Saudi Arabia | Warning of possible downward winds and dust waves in areas of thunderstorm activity during the next 48 hours.

Arab Weather - Sinan Khalaf - The weather forecast staff at the Arab Regional Weather Center warned of sandstorms and dust waves that may be caused by downward winds associated with thunderstorms in parts of central and eastern parts of the Kingdom during the next three days, including the capital, Riyadh, warning of a low risk. The extent of horizontal visibility and perhaps its absence in some periods, depending on the strength of the clouds.

How do downwinds arise?

Its speed can exceed 200 km/h

Sandstorms are sometimes formed as a result of what is known climatically as “ downward winds ”, which are strong winds that fall from the cumulus cloud and strike the ground vertically, resulting in a dust wave that spreads in a circular motion and expands and takes the form of a huge, majestic brown cloud.

The downward wind arises due to the difference in the density of the air below the cumulus cloud. When it rains, the raindrops evaporate under the cumulus cloud before it reaches the ground, so the air in that part cools dramatically and becomes denser and heavier than the air around it, and it falls as a descending mass in the form of winds called “ the downward wind .” And it hits the earth with a destructive force sometimes and at a speed that may exceed 200 km / h, which leads to the formation of dust waves whose density and strength vary according to the strength and intensity of the winds descending from the cumulus cloud.