THE PLANT LOST POWER DUE TO THUNDERSTORM / LIGHTNING MOVING THROUGH AREA. EE WENT TO THE SCRUBBER DECK TO OPEN DRAINAGE FLAPS. HE THEN TURNED TO WALK DOWN STAIRS WHEN A SUDDEN UNEXPECTED GUST OF WIND BLEW HIM OFF THE PLATFORM. HE FELL APPROXIMATELY 25 FEET TO GROUND - PLATFORM DOES HAVE PROPER RAIL GUARDING.