长治小麦干热风预报研究

对长治市主要麦区的5个代表县(市)1977-2006年每年6月1-20日逐日最高气温、14:00相对湿度和风速资料进行统计,发现在分析期内当地曾出现过30次小麦干热风天气过程。通过对这30次干热风过程中的500hPa环流形势、850hPa温度与湿度场的配置及地面气压场特征进行深入分析,结果表明:造成干热风天气过程的500hPa环流形势主要有两槽一脊、西北气流、一槽一脊和东亚大槽四种标志型天气模型;地面气压场中,河套地区处于宽广的暖低压控制;850hPa天气图上,105°E-117°E、32°N-40°N范围存在明显的干暖区,且轻重干热风天气过程取决于850hPa干暖区的强度。应用欧洲中心及中国T213、T639数值预报产品与标志型天气模型及850hPa干暖区指标相结合,成功地对2009年6月1-3日出现的干热风天气过程进行了试报,获得了较好的预报服务效果。

Prediction of Wheat Dry-hot Wind in Changzhi City

Based on the daily highest temperature,the relative humidity at 14∶00 and wind speed during 1st to 20th in June from 1977 to 2006 from 5 observation stations in Changzhi city,the circulation situation in height of 500hPa,the configuration of temperature and humidity in height of 850hPa and the characteristic of ground pressure field of the 30 dry-hot winds were analyzed.The results showed that the 500hPa circumfluence situation,which resulted in dry-hot wind weather process,included four weather models： two groove-one ridge,northwest airflow,one groove-one ridge,and East Asian large groove.Hetao region was controlled by the huge warm-lower system in the ground pressure field.850hPa weather map,the dry warm area were in the range of 105 °E to 117°E and 32°N to 40°N,and its intensity affected dry-hot wind intensity.The dry-hot wind weather process in June 1-3,2009 was predicated successfully by using the numerical forecast products of Europe center and China＇s T213,T639 and the landmark weather model method and 850hPa dry warm area index.