Probabilities of the three origin channels as a function of line-of-sight velocities of clouds in the frame of the local standard of rest. The vertical dashed lines delineate commonly used definitions to classify clouds in the Milky Way halo. Outflowing clouds predominantly trace cold gas arising from the central in the recent past (≲2 Gyr), while their inflowing counterparts typically condense out of the hot phase. Clouds ejected from satellites are relatively rare (≲5%), but roughly equally likely at all (line-of-sight) velocities.