ON THE APCH. I ATTEMPTED TO CORRECT THIS BY DSNDING AGGRESSIVELY. ABOUT THE TIME WE TURNED ON FINAL; THE TWR RPTED LNDG RVR AT 6000 FT. IT NEVER OCCURRED TO ME THAT MEANT WE WERE NO LONGER LEGAL FOR A VISUAL APCH. I WAS BUSY TRYING TO GET DOWN AND STABILIZE THE APCH PATH. THIS RESULTED IN NUMEROUS GPWS 'SINK RATE' WARNINGS; WHICH SUBSIDED ABOUT 100 FT ABOVE THE RWY. IT STILL RESULTED IN A FIRM LNDG AND THEN WE ROLLED INTO SOME VERY DENSE FOG AND HAD TO SLOWLY PICK OUR WAY OFF THE RWY ONTO THE TXWY. IT WOULD HAVE BEEN HELPFUL TO GET AN RVR READING AS SOON AS WE TALKED TO TWR OR FROM SOCAL APCH BEFORE THEY GAVE US CLRNC FOR THE VISUAL.