Abstract
Objectives: To discuss and introduce the reality of the first tornado in Nepal: its development process, position, shape and size, and power strength. Methods: We analysed data of satellite images from 30 to 31 March 2019, which was downloaded from EOSDIS NASA—a world weather archive system of daily weather and climate observations that is freely available over the Internet. Various true colour images of Terra Modis, with corrected reflectance, were observed to detect the cloud cell thickness by the use of cloud density with brightness temperature images that provide the colour difference both in day and nights, which can be observed very easily. Findings: From the analysis of test image samples, the black–white background of cloud mask system of brightness temperature that clearly distinguished the cyclonic structure of the tornado with its shape, size, and position including its tracks in the atmosphere was found, which was also compared with the image from European satellite systems to conform its real power strength. We found large instability of the atmospheric condition with large heating system of surface temperature and solar radiation with the two systems of air mass (Westerly and S-Easterly) transports combined each other and produced the environment for the formation of more powerful tornado on 31 March 2019 in Nepal. Many atmospheric cyclonic activities in different climatic conditions and their impacts were observed in the past; however, recent cyclone-induced hazards are assumed to be increasing because of regional weather and climate change in south Asian countries. Even a single weather event, first tornado in Nepal on 31 March in the south-eastern part of Nepal, made large-scale damages of people and settlements within a few hours. Application: Many freely available Internet systems for observing extreme event of weather and climatic conditions can be used for daily forecasting system in order to ensure safety from all possible disasters. Keywords: Weather-change, Tornado, Impacts, Sat-image, Forecasting, South Asia
Highlights
Tornadoes are formed when a large convection of atmospheric disturbance exists due to large unstable condition of atmosphere with respect to heat, temperature, low pressure, and high wind speed
The summer monsoon season exhibits large temporal and spatial variations with precipitation patterns governed by both monsoon circulation dynamics and orography.[3]
The size and speed of a tornado event generally vary with the heating system from the land, latent heat released within the atmosphere, altitude of local geography, and seasons and land or surface features
Summary
Tornadoes are formed when a large convection of atmospheric disturbance exists due to large unstable condition of atmosphere with respect to heat, temperature, low pressure, and high wind speed. Tornadoes are formed when moist vapour mass transport to atmosphere, where the large mass of vapour condense due to high temperature lapse rate on its ascent or transport path In this situation, a vast amount of heat is released, which cause temperature inversion (warming) in higher level atmospheric layer and heated up. With the warming of the atmospheric layer due to condensation and expansion of moist air with low pressure systems in the upper level of atmosphere, air mass system gains high speed motion in circulatory paths. March is considered generally last of winter and beginning of the pre-monsoon periods in Nepal
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
