A tropical depression spotted outside the Philippine area of responsibility (PAR) has intensified into a tropical storm and is forecast to reach typhoon intensity by Saturday evening or Sunday morning, weather bureau PAGASA said.

As of 4 a.m., Tropical Storm Khanun was estimated based on all available data at 1,315 km East of Eastern Visayas and moving west southwestward at 15 kph.

Packing 65 kph winds and gusts of up to 80 kph, the tropical storm is forecast to continuously intensify within the next 5 days.

"It is forecast to become a typhoon tomorrow late evening or on Sunday early morning and reach its peak intensity by late Monday or early Tuesday," PAGASA said.

Khanun is forecast to enter the PAR region between Saturday evening and Sunday morning. Once inside the PAR, the domestic name Falcon will be assigned to this tropical cyclone, according to the weather bureau.

The bureau said hoisting of wind signal over any portion of the country due to Khanun is unlikely. However, the storm may enhance the southwest monsoon, which will trigger occasional or monsoon rains over the western portions of Luzon and Visayas beginning Saturday or Sunday.

Watch more News on iWantTFC