Monitoring and analyzing foggy events using ground and remote sensing data Case Study April 4, 1396

This article is intended to monitor and identify the cause of the fog occurrence on the roads of the Iran that don’t have access to meteorological observation stations. For this purpose, the case study of Mashhad-Baghcheh Road, April 4, 2017, has been considered, leading to an accident of more than one hundred cars, killing one and injuring 60 people. Due to the lack of observation stations on roads, it is used the MSG satellite images during the meteorological events to monitor the phenomenon and analyzed the most important atmospheric parameters including temperature, wind, pressure, dew point temperature, low clouds and also short wave and long wave radiations on the surface level. Also, geopotential height, temperature, relative humidity and vertical velocity were measured at 850 and 700 mb levels to find the low level atmospheric circulations. The results of this study indicate that a 15 minutes after the occurrence of the phenomenon, the monitoring MSG satellite imagery is available which is a very suitable tool for very short-term forecasts. The geographical location of the area as well as blowing KATA wind has led to the fog occurrence in this region, which despite the pressure decrease, the stability of the air column has been strengthened so that vertical velocities do not exceed the high currents. Dew point deficit is also about 4 ° C at the Earth's surface. It seems that the role of satellite observations in the very short term forecasts of weather conditions, including the May incident, is denied.