Cumulus software used with the weather station attempts to predict a weather forecast for the coming 12 hours.
It uses an algorithm based on the pressure and trend, wind speed, the month, and where we are.
The initial formula was developed in the early 1900s and was based on years of observations and testing and proved to be around 91% accurate. It is said to have been extensively tested by NATO in the most extreme weather conditions. It has been demonstrated that the most accurate forecasts are based on readings taken at 9am; however, it apparently continues to give reliable results throughout the day.