Anatomy of a Summertime Convective Event over the Arabian Region

We use the WRF Model with 1-km horizontal grid spacing and test three PBL parameterizations: the Mellor-Yamada-Nakanishi-Niino (MYNN) scheme; the Asymmetrical Convective Model, version 2, (ACM2) scheme; and the quasi-normal scale-elimination (QNSE) scheme. Convection initiates near the Al Hajar Moun-tains of northern Oman at around 1100 local time (LT; 0700 UTC) and propagates northwestward.

A nonorographic con-vective band along the west coast of the United Arab Emirates (UAE) develops after 1500 LT as a result of the convergence of cold pools with the sea breeze from the Arabian Gulf. The model simulation employing the QNSE scheme simulates the convection initiation and propagation well. Although the MYNN and ACM2 simulations show convective ini-tiation near the Al Hajar Mountains, they fail to simulate the development of the convective band along the UAE west coast.