Understanding atmospheric dynamics of the 2024 Arabian Gulf flood: Can extreme rainfall be predicted weeks ahead?
摘要
In April 2024, an extraordinary rainfall event delivered over a year’s worth of precipitation within a single day, inundating the Arabian Gulf region. This extreme event affected the UAE, Bahrain, Qatar, Saudi Arabia, and Oman, with notable records such as rainfall of 254 mm in Al Ain and 142 mm in Dubai in less than 24 h—far exceeding the region’s annual averages. This study investigates the dynamic processes driving the event, emphasizing the interplay of atmospheric mechanisms behind the deep convection. Key contributing factors included a stationary high-pressure system over the Indian Ocean interacting with an eastward-moving low-pressure system over the Arabian Peninsula, a strengthening mid-level trough that evolved into a cutoff low, and a pronounced upper-level PV intrusion associated with Rossby wave-breaking and a southward-shifted subtropical jet. The predictability of this extreme rainfall event was evaluated using convection-permitting regional modeling and subseasonal ensemble forecasts. Results indicate that short-range convection-permitting simulations realistically captured the event structure within several days of the onset. At longer lead times, a subseasonal ensemble forecast at convection-permitting resolution provided probabilistic guidance, showing a 60–80% probability of heavy rainfall two weeks in advance. This study highlights the critical role of subseasonal ensemble prediction in understanding atmospheric dynamics and advancing early detection of extreme weather events, offering early interventions and disaster preparedness.