A study of short-duration convective rainfall leads to Flashflood event in Kan and Sijan Regions (Case Study: July 19, 2015)

Volume 1, Issue 2 - Serial Number 2
Summer 2018
Pages 163-176

Document Type : Original Article

Authors

Assistance Prof. of Atmospheric Science and Meteorological Research (ASMERC), Tehran, Iran

Abstract
In theflood19July 2015, short-duration convective rainfall leads to flashflood in an area of about 300 km2 are falling in the short termand due to intense rainfall in a short time, being a small basin area ,low concentration time and man-made factors destructive terrible flood occurred. In this paper, using WRF model and weather patterns, the devastating floods, from the meteorological perspective is studied.The results of the simulated instability indicators, consider to be suitable for the structure of the atmosphere and the lack of preventive factors of convection has been to create a severe instability and rainfall amounts resulting from the model outputsat the time of the occurrence floodis also well simulated by the model. Large-scale atmospheric patterns of 19 July, the existence of the thermal low pressure center on the South and southeast and the gradual expansion of the thermal low pressure to the central areas of the country and the establishment of the high pressure plumes on the Caspian coast with intense pressure gradient on the central Alborz that shows with the levels trough of the middle and upper atmosphere associated and favorable conditions for the occurrence of extreme precipitation has provided.

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