General aviation pilot reports departing FFO after reading NOTAM closing first 2500 FT of Runway 5L. Upon return several hours latter; the NOTAM is forgotten and the reporter landed in the displaced threshold.

Narrative

During preflight planning I read all NOTAMs for FFO; one of which mentioned that the threshold for Runway 05L was temporarily displaced 2;540 FT. Three hours later I returned from a VFR flight in the local area; which included a stop for dinner. By the time I returned to FFO I had forgotten about the displaced threshold NOTAM. I was cleared for the option on Runway 05L. I wanted to practice a short field landing so I aimed for the numbers and touched down within 100 FT. During the landing sequence I neglected to survey the runway carefully enough to notice the temporary displaced threshold markings. Just after touchdown I noticed the yellow markings indicating the temporary displaced threshold and instantly remembered the NOTAM. By that time I had already violated the NOTAM and landed on the temporary displaced threshold. No damage was caused to the aircraft or airfield as a result of this incident. No person was injured as a result of this incident. This incident could have been avoided had I imagined myself landing on Runway 05L as I read the NOTAM. Then I would have remembered during the landing sequence that the threshold was displaced. I could also have avoided this incident had I surveyed the runway more carefully during downwind and noticed the temporary displaced threshold markings.