September weather forecast
Jeddah, Saudi Arabia

September marks the beginning of slightly less heat-intense months in Jeddah, with temperatures easing into the high 30s, to reach a peak of 37.6°C (99.7°F). Witness a shift in the weather patterns as the daylight hours reduce further, signalling a gradual descent into the cooler periods of the year. UV levels remain high during this time and adequate sun protection is still necessary for any outdoor activities. The upcoming months usher in a significant change, as the city prepares for cooler autumn temperatures.

Temperature

The commencement of September in Jeddah brings an average high-temperature of a still torrid 37.6°C (99.7°F), marking an inconsequential divergence from August. During September, the average low-temperature in Jeddah is a warm 26.4°C (79.5°F).

Heat index

For September, the heat index is estimated at a blazing hot 58°C (136.4°F). Warning: These weather conditions are identified as gravely perilous, heatstroke is near.
Factoring in the heat index, values are geared towards shaded areas with light breezes. A direct sunlight exposure may boost the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', reflects the blend of air temperature and relative humidity to give a temperature impression. Additional elements encompassing metabolic differences, the degree of physical activity, and attire can impact the individual's perception of temperature. In the direct sunlight, the weather's impact can be amplified, possibly boosting the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for children. Young ones are generally at greater risk than adults due to their limited sweating ability. In addition, their large skin surface relative to their small bodies and higher heat production from their activities add to their vulnerability.
The human body keeps its cool primarily through perspiration, as this process enables sweat to evaporate, taking away the excess heat. During high air temperature and humidity (high heat index), the process of perspiration is hindered, intensifying the sensation of heat. Accumulating heat beyond the body's cooling measures leads to rising temperatures and potential ailments.

Humidity

With an average relative humidity of 67%, September is the most humid month in Jeddah.

Rainfall

Throughout September, in Jeddah, 0mm (0") of precipitation is accumulated. During the entire year, Jeddah aggregates up to 61mm (2.4") of precipitation.

Sea temperature

In Jeddah, Saudi Arabia, the average seawater temperature in September is 31.1°C (88°F).
Note: It is often said that swimming in waters above 30°C (86°F) can feel less revitalizing.

Daylight

In Jeddah, the average length of the day in September is 12h and 16min.
On the first day of September, sunrise is at 06:06 and sunset at 18:39. On the last day of the month, sunrise is at 06:14 and sunset at 18:11 +03.

Sunshine

In September, the average sunshine in Jeddah is 10h.

UV index

The months with the highest UV index are April through September, with an average maximum UV index of 12. A UV Index estimate of 11, and higher, represents an excessive health risk from exposure to the Sun's UV rays for ordinary individuals.
Note: In September, a daily UV index of 12 turns into the following recommendations:
Undertake every vital safety procedure, as unprotected skin and eyes could sustain burns in no time. UV radiation from the sun is at its strongest between 10 a.m. and 4 p.m. Try to limit direct exposure during these hours. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense. Sunscreen of at least SPF 30 should be applied generously and reapplied often on overcast days, especially post swim or outdoor exercise. Caution! The Sun's UV rays become stronger due to reflections from water and sand.