THE PLT RPRTD THAT WHILE TAKING OFF (NORTH), THE ACFT ROLLED ABOUT 400 TO 500 FT, THEN ENCOUNTERED A GUST OF WIND & VEERED LEFT. SUBSEQUENTLY, IT COLLIDED WITH AN UNOCCUPIED ACFT THAT WAS PARKED ABOUT 50 FT FROM THE EDGE OF THE RWY. AT THAT TIME, A THUNDERSTORM CELL WAS LOCATED NEARBY. THE PLT ESTIMATED THE WIND WAS FROM 260 DEG A 15 GUSTING 18 KTS.