NUMERICAL RAINFALL PREDICTION PERFORMANCE OF IMPROVED HLAFS DURING THE CATASTROPHIC FLOOD OF 1998

The rainfall prediction products of improved HLAFS were verified for the catastrophic flood period of 1998. The results show that this model performed better in Songhuajiang-Nenjiang River Valley for torrential rain forecast, better in the middle and lower reaches of the Yangtze River and worse in the Three-Gorges area for the moderate and heavy rain forecasts. Usually, The predicted rainfall intensity is weaker than the observed for the main rainfall processes. In about half causes, the predicted rainfall area is to the north of the real while the predicted axis is consistent with the real. The improved HLAFS performs better for light rainfall prediction and shows improvement for moderate and torrential rainfall. However, the overall predicted rainfall area is too large and the accuracy of heavy and torrential rain prediction needs further improving. For the rainfall amount prediction around the Three Gorges area, in about half causes, the model performs well with less predicted amount for heavy rain and larger one for small rain.