A strong wind gust of 100 km/h is expected on October 7 and 8, marking the beginning of autumn. This wind speed is powerful enough to exert significant force on open window shutters. According to calculations, a 100 km/h wind exerts a dynamic pressure of about 473 Pa, or roughly 48 kg per square meter. For a typical 1.5 m² shutter, this translates to a force of approximately 80 to 95 kg—similar to the weight of two 35 kg cement bags. This calculation uses the formula for dynamic pressure, q = ½ × ρ × v², where ρ is the density of air at sea level (1.225 kg/m³) and v is the wind speed in meters per second (100 km/h equals about 27.8 m/s). Applying this formula, the dynamic pressure at 100 km/h is around 473 Pa. For a 1.5 m² shutter, this results in about 72 kg-force without considering a drag coefficient. When a coefficient of about 1.2 is included, the force increases to approximately 87 kg-force. Real-world shutters typically have a coefficient between 1.1 and 1.3, leading to a force range of 80 to 95 kg. The force from wind does not act at a single point but is spread across the entire surface of the shutter and passes through two hinges, which act as pivots. The wider the shutter, the longer the lever arm, increasing the load on the hinges and their anchorages. A shutter folded against the wall and held by its stop offers the wind a different grip compared to one that remains open. When open and poorly stopped, the shutter ends up in a cantilever position over two attachment points. Additionally, a poorly stopped shutter can slam, and each impact against the stop adds a dynamic force to the static thrust, which hinges and fastenings must absorb. Flat surfaces, two hinges, and sometimes a worn stop contribute to the shutter accumulating multiple stress factors. This combination explains why shutters are often among the first facade elements to give way under strong wind. The safest action is to close and lock the shutters. If they are to be left open, they should be properly secured on their stops, ensuring they hold firmly so that no panel can move. This advice also applies to shutters on rarely used rooms, which are often overlooked. A minor note on the calculation: some presentations of Eurocode use a slightly higher air density, ρ = 1.25 kg/m³, instead of 1.225. At 100 km/h, this changes the pressure from approximately 473 Pa to 483 Pa, a difference of about 2%.