Northern, western and eastern Samar; and Dinagat and Siargao islands were placed under Signal No. 1, or winds with 45-60 kilometers per hour, the Philippine Atmospheric Geophysical and Astronomical Services Administration said.
Residents under these areas were alerted against flashfloods and landslides.
The tropical depression will enhance the southwest monsoon, which will bring moderate to occasionally heavy rains and thunderstorms over the Visayas and Mindanao.
Gorio, which packed maximum sustained winds of 45 kilometers per hour, remained almost stationary as it slightly changed its direction.
It was last located 500 kilometers east of Surigao City, and was moving northwest at 7kph.
Gorio was forecast 360 km east of Guiuan, Eastern Samar, by Saturday morning; 340 km east of Legazpi City in Bicol by Sunday morning; and 340 km east of Baler, Aurora, by Monday morning, Pagasa said.
Eastern and Central Visayas and Mindanao will experience cloudy skies with light to moderate rainshowers and thunderstorms, while Metro Manila and the rest of the country will be partly cloudy to cloudy with isolated rainshowers or thunderstorms mostly in the afternoon or evening.
Moderate to strong winds blowing from the northeast to northwest will prevail over eastern Visayas and Mindanao with moderate to rough seas. Light to moderate winds coming from the east to southwest will prevail over central and northern Luzon and from the northeast to northwest over the rest of the country where the coastal waters along these areas will be slight to moderate, Pagasa said.