Improvement in the MOS Forecast of Ceilings and Visibilities

MOS forecasts of ceiling and visibility have been available for a number of years. The current set of regression equations have been deri ved from a mix of 6LPE and LFM1 model output data and run from LFMII input data. TDL has now developed a set of equations based on a mix of LFM1 and I1 model output data and designed to run from LFMII input data. In addition, the method of selecting the "best category" from the probability forecasts of six categories has been redesigned to improve the skill of the forecasts of the lower 3 categories (<1000', <3 miles) and to increase their bias towards 1.0.