However, you will need this app if you want to customize the alerts you receive. You can specify the thresholds for alerts for individual weather quantities. For example, you are considering whether to use your bike to go to work, but don't want to get wet, so you want an alert if precipitation probability is over 60%. You might be out with a boat and want to know if some storm is coming, so you set the alert if the wind will be over 15m/s.
In such cases you get an alert to your inbox which enables you to avoid the danger of having to deal with severe weather.