Dubai floods and cloud seeding
by Kirsty McCabe, FRMetS
In April 2024, over a year’s worth of rain fell in just a single day, submerging the normally arid Gulf region and sparking tales of cloud seeding.
The rains began late on Monday 15 April 2024, intensified the following morning and the storms continued throughout Tuesday, affecting the United Arab Emirates, Bahrain, Qatar, Saudi Arabia and Oman.
The National Centre of Meteorology recorded the highest rainfall in the Khatm Al Shakla area in Al Ain, reaching 254 mm in less than 24 hrs. Meanwhile, more than 142 mm (5.6 inches) of rain soaked Dubai itself, around as much as normally falls in a year-and-a-half at Dubai International Airport, where the annual average is 97 mm and the average for April is only around 8 mm.
Dubai Airport enjoying a light shower 👀✈️ pic.twitter.com/4g9pEf3RKg
— Breaking Aviation News & Videos (@aviationbrk) April 16, 2024
As well as affecting flights at one of the world’s busiest airports, motorways and homes were flooded, schools were shut, and people were forced to work from home. Sadly, the storms also led to over 20 fatalities with vehicles swept away by the floodwaters in the UAE and Oman.
This part of the world is characterised by long, dry spells with irregular bursts of heavy rain and flash floods, but 16 April 2024 may well be the region’s wettest April day on record. The Emirates News Agency described it as a “historic weather event” that surpassed anything seen since records began in 1949.
Clusters of storms
The culprit behind the extreme rainfall is likely to be a mesoscale convective system. MCSs are formed when a team of individual thunderstorms cluster together and cover a large area, from a few hundred to a few thousand kilometres wide, and typically last for several hours or even days, bringing heavy rainfall, hail, lightning, strong winds and even tornadoes and dust storms.
Dubai: Timelapse of the massive storm that caused a historic flood. pic.twitter.com/tackWMYJzO
— Pagan 🚩 (@paganhindu) April 17, 2024
Roughly 4 or 5 MCS events occur each year in the Middle East, triggered by low-level wind convergence, moisture advection from the Arabian Sea, Arabian Gulf and/or the Red Sea, and a cold anomaly in the mid-troposphere usually caused by a cut-off low. An equatorward displacement and strengthening of the subtropical jet helps increase the lifetime of the system.
Back in March 2016 , a previous MCS event hit UAE and Oman, bringing over 240mm (9.45 inches) of rain and winds of up to 126 km/h (78.3 mph) to Dubai.
A study published in Atmospheric Research analysed 95 events that occurred over the southern Arabian Peninsula from 2000 to 2020, and found that MCSs occur more frequently in March and April. The study also found an increase in the duration of MCSs over the UAE over the 21-year period, suggesting that such extreme rainfall events may be even more impactful in a warming world.
And April 2024’s flash flooding was certainly extreme, with so much rain falling at once that even the infrastructure and drainage systems designed to withstand these types of events simply couldn’t cope.
What about cloud seeding?
Luckily the storms were well forecast, up to a week in advance, showing just how important early warning systems are. However, the intensity of the downpours did spark stories about cloud seeding.
Yes, the UAE does have an operational cloud seeding programme, not a surprise given the predominantly arid nature of the region. Cloud seeding usually involves spreading fine particles into individual developing clouds that wouldn’t normally lead to rain. Small planes burning salt flares fly through the developing clouds, hoping that the tiny particles produced will act as cloud condensation nuclei and trigger the formation of water droplets and eventually rain.
But in this case, the clouds were part of a large weather system advancing across the region, and already predicted to produce substantial amounts of rain across a wide area. Any possible effect from cloud seeding would be tiny in comparison. So the tales of cloud seeding simply don’t make sense, and are a distraction from the most likely guilty party — climate change. The UAE National Centre of Meteorology later confirmed that no cloud seeding mission had taken place.
And finally, in case you’re wondering whether we get MCSs in the UK, we do, typically only once or twice a year when a plume of warm air comes up from Spain.
