Evolutionary tracks of clouds that condense out of the hot halo. Solid curves correspond to the median while the shaded bands show the 16th-84th percentile regions. Colors correspond to different epochs where the cloud first came into existence. In all cases, the origin of the cloud can be traced back to a ‘cold seed’, typically comprised of only a few gas cells. Following that, clouds accrete matter to grow to a median mass of ∼10^5.2 M_⊙ by z = 0. The percentile regions, however, are broad, implying that evolutionary tracks of individual clouds can be diverse.