September weather forecast
Cairo, Egypt

The weather in September straddles between the relentless Egyptian summer and the more bearable autumn. After the furnace-like heat of the summer months, September brings welcome relief even though the average high hovers around 32.6°C (90.7°F). Rainfall remains minimal, but the decrease in temperature and stabilization of humidity signal the end of the scorching summer. With the arrival of cooling October winds, Cairo's weather enters a much-anticipated fall.

Temperature

Cairo experiences an average high-temperature of a still hot 32.6°C (90.7°F) with the onset of September, subtly varied from August's 34.2°C (93.6°F). During September, Cairo detects a significant contrast from its daytime temperatures, with nights averaging at an agreeable 20.5°C (68.9°F).

Heat index

For September, the heat index is evaluated at a torrid 39°C (102.2°F). Extra safeguards are necessary to prevent heat exhaustion and heat cramps. Prolonged activity might cause heatstroke.
One should consider that heat index numbers are for shaded settings and light wind. Exposure to the direct sun might augment heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', joins air temperature with relative humidity to produce a temperature perception for humans. A person's impression of weather can be shaped by many aspects, among them metabolic variations, pregnancy, and levels of physical activity. By being directly under the sun, it's possible for the felt temperature to increase by 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for children. Children often lack awareness of the importance of taking breaks and rehydrating. The feeling of thirst is a late indication of dehydration, so maintaining hydration, especially during long periods of physical activity, is critical.
The evaporation of sweat is a natural cooling mechanism of the human body, facilitated by perspiration. In situations of high air temperature combined with high humidity (significant heat index), the body's ability to perspire is reduced, heightening the sense of warmth. Should the body fail to balance its heat gain, the escalating temperature poses health challenges.

Humidity

In Cairo, the average relative humidity in September is 60%.

Rainfall

July through September are months without rainfall.

Daylight

In September, the average length of the day in Cairo, Egypt, is 12h and 20min.
On the first day of September, sunrise is at 6:32 am and sunset at 7:17 pm. On the last day of the month, sunrise is at 6:48 am and sunset at 6:41 pm EEST.

Sunshine

In Cairo, Egypt, the average sunshine in September is 10.4h.

UV index

In Cairo, the average daily maximum UV index in September is 9. A UV Index estimate of 8 to 10 represents a very high health vulnerability from exposure to the Sun's UV rays for the average person.
Note: A typical high UV index of 9 in September suggests the following recommendations:
Always safeguard yourself; without protection, skin and eyes can get damaged instantly. From 10 a.m. to 4 p.m., when UV radiation is at its strongest, limit direct exposure to the Sun and note that shade structures may not provide full sun protection. A hat with a broad brim is indispensable, filtering out up to half of UV rays. Apply generously and frequently a broad-spectrum SPF 30+ sunscreen every two hours, or immediately after swimming or any outdoor exercise.