Several people took to social media Tuesday evening to share pictures of a shelf cloud that was part of squall line thunderstorms that moved through the county.
According to the National Weather Service, “a shelf cloud will usually be associated with a solid line of storms. The wind will come first with rain following behind it. It may appear to rotate on a horizontal axis.” The NWS says that often a shelf cloud is reported as funnel clouds, rotation, or a wall cloud, but “wall clouds will rotate on a vertical axis, sometimes strongly. The wall cloud is much smaller and more compact than a shelf cloud and is usually under a rain free cloud base.” A shelf cloud will also cover the entire horizon.
It is important to note the difference between a wall cloud and a shelf cloud as a wall cloud is associated with storms where the main hazard is tornadoes, while shelf clouds are a part of the squall line and the main hazard is the high winds that precede the rain. The National Weather Service says that brief spin-up tornadoes are possible along squall lines with shelf clouds, but are generally “rain-wrapped and short-lived”.
National Weather Service Information from weather.gov.
Pictured Above: Squall line with shelf cloud over Trenton, taken near Ingles Drive and S. Main Street intersection. Courtesy of Jerry Gregory.
Pictures in Gallery: Pictures 1 and 2 courtesy of Jennifer Hartline and were taken on Sand Mountain. Picture 3 courtesy of Brooke O’Bannon and was also taken on Sand Mountain.