The past few decades have shown a marked decrease in visibility in the southeastern US. To address this concern, the Visibility Improvement State and Tribal Association of the Southeast (VISTAS) is performing an annual air quality simulation focusing on constituents, such as PM10 and PM2.5, that contribute directly to visibility impairment.

To insure that the best possible meteorological fields are used to drive the visibility simulation, a series of meteorological sensitivity tests with MM5V3.6 are performed. These tests focus on evaluating different combinations of PBL and Land-Surface schemes, because they impact directly on the near-surface meteorology crucial to accurately model atmospheric visibility.

An analysis comparing each sensitivity will be presented, including novel approaches that display color-coded station-specific statistics on the national scale. Particular attention is given to the precipitation and cloud performance, not only because these features are closely linked to the PBL and LSM schemes, but also because they drive production of sulfate aerosols, a key contributor to poor visibility.