Five in the morning is the earliest hour that is genuinely usable here. In the third week of June the sun is up shortly after 5:30 am, which makes this the start of the only comfortable stretch of a summer day — the beaches, the cycle tracks and the running loops all have people on them before six.
It is also the hour the public transport day begins on a weekday, so a five o'clock countdown is often about being on the first train rather than the second, particularly for a commute that crosses an emirate boundary.
In winter the same hour is fully dark, with sunrise still two hours away, and the people counting towards it are heading for work rather than for daylight. The countdown resets every twenty-four hours and always points at the next 5 am.
Common questions
Is it light at 5 am in the UAE?
In June, almost — sunrise is shortly after 5:30 am. In January it is fully dark, with sunrise still two hours away.