Thursday, 15 January 2004: 12:00 PM
Performance of National Weather Service Forecasts Versus Model Output Statistics
Model Output Statistics (MOS) have been a useful tool for human forecasters for years and have shown improving forecast performance over time. A recent advancement in the use of MOS is the application of "consensus" MOS (CMOS), which is a combination or average of MOS from two or more models. CMOS has shown additional skill over individual MOS forecasts and has performed particularly well in comparison with human forecasters in forecasting contests. An initial study comparing MOS and CMOS temperature and precipitation forecasts to those of the NWS subjective forecasts is described. MOS forecasts from the AVN, Eta, MRF, NGM models are included, with CMOS being a consensus from these four models. Data from 30 locations throughout the United States for the July 2003 - December 2003 time period are used. Performance is analyzed at various forecast periods, by region of the US, and by time/season. The results show that CMOS is competitive or superior to human forecasts at nearly all locations.