‘What’s that funny looking cloud?’ It’s more common than you may think!

Mentone rain shower, June 14, 2017 at 1:45pm. (Photo: Skeeter Logan)

During the summertime, hit-and-miss showers and storms bubble up during the heating of the day and dump torrential rain over the land that is lucky enough to receive it.

Often, these isolated storms are surrounded by areas of blue skies and sunshine, which means that different portions of the rainstorm are featured.

Cumulonimbus clouds

Check out this time lapse of a cumulonimbus cloud as it developed over Winchester. The cloud was captured on the WHNT News 19 tower cam located on the roof of the station in downtown Huntsville, about 35-40 miles away.

Time lapse of a cumulonimbus cloud that developed over Winchester, as seen from Huntsville.

A cumulonimbus cloud (sometimes known as a “thunderhead”) develops when warm, humid air becomes less dense than the air surrounding it, causing it to rise. As a result, the rising air cools, and the water vapor within it condenses into the puffy, cotton ball-looking clouds, known as “cumulus clouds”.

“Rain shower just north of Harvest 6/13/17. Shot from Phantom 3 Drone.” (Photo: Jeff Sinclair)

But as air continues to rise and condense, the clouds become taller and taller, eventually reaching a level of the atmosphere in which the upper-level winds blow the tops of the clouds outward. This outward structure is known as the “anvil”. Eventually, rain begins to fall, and the cloud could be considered a cumulonimbus (“cumulo” is Latin for “heaping/accumulating” while “nimbus” is Latin for “rain”).

Rain “curtains” (also known as “rain shafts”)

As the rain falls from the cumulonimbus clouds, you may be able to see it fall as close as across the street to as far away as several miles.

Looking Southwest From East Taft, TN. (Photo: Beth B)

The rain falls as a continuous sheet, and it can appear dark or light, depending on the angle of the sunlight. These features are known as rain “curtains” or “rain shafts”, and while they may resemble a tornado at times, they are actually harmless themselves during “ordinary” thunderstorms.

During strong to severe thunderstorms that can produce damaging straight-line winds, you may see the rain fall out of the cloud in a “burst” before fanning out in all directions. The “fan” is known as a “rain boot”.

Microburst dropping rain over south Huntsville shortly after 6pm Monday, August 1, 2016.

Stay dry amongst the hit-and-miss rain showers

Now that we are in mid-June, we can expect to see more hit-and-miss showers and thunderstorms in the Tennessee Valley (click here to read the latest forecast discussion, as well as the updated forecast for how likely the rain will impact your weekend).

Another great tool to use when dodging the rain is our Live Alert 19 app, which is free for both Apple and Android devices. The Live Alert 19 app will alert you if rain is detected near your location, and it will even alert you to lightning. You can lean on the app to help determine whether or not an outdoor activity should be cancelled, or if the rain will only be a small nuisance. Click here to learn how to download Live Alert 19 to your device.