@Gianfry If you present your question in English, you would have more luck getting more precise answers.
Some of us here are experienced with features other aren’t!
My understanding is you are wondering how come your Storm alarm doesn’t go off despite the Barometer being low?! Well, weather precipitation so called the big (L) for low pressure aren’t all the same, some are progressive and do not hold much power in them, and others are classified as deep low pressure whereby they hold load of energy. The deeper the pressure, the greater it’s impact, meaning it will move across the continent at a faster pace. These deep low pressure will trigger the Storm alarm in your watch if they approach your area fast enough. The pressure will have to drop 4hPa in 3 hours to be considered an imminent storm. Garmin watches allow you to set the time and pressure decrease to suit your need. As an example I set mine to 3hPa drop in 2.5 hours this gives me enough indication that something in the distance is changing. My experience with Suunto Core ans traverse is they are very accurate at detecting L pressure.