The Forecast System of Cloudy - rainy Weather for Several Days during the Reap Period of Wheat in Henan Province

With weather chart during the reap period of wheat from 1961 to 1995, the synoptic situation of cloudy - rainy days has been classified. After similar analyses on synoptic situation with similar forecast, the synoptic type of cloudy - rainy weather for several days has been gotten, also we can judge the whether or not the appearance of according to the calculative result of grey forecast model.