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Hail Bayannaoer of severe weather, often a serious impact to the local agricultural production in order to reduce the losses caused by hail damage, further enhanced hail suppression effectiveness, improve Bayannaoer hail forecast accuracy , the now weather map Bayannaoer hail data from 1961 to 2000, 1974-1993 2004 - 2008 713 radar data and Linhe station 08 when sounding information, using mathematical statistics, charts, analysis, similar classified methods such as hail forecast Bayannaoer research; analysis the hail Bayannao'er year, month, day variation the divided years the hail disaster level, determine the moving path of the hail, analysis of the distribution of the hail; hail short when forecasting mathematical model summarizes the the hail potential forecast indicators, hail early warning indicators; Finally, on August 6, 2007 hail application of analytical testing of hail forecast method. The main conclusions are as follows: 1. Bayannaoer hail with obvious diurnal variation concentrated in the noon to dusk (12-20), the occurrence frequency of 86.1%. Hail the duration of 5min generally do not cause disasters, more than 5min disaster, hail the longer the duration, the more serious disasters. 2. Hail days are mainly concentrated in the June-September, and increased with the age of the hail frequency was significantly increased in June to September. 1990s ,6-September, the frequency of 91.9%, the average annual number of hail days below the average of 40a, 18.7d, the hail days interannual variability. 3. Hail days disaster hail days there is a linear correlation; 1960s, 1990s hail fewer 1980s obviously more; -80 the mid-late 1970s were a severely affected years, after the 1990s, basically for two middle-disaster year or three light famine. 4. To affect the the Hetao area Bayannao'er hail cloud 10 major mobile path; zonal distribution of the high incidence of hail in the Loop, about 20 km from the Yinshan Mountains; surrounded by the Hill Hailiutu town is also hail-prone areas. Bayannaoer hail weather types are divided into the westerly flow type, the northwest airflow and southwesterly airstream type, low Groove Vortex five categories. The westerly flow hailfall forecast accuracy rate was 21.95%, hail forecast for northwest flow accuracy rate was 21.31%, the southwesterly airstream hail forecast accuracy rate of 16.33%, the low groove hail forecast accuracy rate of 27.85%, the Vortex hailfall forecast is accurate rate of 32.0%. Low Groove hail chance, the total hail Views 36.1%, the type of hail disaster probability of 80.8%. The the southwesterly airstream hail chance smallest total 5.0% of the number of hail. The northwest flow hail disaster Probability minimum of 56.0%. Parting prediction model is established, the introduction of two physical quantities of Ta, Tb, and play a good indication to better expressed at high and low levels of heating and advection strength and temperature lapse rate in the short-term forecasting of the hail. Multiple regression forecasting model, stepwise regression forecast model prediction accuracy is significantly higher than the multi indicator superposition method, omitting the least number of stepwise regression forecast model. Analysis of the the Linhe station radar data and hail data obtained four kinds of the Loop radar quantitative indicators recognition hail cloud, two qualitative indicators.
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