Evaluation of Weather Research and Forecasting (WRF) Model Simulations over Middle East

Abstract

The Weather Research and Forecasting (WRF) model is an atmospheric simulation system designed for both research and operational applications. This worldwide used model requires a sophisticated modeling experience and computing skills. In this study, WRF model was used to predict many atmospheric parameters based on the initial conditions extracted from the datasets of NOMADS (NOAA National Operational Model Archive & Distribution System). The study area is basically the region surrounded by the longitudes 15o-75o E and latitudes 10.5o-45o N which typically includes the Middle East region. The model was installed on Linux platform with a grid size of 10 km in the zonal and meridional directions. A low pressure trough was tracked in its movement from west to east via the Middle East during the period from 1 to 7 January 2010 as a case study of the WRF model. MATLAB and NCL (NCAR Command Language) were used to display the model output. To evaluate the forecasted parameters and patterns, some comparisons were made between the predicted and actual weather charts. The WRF model could give agreeable simulations to the weather conditions in the case study. Wind speeds and directions in the prognostic and actual charts of 700 hPa were adequate especially for the first 4 days. A further comparison between the results of WRF with the results of another model “Shallow Water Equations Model” for velocity and geopotential height shows that WRF gives better simulation. The predicted values of geopotential heights in WRF are somewhat overestimate the actual geopotential heights which may be attributed to the differences in the data sources and data analysis methods of the two data systems, NOMADS and ECMWF.