Suhail star signals end of UAE summer but Sweat-tember and Hot-tober loom

End of summer approaches but discomfort persists

Residents of the United Arab Emirates can expect a signal of seasonal change next week as the star Suhail makes its first appearance in the predawn sky. According to the Emirates News Agency (WAM), citing the Emirates Astronomy Society, and confirmed by the society's chairman, Ibrahim Al Jarwan, to The National, the star is expected to become visible on Monday, 24 August. Known internationally as Canopus, Suhail's annual return has traditionally signified that the peak of summer is beginning to recede in the Arabian Peninsula.

Despite the symbolism, the change is not immediate. Al Jarwan told WAM that temperatures generally remain high through the end of September, while humidity increases and early-morning fog begins to form. Between 1991 and 2020, September averages ranged from 29°C to 39°C with approximately 54 per cent humidity, as reported by The National. This means that although temperatures will cool slightly compared with previous months, being outdoors will not necessarily feel more pleasant. As The National put it, the slight cooling is 'more than balanced out' by greater humidity.

Al Jarwan also noted to WAM that temperatures in the UAE begin a gradual decline after 20 August, but hot weather persists through September. For those watching for the arrival of Suhail, the first day will not bring a sudden drop in temperature.

Suhail, known astronomically as Canopus, is a giant, yellowish-white star located in the constellation Carina. It is about 313 light years from Earth, according to The National. It is also described as the second-brightest star in Earth's night sky after Sirius, as noted by Nasa, and can be seen with the naked eye. A separate distance figure of approximately 310 light years was cited in the Saudi Press Agency's announcement of Suhail's arrival.

The star is also named the Star of Yemen, and its appearance aligns with the ancient Al Drour calendar, which divides the year into 100-day phases. Arab folklore holds that 'The night cools down when Suhail rises', a saying that underscores the cultural significance of the celestial event.

However, astronomical explanation clarifies that Suhail does not itself cause temperatures to fall. As reported by WIRED Middle East, Suhail is a seasonal marker rather than a mechanism controlling weather; its reappearance coincides with a stage of the seasonal cycle as daylight decreases, and Earth's axial tilt causes our seasons.

Viewing the star

For those hoping to spot Suhail, Aljarwan told WAM that the star can be observed approximately 40 minutes before sunrise, low above the southeastern horizon. This will be its first appearance after disappearing in early May and remaining out of view for about three and a half months. The precise timing varies by emirate, as sunrise differs slightly across the country. Viewers should arrive about an hour before local sunrise to find a suitable spot and then search the southeastern horizon 40 minutes before sunrise.

If haze or cloud obscures the star on the first morning, observers can try again on subsequent days because the star will rise progressively earlier. The appearance on 24 August marks the start of Suhail's visible predawn appearance in the central Arabian Peninsula, not a one-night event.

Suhail will emerge near the horizon, where buildings, mountains, artificial light and atmospheric haze can obscure it. However, it is visible to the naked eye in the Middle East, as the region is far enough south to observer Suhail, while locations above approximately 38 degrees north of the equator have a harder time seeing it. A compass or sky-map apps such as Stellarium, Sky Tonight, or Sky Guide can help identify it, as those apps list the star as Canopus.

No official Suhail viewing sites have been announced in the UAE, but darker locations with open southeastern horizons can provide better visibility. Suggested options include Al Qudra, Al Marmoom, Al Wathba, Al Quaa, Mleiha, Liwa, and areas around Jebel Jais, according to WIRED Middle East. Those traveling into the desert before dawn should use established roads unless equipped for off-road driving, park in safe zones, and share their destination with someone else, along with an expected time back.

Safety guidance from Nasa notes that binoculars, telescopes, or cameras with magnifying lenses should never be pointed at the sun because doing so can cause severe eye injury. This is especially relevant for early-morning viewing sessions that extend into sunrise, when the sun begins to rise above the horizon.

Temperatures ahead

Despite the end-of-summer connotations of Suhail, peak temperatures remain for weeks. Climate data from the last three decades illustrates this trend. For September, minimums average around 29°C and maximums 39°C, with 54% humidity. October follows with an average minimum of 25.5°C and a maximum of 35.8°C, as reported by The National. The coolest month is traditionally January, with 1991–2020 data showing an average minimum of 15.5°C and maximum of 24.3°C.

UAE summer heat may be typical, but the arrival of Suhail marks the beginning of a slow transition. While the star's presence reappears on the evening horizon, the weather will still be hot and humid for weeks to come; however long-term cooling gradually sets in by November, when winter begins according to the calendar.

Historical use

For generations, communities across the Arabian Peninsula used Suhail in what WIRED Middle East describes as a natural calendar. It was part of the folklore of farmers, fishermen, herders, and travelers planning seasonal activities. Similarly, the tradition of the 100-day phases of the Al Drour calendar adds to this astronomical and agricultural heritage.

As tradition says, the night cools when Suhail rises. But the actual cooling takes time, and the humidity of September ensures that the end of summer is felt more than seen in the first weeks.