RWY INCURSION AT MIA; FL.

Narrative

I WAS OPERATING A FLT FROM MIA-IAH. I CALLED FOR AND RECEIVED TAXI INSTRUCTIONS FROM MIA GND TO TAXI VIA TXWY G TO RWY 9L. ONCE REACHING THE TXWY; THE CAPT MADE A R TURN AND LINED UP ON TXWY G. MIA HAD EXPERIENCED HVY RAIN THAT DAY AND JUST PRIOR TO OUR FLT LEAVING THE GATE AND CREATED SOME FLOODING AT THE ARPT AND SOME STANDING WATER ON THE TXWYS. ONCE ON TXWY Q; THE CAPT AND I COULD NOT FIND THE CTRLINE AND THE TXWY Q SIGN WAS BEHIND US. THE CAPT SAW TXWY P SIGN ON THE R AND THINKING HE WAS ON THE WRONG TXWY MADE A L TURN ONTO TXWY T THINKING IT WAS TXWY Q. AS HE STARTED THE TURN; I TOLD HIM TO GO STRAIGHT AHEAD INSTEAD OF TURNING AT WHICH HE STOPPED THE ACFT. FORTUNATELY; HE STOPPED ON TXWY T WITH THE NOSE OF THE AIRPLANE OVER THE HOLD SHORT LINE FOR RWY 12/30 BY APPROX 2 FT. I TRIED TO CONTACT GND BUT COULD NOT GET THROUGH DUE TO CONGESTION. SINCE WE COULD NOT CONTACT GND IMMEDIATELY; WE CHKED FOR DEPARTING AND ARRIVING TFC ON RWY 12/30. THERE WAS NO TFC AND WE DECIDED TO CROSS AND CONTACT GND ON THE OTHER SIDE. AFTER XING; WE WERE ABLE TO CONTACT GND AND REQUESTED TAXI INSTRUCTIONS FROM OUR POS TO RWY 9L. GND CTL SAID THEY WOULD JUST TAKE US OUT ON RWY 9R ON TXWY T.