Downdrafts have been affecting the Kingdom for some time. What do you know about them and the scientific reason for their occurrence?

Arab Weather - The Kingdom has been affected since the beginning of December by a high pressure system in all layers of the atmosphere, which, God willing, will impose stable weather conditions and temperatures higher than their usual rates for this time of year.

The high pressure system controlling the region is accompanied by descending currents that impose stability on the atmosphere.

Experts at Arab Weather said that the high pressure system is characterised by characteristics that impose stable weather in any region it affects, the most important of which are the descending currents that impose stability on the atmosphere. So what is the high pressure system? What are the descending currents that accompany it?

High pressure: It is a part of the air above a certain area of the earth that is characterized by a higher pressure than the air pressure in the surrounding areas, where the highest value of the air pressure is in the center and decreases the further away we are from the center, and the direction of the winds is clockwise in the northern hemisphere and the opposite in the southern hemisphere, and high pressures are always accompanied by descending winds and complete stability in the atmosphere.

What are the downdrafts that accompany high pressure?

Downdrafts are the descent of cold air from above and its compression, thus increasing its temperature with increasing pressure. The descent of cold air from the upper layers of the atmosphere to the Earth's surface usually stabilizes the atmosphere and prevents the formation of clouds. Thus, the sky on high-pressure days is usually clear, with some times when there are quantities of high, rainless clouds. This is the opposite of what happens in low-pressure systems, where warm air rises to the upper atmosphere, cools, and then condenses, forming clouds and precipitation.

Characteristics of high pressure:

• Presence of downdrafts
• Clear and mostly sunny
• Atmospheric pressure values increase as we move towards the center of the high pressure system.