This proposal addresses the needs of the Lake Michigan Air Directors Consortium (LADCO), which conducts State Implementation Plan (SIP) air quality assessment modeling for its member states: Illinois, Indiana, Michigan, Ohio, and Wisconsin. SIP modeling is required under the Clean Air Act to demonstrate strategies to mitigate nonattainment of the National Ambient Air Quality Standards associated with ozone exceedances along the Lake Michigan shoreline. We will support LADCO through development, verification, and delivery of a satellite-constrained meteorological modeling platform to conduct air quality assessment modeling for ozone in the Lake Michigan region. Meteorological modeling for this region is challenging due to the influence of mesoscale lake breeze circulations on the transport and chemistry along the Lake Michigan shoreline. The modeling platform will be based on the Weather Research and Forecasting (WRF) model and will include regional nests covering the LADCO states and Lake Michigan with 4- and 1.3-km resolution, respectively. These high-resolution domains will be nested within a continental scale 12-km resolution domain that is similar to that used by the Environmental Protection Agency. Tracking of the observed synoptic evolution within regional downscaling runs will be accomplished through 3-dimensional and surface analysis nudging. Sensitivity experiments will be conducted to determine the optimal configuration for the LADCO meteorological modeling platform. Airborne and ground based in situ and remote sensing observations collected during the 2017 Lake Michigan Ozone Experiment (LMOS 2017) will be used to evaluate these sensitivity experiments. NASA Soil Moisture Active Passive (SMAP) soil moisture and MODIS/VIIRS green vegetation fraction retrievals will be assimilated into the NASA Short-term Prediction Research and Transition Center (SPoRT) Land Information System (SPoRTLIS), with soil and land surface output used to initialize and nudge the WRF model predictions. High-resolution (1.8-km) sea surface temperature (SST) analyses from the NOAA Great Lakes Environmental Research Laboratory (GLERL) will be combined with SST retrievals derived from MODIS and VIIRS observations to provide boundary conditions for the WRF surface temperature predictions. Cloud optical thickness (COT), cloud top pressure, and transmissivity retrievals from GOES, including the Advanced Baseline Imager onboard GOES-16 will be used to post-process the WRF output and apply regime-dependent bias corrections to the predicted COT to improve photolysis rate calculations. High-resolution VIIRS Day Night Band reflectances will be delivered to LADCO to provide spatial surrogates for downscaling anthropogenic emissions to the 4- and 1.3-km resolution nests. At the end of the project, we will deliver a well-tested modeling platform to LADCO that will leverage NASA satellite observations and land surface data assimilation capabilities to improve their ability to address the requirements of air quality assessment modeling along the Lake Michigan Shoreline. In addition, because the challenges of simulating the lake breeze along the Lake Michigan shoreline are similar to those associated with simulating bay and sea breeze circulations in other regions, we anticipate that the LADCO modeling platform developed during this project will also have utility for ozone forecasting and assessment activities in other parts of the country where these transport regimes occur.