partial view of a shelf cloud (updraft), with a rain shaft (downdraft) visible behind it
<p>Shelf clouds are formed when a downdraft of cool air (microburst behind shelf cloud) forces warm air in the surface to rise, this updraft of warm air then becomes saturated with moisture and condenses, forming the shelf cloud.
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After going through this shelf cloud, the temperature dropped from 27-28°C to 19-20°C (7-9°C degree drop
<a href="//commons.wikimedia.org/wiki/User:Rollcloud" title="User:Rollcloud">Rollcloud</a>
CC BY 2.5
<span class="int-own-work" lang="en">Own work</span>