While athletes look for columns or bubbles of rising warm air (thermals) when flying, there are other forms of lift when skies are overcast and thermal activity is weak. When the wind hits a slope, it is forced upwards, creating a lift band which athletes can use to soar along a ridge. Lift is also created where two air flows converge, for example where two valleys meet. When conditions are poor, the athletes will be looking for any lift they can find.