This disclosure is directed to air-bearing sliders used in magnetic storage systems that employ a trench arranged between a transducing head connected to a slider body and a leading edge of the slider body. A drive unit for the transfer member is controlled by a driving signal from a first controller. A probability may be associated with each critical threshold level in order for the weather module to determine whether the likelihood that a critical threshold level will be exceeded meets or exceeds its associated probability. As a result, the total surface area of the inner face is relatively small.