Abstract: A two-dimensional,time-dependent numerical model has been used to study the possibility and the micro-physical Processes of a warrn fog dissipation in a limited area by seeding with small salt particles. The effects of the salt particle size the amount of salt seeded in an area of 1m2,the thickness of the fog and the liquid water content in the fog on the efficiency of the fog dissipation have been investigated.It has been indicated by the results that it is possible to increase the visibility in fogs by salt-seeding in a limited area. The larger the salt particle size and the more the amount of salt seeded,the more efficient the fog dissipation seems to be,but the cost and the pollution on environment are also increased. Finally,the possibility of using large water drops in warm fog dissipation has been discussed.