首页 | 本学科首页   官方微博 | 高级检索  
     检索      


A Mediterranean derecho: Catalonia (Spain), 17th August 2003
Authors:J Manuel Lpez
Institution:aInstituto Nacional de Meteorología, Centro Meteorológico Territorial en Catalunya C/Arquitecte Sert no. 1, 08005 Barcelona, Spain
Abstract:At approximately 6:10 UTC in the morning of 17th August 2003, a squall line developed over south Catalonia (the northeast region of Spain). During the next 9 h, the squall moved rapidly northeast and crossed Catalonia and the French regions of Languedoc–Roussillon and Province, damaging and uprooting hundreds of trees and blocking trains in the region. Wind gusts reached were recoded up to 52 m/s with evidence of F2 intensity damage. This case study shows the characteristics of a derecho (widespread convectively induced windstorm).Radar observations of the evolving squall line show signatures often correlated with damaging surface winds, including:
a. Bow echoes,
b. Rear inflow notches,
c. Rear inflow jets,
d. Medium altitude radial convergence,
e. Narrow gradient of very marked reflectivity,
f. Development of isolated cells ahead of the convective line,
g. A band of convection off the northern end of the line known as a “warm advection wing”.
When examining the different surface observations, satellite, radar imagery and cloud-to-ground lightning data, this case shows many similarities to those investigated in the United States. The derecho is a hybrid case, but has many characteristics of warm season derechoes. This emanates from a mesoscale convective complex (MCC) moving along a quasi-stationary, low-level thermal boundary in an environment characterized by high potential instability and relatively strong mid-tropospheric winds.
Keywords:Severe weather  Derecho  Bow echo  Windstorm
本文献已被 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号