Diagnosing Convective Instability fromGOES-8Radiances

Statistical algorithms are developed to diagnose the vertical change in equivalent potential temperature ( e ) between 920 and 620 hPa from GOES-8 radiance data. The models are prepared using a training dataset of radiosonde releases from 10 United States cities. Simulated GOES-8 channel brightness temperatures are calculated from these soundings. The training data are stratified into several subsets (depending on time and location). Models trained only on 0000 or 1200 UTC data explain approximately 7% more of the variance in observed e than those trained on both 0000 and 1200 UTC. Values of R 2 from models using training data from only one are superior to those trained on multiple stations. Inclusion of the imager channels adds little information to the algorithms.