P41 Comparing WRF modeled fields to observations for the 9-10 June 2003 MCS observed during BAMEX.

Norris, Bethany, Robert Rauber, Brian Jewett, and Greg McFarquhar, University of Illinois

The 2003 Bow Echo and Mesoscale Convective Vortex Experiment (BAMEX) provides a high resolution, multi-sensor dataset that serves as an excellent basis for improving the understanding of mesoscale convective systems (MCSs) through comparisons against model simulations of the observed systems. In this work, radar observations taken during the June 9-10, 2003 MCS observed during BAMEX are quantitatively compared against numerical simulations of the same MCS performed using WRF. Comparisons are carried out using statistical distributions of variables such as radar reflectivity and Doppler velocity.

Radar observations were taken from the NOAA P-3 aircraft behind the leading convective line at various stages of evolution. Contoured Frequency by Altitude Diagrams (CFADs) of observed and modeled radar reflectivity and Doppler velocity are compared at varying times in the MCS evolution to assess the degree to which the observed and simulated MCS morphology, kinematics, and microphysics agree. In addition to examining the vertical structure of MCSs with CFADs, a new technique called Contoured Frequency by Distance Diagrams (CFDDs) is used to assess how observed and simulated microphysics and kinematics vary with distance behind the leading convective line. These analysis techniques are not critically dependent on the position and timing issues common in such observation vs. model comparisons, making them ideal for this work. The use of these techniques will ultimately permit an improved understanding of the physical processes responsible for the evolution of MCSs and allow for improvement of numerical model treatment of MCSs.