Royal Rainmaking operations have helped relieve drought and have increased the water volume of dams and reservoirs, it is difficult to provide statistical and scientific analysis for conclusive proof of the effectiveness of Royal Rainmaking operation. Royal Rainmaking operations need accuracy data for planning in the next operations and monitor the water situation in the target area to prevent any damage from excess water possibly caused by the operations. The use of satellite imagery is another alternative efficient way of evaluating accurate Royal Rainmaking rainfall that occurs within the Royal Rainmaking’s target area. By using GSMaP and FY-2E (satellite) rainfall estimation models developed by IMPAC-T research group   Department of Royal Rainmaking and Agricultural Aviation  can  evaluate the effectiveness of Royal Rainmaking operations of Thailand