Severe thunderstorms swept across Istanbul on Saturday, triggering widespread flash flooding that submerged roads, stranded motorists and disrupted transportation across both the European and Asian sides of Türkiye's largest city.

The downpour arrived after the Turkish State Meteorological Service issued yellow-level warnings for locally intense thunderstorms.

Although the heaviest rain lasted less than an hour in many areas, it was enough to overwhelm drainage systems, flood homes and businesses, and paralyze traffic in several districts.

The European side bore the brunt of the storm, with Beşiktaş, Şişli, Kağıthane, Sultangazi, Fatih and Bakırköy among the hardest-hit districts. On the Asian side, heavy rain also affected Ümraniye, Çekmeköy, Kadıköy, Beykoz and Üsküdar.

Roads submerged

Major roads across the European side quickly disappeared beneath rising floodwaters as clogged drainage systems struggled to cope with the intense rainfall.

One of the worst-hit locations was the underpass at Zincirlikuyu, where rapidly rising water trapped several vehicles. Emergency crews responded by pumping water from the flooded roadway and helping stranded drivers reach safety.

In Şişli's 19 Mayıs neighborhood, shop owners removed manhole covers in an effort to drain water that had accumulated outside their businesses. Nearby, overflowing sewers in Halide Edip Adıvar neighborhood turned streets into hazardous waterways, making travel difficult for motorists.

Flooding also engulfed Mecidiyeköy Square, where vehicles crawled through water reaching wheel height while pedestrians struggled to cross submerged sidewalks.

In Fulya, a motorcyclist fought to save a motorcycle from rising floodwaters, while another motorcycle in Yayla neighborhood was swept several meters by the fast-moving current.

On Akar Street, torrents of water cascaded from a retaining wall onto the roadway, creating dangerous driving conditions. Flooding also forced authorities to reduce traffic in the Dolmabahçe Tunnel to a single lane until water levels receded.

Taxi driver rescued

One of the most dramatic rescues unfolded in Şişli's Halide Edip Adıvar neighborhood near Çiftecevizler Park.

A taxi became stranded after floodwaters rapidly surrounded the vehicle, with water rising to roughly door-handle level. The driver climbed out into chest-deep water before municipal emergency teams guided him to safety. Another commercial vehicle later helped pull the taxi from the flooded street.

Transit disrupted

Flooding also crippled transportation in Beşiktaş.

Three vehicles became trapped inside the underpass on Nispetiye Avenue after water levels rose sharply, forcing traffic to a standstill. Public buses operated by İETT were unable to pass through the flooded section, leading to lengthy traffic backups.

Elsewhere, floodwaters in Sultangazi rose above sidewalk level, leaving vehicle wheels submerged on numerous streets.

In Fatih, water pooled inside parts of the historic Grand Bazaar, prompting shopkeepers to work quickly to keep floodwater from entering their stores.

Overflowing sewers also spilled onto Piyalepaşa Boulevard in Beyoğlu, while in Bostan neighborhood, floodwaters carried a refrigerator into a parked vehicle, damaging the car.

Storm hits Asian side

The storm also affected several districts on the Asian side, although rainfall varied in intensity.

Residents in Çekmeköy attempted to clear blocked storm drains using sticks to restore water flow, while floodwater inundated the underground parking garage of a residential complex in Kadıköy.

Localized flooding was also reported in parts of Üsküdar, including the Sahaflar Çarşısı area and the Harem Coastal Road.

Emergency response

Istanbul Metropolitan Municipality Acting Mayor Nuri Aslan monitored the situation from the city's Disaster Coordination Center (AKOM).

He said some areas received between 40 and 57 kilograms of rainfall per square meter in roughly 45 minutes, an extraordinary volume that overwhelmed drainage systems in several neighborhoods.

Municipal authorities deployed 5,772 personnel and 2,035 vehicles to 267 response locations across the city, focusing on pumping floodwater, clearing blocked drains, rescuing stranded motorists and responding to reports of fallen trees and other storm-related emergencies.

Aslan said officials expected weather conditions and daily life to largely return to normal by early evening and urged residents to report flooding, fallen trees or other hazards through the municipality's 153 emergency hotline.

Flooding challenge

Saturday's storms once again exposed Istanbul's vulnerability to sudden summer downpours.

The city's dense urban landscape, low-lying neighborhoods and aging drainage infrastructure allow short bursts of intense rainfall to produce flash floods within minutes, particularly around underpasses and major transportation corridors.

Despite widespread property damage, flooded businesses and severe traffic disruption, authorities reported no major injuries or fatalities.

The Turkish State Meteorological Service warned that thunderstorms could continue to produce localized flash floods, lightning, hail and transportation disruptions, urging residents to avoid flood-prone areas and monitor official weather updates.