At a Glance
- A lone cumulonimbus cloud appeared over Galveston, Texas, on Wednesday evening.
- The cloud was associated with a thunderstorm some 45 miles away in Houston.
- It was unique as it was by itself among otherwise clear skies.
Residents of Galveston, Texas, were treated to the breathtaking sight of a lone cumulonimbus cloud associated with a thunderstorm dumping rain over Houston on Wednesday.
A cumulonimbus cloud is a towering, vertical cloud containing a thunderstorm, forming from water vapor being forced upward by powerful upper-air currents.
These clouds can form in squall lines, in clusters or alone, as the one did Wednesday. They are capable of producing thunder, lightning, hail, strong winds and tornadoes.
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In this case, the cumulonimbus cloud was associated with a thunderstorm that was dumping heavy rain over parts of the Houston metro area, some 45 miles to the northwest.
It was the very definition of what meteorologists refer to as "isolated thunderstorms." As you can see on the radar image above, there were no other thunderstorms around the Houston and Galveston areas at the time.
In fact, skies were mostly clear outside of this one thunderstorm in southeastern Texas.
Brian Donegan is a meteorologist at weather.com. Follow him on Facebook, Twitter and Instagram.
