A study was conducted to predict the future regime of temperature and rainfall for Ghana over 50 years. The basis for the prediction lies in simulations of relevant Global Climate Models (GCM). However, forecasts on a generally regional scale lack important historical characteristics, or behavior, of rainfall and temperature on a smaller or local scale. More precise forecasts are required, and modifications are made using a unique, in-house rainfall prediction model that has been developed with the Vrije University Amsterdam and Dutch meteorological organization KNMI. This mathematical predictor improves on GCM model predictions of rainfall and temperature by also incorporating the statistical properties of current-day rainfall and temperature data series in the specific target area. Prediction results are therefore more realistic.