Astronomical calculations have revealed that the autumn season will begin on Friday, September 23, lasting 89 days, 20 hours and 44 minutes.
After the sun passes the summer solstice, the apparent movement of the sun begins to gradually move towards the south, and the slope of its rays decreases, until it reaches zero around the 23rd of September (the autumnal equinox) and the sun’s rays perpendicular to the equator.
This day will be the same length for night and day in all places of the globe, and autumn occurs in the northern hemisphere and spring in the southern hemisphere.
The four seasons occur as a result of the Earth’s rotation around the sun and the inclination of its axis on the plane of its orbit.
Autumn is a transitional season from the heat and humidity of the summer to the rain and coldness of winter.
The autumn climate is characterized by moderate temperatures, but it is punctuated by some cases of instability in weather conditions.
These conditions may include air depressions centered on the Mediterranean Sea, accompanied by instability in the upper layers of the atmosphere, causing heavy rains sometimes on the northern coasts, Lower Egypt and Cairo.
The southern parts of the country, the Red Sea Governorate and South Sinai are sometimes affected by the extension of the seasonal Sudan depression, which leads to high humidity and heavy rains, which cause torrential rains in the mountainous areas of Sinai and the Red Sea mountains and the south parts of the country.