A Study of Temporal-Spatial Distribution and Synoptic Characteristics of Severe Convective Weather in Beijing, Tianjin and Hebei
Based on the hazardous weather report, disaster telegraph data and NCEP l°× 1° reanalysis data from 175 stations in Beijing, Tianjin and Hebei from May to September during 2001-2008, the statistical analyses are used to explore the temporal-spatial distribution and synoptic characteristics of severe convective weather there. The analysis results indicate that: (1) In this period, the wind force always reaches 7-8 scales with prevailing northerly and westerly winds, the south-central and northwest of Hebei area, and Beijing and Tianjin have strong winds; Larger hails often occur in Beijing, Tianjin and the northwest and north of Hebei; Within 10-60 minutes, the precipitation easily reaches 20-25 mm, while during 130-180 minutes, the precipitation can reach 50-100 mm. (2) During 2001-2008, the winds often occur in May and June, the hails occur in June, but the short-time rainstorms occur in July and August; (3) Except for short-time rainstorms, winds and hails approach to the Taihang and Yinshan Mountains and reduce gradually from northwest to southeast. The severe convective weather has the obvious characteristics of daily variation, a majority of severe convective weathers (62％) occur in the afternoon and early evening (14:00-20:00 BT). (4) There are three main weather circulations: the cold vortex pattern in which mainly appear hails accompanied by gales or short-time rainstorms, the cold trough pattern in which mainly appear strong winds with short-time rainstorm, and the trough and subtropical anticyclone pattern which always brings short-time rainstorms. A weather conceptual model which is established through the typical case has a good significance for weather forecasting.
severe convective weathertemporal-spatial distributionconceptual model
国家科技期刊平台
NSTL
万方数据
维普
