Any long and flat gear when carried on the roof of your vehicle can act like a sail. Due to the way air flows over certain vehicles, this can increase the effects of updraft. With this in mind and for the safety of yourself and others, ensure all loads are secured properly.
When loading your surf gear or kayak, ensure that it is mounted correctly using the tiedowns provided and is positioned centrally, parallel to the vehicle.
Ensure carried gear is properly secured front and back (e.g. kayaks), where appropriate.
During long journeys, regularly check your gear and retighten all secure points.