The Snow Day Predictor is updated on a daily basis. The algorithm is designed to learn on a daily basis and adjust its predictions as needed. It uses weather data from the National Weather Service, temperature readings from the National Oceanic and Atmospheric Administration, and snowfall measurements from the National Snow and Ice Data Center. The Snow Day Calculator also uses a variety of machine learning techniques to analyze historical weather data and make predictions. This data is updated daily, with new data being incorporated into the algorithm each day. With this information, the Snow Day Predictor can accurately predict snow days up to five days in advance.