Abstract: A computer-based system and method which incorporates long-range weather forecasts in a predictive model which quantifies historical weather impact relationships between datasets, and uses the long-range weather forecasts to predict future weather impact on managerial plans. The predictive model can use multiple regression or a neural network. In a retail application, the computer-based system and method has a weather impact predictive model based on correlations of historical weather and point-of-sale store transactions data. The weather impact model is coupled with long-range weather forecasts to adjust managerial plans for buying, distribution, financial budgeting, promotional and advertising applications. A graphical user interface provides easy assimilation of analysis for specific managerial planning applications.