This is a really very seldom occurrence. Davao City is placed under a storm signal. DOST-PAGASA has placed the city together with other Mindanao provinces like Cotabato, Zamboanga Provinces and Lanao Provinces under Signal #1. Tropical Storm SENDONG is still at the sea and will make a landfall at Hinatuan, Surigao del Sur.
Here's the latest picture from DOST - PAGASA weather services
For more updates, you can visit the website of PAGASA. Stay safe and dry people!