Impact Assessment of Different WRF Microphysics Schemes: A Case Study of a Severe Rainfall Over Egypt

Egypt faced heavy rainfall starting from 26th October 2016 which caused flooding in Upper Egypt and Red Sea Coast especially the city of Ras Gharib.In this work, Weather Research and Forecasting (WRF) model was used with one domain of 10-km resolution for three days starting from 26th October 2016 to simulate this severe rainy event in terms of precipitation, temperature, pressure and wind speed. In order to use the WRF model several schemes should be configured, one of them is the microphysics scheme. Microphysics is the process by which moisture is removed from the air, based on other thermodynamic and Kinematic fields represented within the numerical models. Sensitivity of ten microphysics schemes were tested (Kessler, Lin, WRF single moment 3 and 5 class, Eta (Ferrier), WRF single Scheme 6 Class, Goddard, Thompson, Milbrandt-Yau Double Moment and Morrison 2 moment).The output temperature and precipitation from the model were compared to the satellite data obtained from Moderate Resolution Imaging Spectroradiometer (MODIS) and Tropical Rainfall Measuring Mission (TRMM), respectively. Our analysis showed that the model has the capability to simulate the rainy event spatially and produce the cloud pattern. The results over Ras Gharib indicate that the model overestimated the precipitation for all tens schemes.The closest scheme to TRMM was Morrison 2-moment, overestimating precipitation by almost 50% while the farthest scheme was Kessler by almost 67%.The temperature was underestimated by a percentage lies between 20% - 25%, with Milbrandt-Yau 2-Moment scheme being the closest and Morrison 2-moment scheme being the farthest.