Jordan: After its absence from the Kingdom... the Khamaseen depressions wake up from their slumber (why are they active during this period and what are they associated with? Find out the details)

Weather of Arabia - With the first day of spring astronomically and the beginning of the vernal equinox every year, the season of activity of the spring type of weather depression, which is the Khamsin depression, begins, which brings with it a clear rise in temperatures and dust at the beginning, then it is followed by a sharp decrease and sometimes muddy rain, but it was It is noted that this season witnessed a significant weakness, close to non-existence, in the activity of the Khamasinah depressions over the Kingdom, in complete contrast to what was happening in previous seasons and years, but it is expected, God willing, that the Khamasinah depressions will wake up from their slumber and return to activity and influence on the Kingdom during the coming period, which is, of course, within the season. Or the normal period of activity.

Are the Khamaseen depressions and why did they return to activity again after their prolonged absence from the Kingdom?

Khamasinian depressions are known as a type of barotropic depression. They are active in the spring and usually originate in the Algerian desert east of the Atlas Mountains. Then they move towards the east until they reach the Mediterranean region and sometimes continue their way towards the countries of the Arabian Gulf. This type of depression is formed. The weather is a result of the increased heating of the land, and because of the difference in specific heat between the land and the water, as the surface of the waters of the Mediterranean Sea remains cold, and the land becomes warmer. Thus, the air on land begins to expand, its weight decreases, and the atmospheric pressure decreases, announcing the formation of a Khamasinian depression in the African Sahara.

Specialists at the Arab Regional Weather Center believe that the main reason for the return of the activity of the Khamsin depressions (although their activity is below average) is due to changes in the shape of the weather systems represented by the increase in the growth of hot air masses over the African continent due to increased solar heating processes. The reasons cannot be limited to that only, but We can say that the main reason for the return of its activity is closely related to the increase in surface heating processes of the land.

Why is this type of depression called pentagonal depression, and what is its period of activity?

This type of depression has been called "Khamsinian" because its period of activity extends from the beginning of the spring solstice on March 21 of each year, until May 10 of each year. Khamsinian depressions may begin their activity before the specified date from year to year, and are called At that time, the “semi-Khamseen” atmospheric depressions were used.

Weather and temperature fluctuations accompanying the Khamaseen depressions (hot weather, dust, and sometimes unstable weather and local muddy thundershowers)

Specialists at the Arab Regional Weather Center say that the Khamsina depressions at the front are usually accompanied by the rush of an air mass with temperatures much warmer than usual (hot), and some of the air masses rushing at the front of the Khamasina depressions are sometimes very hot and cause heat waves to occur in some countries. North Africa, the Levant, and the Arabian Peninsula, and at the forefront of the Khamaseen weather depressions, the Khamaseen weather conditions prevail, represented by dry, warm (or hot), and dusty weather.

But soon the Khamasin depression moves away, and an air mass with lower temperatures rushes behind it, causing a sharp drop in temperatures in a period of time that may not exceed 24 hours sometimes, and the atmosphere may turn from hot to cold in a short period of time.

Sometimes the Khamseen weather depressions coincide with the approach of a cold air mass in the upper layers of the atmosphere (upper waves or cold upper troughs), and then there is a meeting between the warm, dry air currents in the lower layers of the atmosphere with the cold ones in the upper layers of the atmosphere, resulting in a state of instability. The weather leads to thunderstorms that are often muddy as a result of rain mixing with dust resulting from the Khamaseen depressions.

In the event that one of the pentagonal depressions moves (depending on the shape of the systems) from the north of the African continent towards the south of the European continent and there is an weather condition represented by the presence of a cold air mass, especially towards Turkish territory, the pentagonal depressions then attract cold air towards them and transform from barotropic systems to baroclinic systems, that is, they are accompanied by fronts. Cold air.

God knows.