The heavy traffic today was primarily due to multiple accidents reported on major routes in the UAE, especially on Emirates Road E311 and E611, causing severe congestion and slowdowns during the morning rush hours. There were significant traffic buildups near areas like Bu Shaghara, Al Nahda, Deira, Sahara Centre, Al Qusais Area 5, and Ras Al Khor. Drivers were advised to use alternative routes due to these incidents.

In addition, specific localized bottlenecks such as the one between Natipora crossing and Barzulla also contributed to traffic jams in some regions by forcing vehicles to take longer or congested routes.

Major event-related traffic impacts and street closures, such as those for conferences or sports events in cities like San Francisco, can also significantly increase congestion on certain days, though not confirmed as the cause today specifically.

Overall, the main cause for today's traffic congestion was multiple accidents combined with bottlenecks on critical roads, leading to extensive delays and heavy congestion in affected areas.