亚帆赛期间一次弱冷空气补充致海面强风及预报失败的原因分析

Reflection on a Forecast Failure of Coastal High Wind induced by Weak Cold Air Supplement during the 14th Asian Sailing Competition

利用常规天气资料、2000～2010年华南部分站点的海平面气压资料,分析了第14届亚洲帆船锦标赛期间(2010年3月21～29日)一次弱冷空气补充影响过程。结果表明,该次过程预报失误,主要是由于第2股弱冷空气到达造成的升压幅度达不到第1股较强冷空气减弱造成的降压幅度,再加上太阳辐射及日月引起的大气潮影响形成的海平面气压日变化,使得28日华南24 h和逐3 h变压均为负变压,导致用常规方法很难判断出该次弱冷空气补充过程。而通过相对气候平均3 h变压的距平变化可以分析出该次东路弱冷空气过程。在实际预报业务中,除了要重视实时业务资料的分析外,还必须了解本站气象要素的日变化历史气候规律。

Conventional observation data, especially the sea level pressure data in South China are used to analyze the forecast failure of a weak cold air supplement during the 14th Asian Sailing Contest （21-29 March, 2010）. Results show that the supplement of the weak cold air was neglected because the pressure rise by the second cold air was still lower than the pres- sure drop when the first cold air mass moved out, and what more, the solar radiation and the lunar forcing atmospheric tide al- so contributed to the diurnal change of sea level pressure. However, relative climate averaged 3-hour pressure departure can re- veal the east-path weak cold air movement. In the operational forecast practices, besides the real time data analysis, under- standing the climatic characteristics of the local weather elements are also very important.