Only monitoring the weather data ( Temperature, Humidity,Pressure and Altitude ) is not so interesting. So my friend  3KU_Delta thought to implement the forecast algorithm in to the Software.

The only algorithm that fulfill our purpose is the Zambretti algorithm. The Zambretti Forecaster is a weather forecasting tool in the form of a circular slide rule that was introduced by the company Negretti and Zambra in 1920. A more detailed description about the functionality of the Zambretti Forecaster and how to put it into code can be found here. The input parameters of the algorithm are season, sea-level pressure, barometric tendency, hemisphere and wind direction. The algorithm is empirical and created for the northern hemisphere and more specifically Great Britain.

The algorithm conclude, that wind direction has little effect to the final result, which is a good thing because wind direction sensor is still not used . We get the temperature, humidity and station pressure from the sensor, but the relative pressure should be derived from the station pressure. The output of the Zambretti Forecaster is one of 26 different weather conditions. 

Now you can see the updated code on GitHub