Striations Clouds

The most effective way to determine tornado occurrence is by observing the clouds closely. They not only help in predicting tornadoes but they also give you an idea as to the severity of an upcoming tornado. One cloud formation that signals impending tornado is striations clouds. But what are striations clouds? How do they look like and what do these clouds tell about the impending tornado? Read on to find out.

Striations clouds refer to the bands of clouds surrounding the updraft tower that suggest the presence of cyclonic rotation. These clouds are arranged parallel to the airflow relative to the main cloud phenomenon. They exhibit a corkscrew effect visible on the swirling updraft of a LP storm (low-precipitation supercell). Striation cloud is the signature cloud searched for by storm chasers to confirm tornado development as radar identification is difficult under LP storm due to the absence of heavy precipitation base. Striation clouds may signal small and fleeting tornado but they produce prolific hailstorms.

At What Height is Striations Clouds Found?

Striations cloud is often noted in the spinning LP supercell updraft. But how far is it from the ground? A thunderstorm’s updraft is marked by a rain-free base, an area of dark, smooth and flat cloud base with no precipitation, and is found less than 6,000 feet from the Earth’s surface.

How do Striations Clouds Form?

Striations clouds form as a result of the pushing of warm air upwards causing wind shear in the upper cloud level. Low pressure system, the result of the collision of humid and dry air on or near the dry line region, gives rise to the lifting of warm air. As the warm air rises, it condenses and moves smoothly in gentle slopes as evidenced by the smooth striations clouds arranged parallel to the airflow. LP storms may produce little precipitation, or they may generate large hails and short-lived, yet damaging, tornadoes.

What do Striations Clouds Look Like?

These clouds exhibit a barber pole or corkscrew pattern encircling the updraft of a low precipitation thunderstorm. Because there is minimal or no precipitation at all, they tend to display a clear, grayish appearance. However, striations clouds usually produce large hail, thus, making them really dangerous.

How common are Striations Clouds?

Striations clouds are common in areas where low precipitation supercell thunderstorms develop. In the U.S, LP storms are very common in the Central Plains. They are often spotted during the spring and summer months in the northwestern part of Texas, southwest of Oklahoma, as well as other parts of Central Plains.

Undeniably, knowing how striations clouds develop and appear is very important in forecasting tornado occurrence and nature.

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