A multi-scale WRF-ARW (v3.5.1) simulation is performed with hopes to forecast the CI in northwestern Kansas. On a 12 km outer domain, synoptic and mesoscale observations are assimilated every three hours to better analyze the pre-storm environment. The inner convection permitting domain assimilates radar observations (reflectivity and radial velocity) every five minutes and conventional observations every 30 minutes. Results from a June, 2013 case study are positive and have shown the impact of DA on nocturnal CI forecasts. While a control forecast with no DA had little to no CI in the area of interest, ensemble forecasts with DA showed strong agreement in CI. The addition of conventional observation assimilation on the inner domain improved the analysis of the surface outflow and associated cold pool of a weak MCS in southwestern Kansas of which the convection formed off of.
Since CI is known to be sensitive to both planetary boundary layer (Kain et al. 2008) and microphysics parameterization schemes (Burghardt et al. 2014), correct tuning of DA parameters such as localization for different scales and observation types are important in order to improve forecasts. Additionally, since nocturnal CI is likely influenced by gravity waves and other small-scale processes, such as bores, outflows, and solitary waves, smaller grid spacing may be needed to accurately represent the physics processes that produce CI. Initial results to test the impact of these different model configurations and parameterizations on CI forecasting will be presented for cases from three of the CI intensive observation periods (IOPs) during PECAN. Additionally, results will be presented that show the impact of assimilating new observations recorded during the project, such as mobile soundings and both fixed and mobile profiling units.