Narrative:

While on the localizer 27 approach into san diego; the tower told us that we would break out right at minimums. Concerned about getting down; I left reebo at 800 to 1;000 FPM descent to the derived decision altitude (dda). The base of the layer was ragged and just prior to the dda I saw the PAPI appear; disappear; and reappear. At dda; I had the PAPI and immediately noticed an area of lower visibility north of the runway. I called 'landing'. Concerned that the area of lower visibility may move over the runway; I allowed the aircraft to descend at the higher rate of descent than I had started from the FAF. With it being daylight and the terrain and obstacles insight; I was lulled into focusing on the area of low visibility. This was apparent when the first officer correctly called 'airspeed' when I allowed the airspeed to drop more than five knots below target. I corrected; but was still focused on the area of low visibility. Then we received the alert 'terrain too low'. That got my attention and I corrected immediately. At the same moment of the alert; I saw the PAPI had turned four red. I brought the aircraft up to the PAPI glide path and the rest of the approach and landing was uneventful. The area of lower visibility stayed to the north of the runway and never became a factor. The first thing I did wrong was forgetting my first priority to fly the aircraft. The second thing I did wrong was [that I was] too lulled into a sense of security by having the terrain in sight. The third thing I did wrong was to focus on the area of low visibility which caused me to lose focus on the first two priorities. I allowed myself to be distracted. Ironically this area of focus; the low visibility never became a factor; yet it brought other more serious factors into play. Fly the airplane!

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Original NASA ASRS Text

Title: A B737-300 flight crew reported receiving a GPWS alert for terrain on approach to SAN.

Narrative: While on the LOC 27 Approach into San Diego; the Tower told us that we would break out right at minimums. Concerned about getting down; I left REEBO at 800 to 1;000 FPM descent to the Derived Decision Altitude (DDA). The base of the layer was ragged and just prior to the DDA I saw the PAPI appear; disappear; and reappear. At DDA; I had the PAPI and immediately noticed an area of lower visibility north of the runway. I called 'landing'. Concerned that the area of lower visibility may move over the runway; I allowed the aircraft to descend at the higher rate of descent than I had started from the FAF. With it being daylight and the terrain and obstacles insight; I was lulled into focusing on the area of low visibility. This was apparent when the First Officer correctly called 'airspeed' when I allowed the airspeed to drop more than five knots below target. I corrected; but was still focused on the area of low visibility. Then we received the alert 'Terrain Too Low'. That got my attention and I corrected immediately. At the same moment of the alert; I saw the PAPI had turned four red. I brought the aircraft up to the PAPI glide path and the rest of the approach and landing was uneventful. The area of lower visibility stayed to the north of the runway and never became a factor. The first thing I did wrong was forgetting my first priority to fly the aircraft. The second thing I did wrong was [that I was] too lulled into a sense of security by having the terrain in sight. The third thing I did wrong was to focus on the area of low visibility which caused me to lose focus on the first two priorities. I allowed myself to be distracted. Ironically this area of focus; the low visibility never became a factor; yet it brought other more serious factors into play. Fly the airplane!

Data retrieved from NASA's ASRS site as of July 2013 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.