Turkey: Adverse weather forecast across western regions through at least Aug. 11

Event

Thunderstorms and heavy rainfall are forecast across parts of western Turkey through at least Aug. 11. The thunderstorms will likely be accompanied by strong wind gusts, lightning, and possible hail storms. Disruptions due to flooding are ongoing in parts of Istanbul early Aug. 10 following heavy rainfall.

The Turkish State Meteorological Service has issued the following weather warnings across the affected area Aug. 10:

• Yellow thunderstorm warnings (the lowest level on a three-tier scale): Afyonkarahisar, Ankara, Burdur, Denizli, Eskisehir, Isparta, Istanbul, Kutuhya, Tekirdag, and Usak provinces.

The following warnings have also been issued for Aug. 11:

• Orange thunderstorm warnings (the middle level on a three-tier scale): Duzce, Istanbul, Kocaeli, Sakarya, and Zonguldak provinces.

• Yellow thunderstorm warnings: Bartin and Yalova provinces.

Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.

Flooding and associated traffic disruptions are ongoing in parts of Istanbul following heavy showers early Aug. 10. Streets and subways have been inundated as storm drainage systems were overwhelmed in some areas of the city, including Beylikduzu and Esenyurt. Further rainfall forecast over the coming hours and days could trigger additional flooding and associated disruptions across parts of Istanbul, as well as other parts of the affected area.

Hazardous Conditions
Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed stormwater drainage systems. Sites located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where heavy rainfall has saturated the soil.

Authorities could issue mandatory evacuation orders for flood-prone communities over the coming days. Disruptions to electricity and telecommunications services are possible where significant flooding or landslides impact utility networks.

Transport
Floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters.

Severe weather could also trigger flight delays and cancellations at airports in the affected regions. Flooding could block regional rail lines; freight and passenger train delays and cancellations are likely in areas that see heavy rainfall and potential track inundation.

Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, possible evacuations, and some employees' inability to reach work sites.

Advice

Monitor local media for weather-related updates and advisories. Confirm all transport reservations and business arrangements before traveling in the affected area. Seek updated information on road conditions before driving or routing shipments through areas where severe weather is forecast; plan for possible supply chain disruptions throughout the affected areas. Stay away from elevated streams, creeks, and other watercourses that are prone to flash flooding. Do not attempt to navigate flooded roadways. Exercise caution in elevated terrain due to the threat of landslides and mountainous regions where avalanches pose a threat. Charge battery-powered devices in the case of prolonged electricity outages.

Resources

Turkish State Meteorological Service