A method comprises measuring pressures at a number of locations along a drill pipe of a drill string positioned in a wellbore, using a number of pressure sensors that are positioned on or within the drill pipe at different depths of the wellbore. The method includes determining a first pressure gradient between measured pressures measured by a first pair of pressure sensors of the number of pressure sensors and determining a second pressure gradient between measured pressures measured by a second pair of pressure sensors of the number of pressure sensors. The method includes determining a pressure gradient change based on a difference between the first pressure gradient and the second pressure gradient; and identifying that a downhole condition has occurred based, at least in part, on pressure gradient change.