Computer-implemented techniques for determining crop harvest times during a growing season based upon hybrid seed properties and weather conditions is provided. A server computer system receives data representing hybrid seed properties, including seed type, relative maturity, and weather data. The computer system creates and stores an equilibrium moisture content time series for the specific geo-location based upon weather data, which is used to determine the rate of grain dry down. The computer system calculates R6 moisture content for a specific hybrid seed based on a plurality of hybrid seed data. The computer system creates a grain dry down time series model, based on the equilibrium moisture content time series, the R6 date, the R6 moisture content, and hybrid seed properties. The computer system determines and displays a harvest time recommendation based on the grain dry down time series and the desired moisture level of the grower.
