Abstract
As a manifestation of low-altitude wind shear, a downburst is a localized, strong downdraft that can lead to disastrous wind on the ground surface. For effective pre-warning and forecasting of downbursts, it is particularly critical to understand relevant weather features that occur before and during a downburst process. It is important to identify the macroscopic features associated with the downburst weather process before considering fine-scale observations because this would greatly increase the accuracy and timeliness of forecasts. Therefore, we applied the wind-vector potential-temperature energy analysis (WPEA) method and CSU-CHILL X-band dual-polarization radar to explore the features of the downburst process. Here it was found that prior to the occurrence of the downburst of interest, the specific areas that should be monitored in future events could be determined by studying the atmospherically unstable areas using the WPEA method. Combining the WPEA method with dual-polarization radar observations, we can better distinguish the phase distribution of the hydrometeor in the process and greatly enhance the judgment of the possibility of the downburst. From exploration of the microphysical features of the downburst, we further found that ‘Zdr (differential reflectivity) column’ can be regarded as an important early warning indicator of the location of the downburst. Finally, a schematic of the formation process of the downburst according to the analyses was produced.
Highlights
A downburst refers to a downward-moving middle-air current that on reaching the surface can generate disastrous divergent or linear ground-level horizontal wind speeds >17.9 m/s [1].After convective storms develop into a mature stage, cold downdrafts within the thunderstorm clouds can become sufficiently strong to form outflows and squall lines on reaching the ground
In 1986, using polarization information provided by dual-polarization weather radars, Fujita and co-workers [25] studied the types of precipitation particles and they analyzed the microphysical change characteristics of thunderstorm clouds before the occurrence of a downburst
This study study conducted conducted in-depth in-depth analysis analysis of of the the weather weather process process of of aa typical typical downburst downburst
Summary
A downburst refers to a downward-moving middle-air current that on reaching the surface can generate disastrous divergent or linear ground-level horizontal wind speeds >17.9 m/s [1]. In 1986, using polarization information provided by dual-polarization weather radars, Fujita and co-workers [25] studied the types of precipitation particles and they analyzed the microphysical change characteristics of thunderstorm clouds before the occurrence of a downburst. Using dual-polarization radar variables, Doviak and Zrnic [22] conducted detailed analysis and calculation both to determine the capability of the radars to identify various hydrometeors and to establish the value ranges of the various variables Based on those results, Straka and Zrnic [27] further proposed the use of fuzzy logic algorithms to identify the phases of precipitation particles. Based on the Hydrometeor Classification Algorithm function, Mahale et al [29] used the KOUN dual-polarization radar in Oklahoma (USA) to study a downburst event, analyzing the detail of the microphysical evolution characteristics of the process and obtaining a corresponding conceptual model.
Sign-in/Register to view highlights & summary 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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
