Overshooting thunderstorm tops occur when a
strong
thunderstorm updraft has enough momentum to caryy rapidly
rising
parcels of air past their equilibrium level at the
tropopause:
Visual examples:
Diagram:
On satellite imagery overshooting tops cast shadows nearby
if the sun
is low in the sky. Therefore they are best seen early
in the
morning or late in the afternoon. The overshooting top
takes up
only a small portion of the entire area covered by the
cirrus anvil.