In German sugar beet growing areas Cerospora beticola is the most important pathogen. In each year C. beticola epidemics occur with increased severities in warm and humid areas or on irrigated fields. They result in considerable yield reductions and negatively affected quality parameters. For the steering of monitoring activities a forecasting model for the first regional occurrence (CERCBET 1 which is an adaption of the CERCOPRI model developed at Piacenza University) is used. The satisfying results of CERCBET 1 was encouraging the elaboration of a model which predicts the further development of early Cercospora epidemics and helps in the timing of fungicide applications. The newly developed model (CERCBET 3) forecasts disease incidence (DI) curves on a plot-specific scale. CERCBET 3 was tested in 2001, 2002 and 2003. Results were very promising. In 72%, 82% resp. 85% of the cases CERCBET 3 correctly forecasted the date when an action threshold based on DI values was overridden. However the model needs improvement. It is intended to include the influences of irrigation and cultivar susceptibility into CERCBET 3. In addition a module to reflect fungicide efficacy is under development.