Narrative:

Approach control repeatedly attempted to have us follow an spc (that was on a 4 mi final) for a visibility approach to 34L (we were on downwind). I informed them that the spc kept disappearing in the clouds and could not be followed visually. Approach advised us to turn a base leg and report the airport. We reported the airport in sight and were transferred to the tower (cleared for the visibility 34L). We had the ILS to 34L tuned and idented. Upon turning final we entered a very intense snow squall. We overshot the localizer and the PF made an appropriate correction to intercept the localizer. At this point the tower advised that we were not established on the inbound final. I acknowledged and informed him that we had entered an isolated snow squall and were correcting course to intercept the localizer. The controller then became quite upset and told us we would have to initiate a go around unless we reported the airport in sight. At this point the airport became visible and it was reported in sight. We landed 34L west/O further incident. The snow squall was about 4 mi from the threshold of 34L and about 3/4 mi thick. We were only in it for 10-15 seconds. This would have never happened if we had not allowed ourselves to be pressured into accepting a visibility approach.

Related reports:

Google
 

Original NASA ASRS Text

Title: CLEARED FOR VISUAL APCH IN QUESTIONABLE WX, ACFT LOST SIGHT OF RWY.

Narrative: APCH CTL REPEATEDLY ATTEMPTED TO HAVE US FOLLOW AN SPC (THAT WAS ON A 4 MI FINAL) FOR A VIS APCH TO 34L (WE WERE ON DOWNWIND). I INFORMED THEM THAT THE SPC KEPT DISAPPEARING IN THE CLOUDS AND COULD NOT BE FOLLOWED VISUALLY. APCH ADVISED US TO TURN A BASE LEG AND RPT THE ARPT. WE RPTED THE ARPT IN SIGHT AND WERE TRANSFERRED TO THE TWR (CLRED FOR THE VIS 34L). WE HAD THE ILS TO 34L TUNED AND IDENTED. UPON TURNING FINAL WE ENTERED A VERY INTENSE SNOW SQUALL. WE OVERSHOT THE LOC AND THE PF MADE AN APPROPRIATE CORRECTION TO INTERCEPT THE LOC. AT THIS POINT THE TWR ADVISED THAT WE WERE NOT ESTABLISHED ON THE INBND FINAL. I ACKNOWLEDGED AND INFORMED HIM THAT WE HAD ENTERED AN ISOLATED SNOW SQUALL AND WERE CORRECTING COURSE TO INTERCEPT THE LOC. THE CTLR THEN BECAME QUITE UPSET AND TOLD US WE WOULD HAVE TO INITIATE A GAR UNLESS WE RPTED THE ARPT IN SIGHT. AT THIS POINT THE ARPT BECAME VISIBLE AND IT WAS RPTED IN SIGHT. WE LANDED 34L W/O FURTHER INCIDENT. THE SNOW SQUALL WAS ABOUT 4 MI FROM THE THRESHOLD OF 34L AND ABOUT 3/4 MI THICK. WE WERE ONLY IN IT FOR 10-15 SECS. THIS WOULD HAVE NEVER HAPPENED IF WE HAD NOT ALLOWED OURSELVES TO BE PRESSURED INTO ACCEPTING A VIS APCH.

Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.