TXWY EXCURSION. TXWY CONDITION SNOW.

Narrative

I WAS THE CAPT ON AIRLINES FLT FROM LGA TO YUL ON A B- 727. YUL ARPT WAS CLOSED AFTER WE ARRIVED IN AREA WHILE RWY 6L WAS CLRED OF SNOW. AFTER A SHORT DELAY; WE WERE CLRED FOR THE APCH AND LNDG ON RWY 6L. I CLRED THE RWY ON TXWY B-3; TURNING WBOUND ON TXWY B. THE BRAKING ACTION WAS FAIR TO POOR ON THE RWY; BUT THE TXWYS WERE COVERED WITH SNOW WITH POOR BRAKING. THE TXWYS AND TXWY SIGNS WERE NOT CLRLY VISIBLE; BUT RED OR ORANGE FLAGS WERE USED TO MARK EDGES. I TAXIED W ON TXWY B AND GND CTL TOLD US TO CROSS RWY 10-28 AND CONTINUE TO TERMINAL. I STOPPED THE ACFT AT WHAT APPEARED TO BE THE INTXN OF TXWYS B AND B-2. I HAD THE FO VERIFY WITH GND THAT THIS WAS THE TXWY WHERE WE HAD TO MAKE A L TURN AND CROSS RWY 10-28. GND CTL SAID; 'NO;' NOT TO TURN L BUT TO CONTINUE R. SHORTLY THEREAFTER; WE WERE STUCK IN 3 FT OF SNOW. THE PAX (108) AND CREW WERE TAKEN TO THE TERMINAL BY BUS AFTER EXITING BY USE OF THE REAR STAIRS. THE ACFT WAS TOWED TO THE TERMINAL BY MAINT. THERE WERE NO PAX OR CREW INJURIES NOR WAS THERE ANY ACFT DAMAGE. THE POOR VISIBILITY AND SNOW- COVERED TXWYS AND MARKINGS CONTRIBUTED TO OUR GETTING STUCK. GND CTL HAD GND RADAR BUT DID NOT GIVE US THE CORRECT INSTRUCTIONS WHEN WE ASKED FOR VERIFICATION.