广州市11月强冷空气特征概述及典型个例分析

强冷空气过程是广州市11月的高影响天气类型之一.通过分析广州地区5个站1961～2009年11月的日平均气温、日最高气温、日最低气温及日雨量等数据,以及NCEP 2°×2°再分析资料.并根据广东省气象局的灾害性天气标准,发现1961～ 2009年影响广州的强冷空气过程共有8次,没有寒潮过程出现.从24h的降温幅度看,1...

Reviews on the Strong Cold air Events in November of Guangzhou and a Typical Case Study

Strong cold air is one of the high impact weathers in Guangzhou in November.This paper analyzes the observational data of daily mean temperature,maximum temperature,minimum temperature and daily rainfall amount from 5 stations of Guangzhou in November during 1961 to 2009,together with the NCEP reanalysis data(2×2 deg).Results show that no cold wave but 8 strong cold air events are found during this period according to the cold wave criteria of Guangdong.Among them,the one arriving at Guangzhou on November 27,1987 is the strongest.In this case,cold air outburst southward steered by meridionally turning of transversal trough at 500 hPa,with the tropical cyclone NINA approaching coast and sustaining for 24 hours,which supply favorable moisture and convergence for the precipitation.Significant gradient wind between tropical systems and the cold air mass accelerated the southward cold air.Development of the low trough in western China causing a warming up in Guangzhou before the cold air outbreak,also cause a relatively significant drop in temperature.