Abstract:The inhomogeneity has been tested by using ratio method,based on annual precipitation series from 1951 to 1990 for four hundred stations in China. The results suggest that this method is effective to judge the inhomogeneity of annual precipitation series changes of stations and guages are major reasons which caused the inhomogeneity of annual precipitation series.

Abstract:An introduction to the diagnosis-prediction method of sudden change in Typhoon track and its test-results during June-October, 1994 has been made. The test results indicate that this method is sensible to the elements which cause track change suddenly and that its forecast for future path is uniform.

Abstract:As a practical system of personal computer,an Operational Typhoon System in South China has been developed in meteorological offices to meet the needs of the operational forecast and services. There are two versions suitable for the regional meteorological center and its sub-observatories respectively. This system consists of typhoon data managing,typhoon predicting,service distributing and demonstrating sub-systems and a technological process for typhoon forecasting. By the use of this system,the procedures of typhoon predicting will be simplified,therefore forecasters will get rid of heavy manual works.

Abstract:Based on conventional weather observation data and satellite images, 39 cases of tropical storms and severe rainfall in Guangdong Province between 1960 and, 1991 were analysed. It is found that tropical storms severe rainfall was mainly generated by meso-scale rain storm systems.A conception model and its forecasting approches of tropical storms and severe rainfall are given.In pre-operational experiments during 1994 tropical storms season, the forecast accuracy was 73%.

Abstract:Data (1970-1990) of tropical cyclones have been studied by statistical method for those with sudden changes in their moving direction and entered concerned area (15-25°N,West to 125°E). Climatic features, such as seasonal and geographical distributions, have been shown. The relations between the track sudden change and the activity of subtropical high and the terrain factors have been discussed. The results are helpfull in forecasting TC's track sudden change.

Abstract:The step method based on the least pridiction error sums of square is used to predict and fit the typhoon tracks. The results show that the ability of prediction model is strong. The method is an objective one which could predice typhoon tracks as effectively as the stepwise regression equation.

Abstract:Following correct assessment of seven objective prediction methods used in China,employing a number of statistic models such as the typical correlation,conditional combination of probability and updated method for estimating regressive coefficients,a package of composite procedures for the tropical cyclone track forecasting (including NWP product) are formulated for areas in the northwestern pacific,East China Sea and South China Sea.

Abstract:Analyses of eight tropical cyclone forecasts have been made in the operational pre-experiment in the summer of 1994. The advantages and disadvantages of these methods were given.

Abstract:The graphic system is a real-time system which has been playing an important role in T63 products output of NWP. This system provides a lot of functions,such as acquiring data,building database, quality control, data conversion, curve fitting, graphics display, artificial intervene and ete. Its special features are of easy operation,convenient to be used, plenty of products,high qualitative analysis,short running time,and providing accurate graphic products for forecasters or other users. So, it's a powerful tool for the making of weather prediction and meteorological research.

Abstract:By large-scale synthetic analysis of four northeastern banded storm weather in 1991, the main characteristics of the large-scale air current and the themodynamic environmental field are pointed out when this kind of weather happens. Meanwhile the effect of the meso-scale surface patterns and the topography upon the progress of system development also have been studied.

Abstract:The influence of easterly wave on typhoon Knotty track is discussed the result shows that there are two cases of this influence:one is that typhoon formed in the easterly wave,the other is that easterly wave moved westward and mixed with the typhoon (or tropical storm) in its southern part. These will cause typhoon track to deviate from its normal dominating air current and move northward, then pass through subtropical high, thus typhoon Knotty track appears. The reasons of forming this kind of knotty track are analysed.