B190 CREW DSNDED BELOW ASSIGNED ALT WHILE LOOKING FOR RWY.

Narrative

IT WAS THE FIRST LEG OF THE THIRD DAY OF A 4 DAY TRIP. HOWEVER IT WAS THE CAPT'S LAST LEG BEFORE A FEW SCHEDULED DAYS OFF. THE CAPT EXPRESSED CONCERN ABOUT MAKING IT BACK TO OUR HUB IN TIME FOR HER TO MAKE A CONNECTING FLT TO COMMUTE HOME; AND I LET THIS PRESSURE RUSH ME. WHILE ON A VECTOR TO SET US UP FOR THE BASE OF A VISUAL APCH; WE WERE INSTRUCTED TO DSND TO 2800 FT. I WAS THE PF. A CONVERSATION ENSUED BTWN THE CAPT AND THE CTLR; WHO ASKED IF WE COULD ACCEPT A SHORTER; CLOSER PARALLEL RWY DUE TO TFC. AFTER CONFERRING WITH ME; THE CAPT ACCEPTED THE SHORTER RWY TO SAVE TIME. AT THIS POINT WE WERE INFORMED WE WERE #1 FOR THE SHORT RWY; AND TO RPT THE FIELD IN SIGHT. THE PRESSURE WAS ON; SINCE THERE WAS ANOTHER ACFT THAT WAS ALSO FOLLOWING US. THE ARPT LIGHTS; HOWEVER; WERE DIFFICULT TO SEE THAT NIGHT DUE TO SNOW BANKS ON THE SIDE OF THE RWY. IN THE CAPT'S AND MY OVEREMPHASIS WITH FINDING THE ARPT SO WE COULD RPT IT; I INADVERTENTLY LET THE AIRPLANE DSND TO 2400 FT (WE HAVE NO AUTOPLT). I NOTICED WHEN THE ALT ALERTER INDICATED A DEV; AND I IMMEDIATELY BEGAN CORRECTING. APCH ISSUED A LOW ALT WARNING A SECOND OR TWO LATER. THIS INCIDENT WAS ESPECIALLY DISTURBING SINCE I'VE NEVER COME CLOSE TO BUSTING AN ALT. IN THE FUTURE; I PLAN TO AVOID PRESSURING MYSELF INTO RUSHING; AND PAYING EVEN MORE ATTN TO MY ALT IN THE TERMINAL ENVIRONMENT. ALSO; AS A PNF; I PLAN TO PAY MORE ATTN TO FLT PATH AND AIRSPD.