Buses taking on water, collapsing walls and heavy traffic frustrated Istanbulites on Monday as downpours and flash floods gripped the Turkish megalopolis.

In the early hours of Monday, downpours began hitting the European and Asian sides of the city during rush hour. Streets and roads at lower altitudes that lack drainage were submerged with rainwater which also inundated some shops. The Grand Bazaar, the city's most famous and historic marketplace, was also hit by floodwaters while shopkeepers struggled to clean up their shops in the market and the nearby shopping district Eminönü. The main road in Eminönü was also clogged due to floodwaters.

In Fatih, where Eminönü and the Grand Bazaar are located, downpours ripped apart pavement stones, blocking a street, while rainwater overflowing from clogged drainage pipes flooded the streets elsewhere. In the Yenikapı district, two vehicles were trapped in a flooded underpass, with firefighters helping the stranded drivers.

In Sarıyer, raging waters from the Bosporus combined with floodwaters inundated a main coastal road while the Kağıthane stream almost overflowed its banks on the European side of the city. Two vehicles fell into sinkholes when streets collapsed due to floodwaters in the Gaziosmanpaşa and Avcılar districts.

In Beykoz on the Asian side, the retaining wall of a restaurant collapsed, trapping a worker. Also in Beykoz, the Küçüksu neighborhood was inundated with floodwaters. On the Asian side, which was more affected by the rainfall, footage on social media showed floodwaters filled some passenger buses while underpasses to metro services were also filled with water, proving a hurdle to commuters trying to reach the metro trains that were not disrupted by the disastrous weather. Trams, on the other hand, worked in a limited capacity due to downpours.

Bad weather also affected air travel at Sabiha Gökçen airport. A passenger plane arriving from Tel Aviv was diverted to an airport in the western province of Çanakkale when it could not land at the airport due to heavy rainfall. Several flights were delayed at the airport.

Istanbul Mayor Ekrem İmamoğlu, who was criticized for going on holiday at times when extreme weather incidents hit the city, was at the Disaster Coordination Center (AKOM) this time, boasting of "minor problems despite heavy rainfall."

"Unfortunately, the impact of climate change may bring rainfall in the middle of summer," he told reporters. İmamoğlu stated that 5,890 personnel from the Istanbul Metropolitan Municipality (IBB) and 2,135 vehicles were at service of Istanbulites to address rain-related problems. He said a massive amount of precipitation hit parts of Istanbul, citing "90-100 kilograms of precipitation per square meter" in Çekmeköy and another 80 kilograms per square meter in Sarıyer.

He said "momentary" incidents led to floods on some roads but their response time to help people affected by the weather was 15 minutes at most. "We cleared the floodwaters and currently, the level of floodwaters is at a reasonable level," he said. He also warned that the rainfall may continue throughout the day and urged Istanbulites to avoid driving or going out.