The Philippine Atmospheric, Geophysical and Astronomical Services Administration said the typhoon was located some 712 km east of Hinatuan city, in Surigao del Sur province, packing winds of up to 250 km per hour (kph), reports Xinhua.
In Cebu province, class suspension applies to "all levels in public and private schools" from Nov 7 to 8, provincial Governor Hilario Davide III said.
Surigao del Sur's Governor Johnny Pimentel said "we're experiencing heavy rains now, but no winds yet", adding that he has already ordered an evacuation of all flood-prone areas in his province, which is under public storm signal number 1 (winds of up to 55 kph) and 2 (55-65 kph).
"We've been already prepared since Wednesday," Pimentel said.
Governors in Compostela Valley and Davao del Norte also asked soldiers and police to help disaster and rescue teams for possible massive flooding to be caused by Typhoon Haiyan. These areas were heavily devastated by Typhoon Bopha last year.
The Philippine coast guard said all sea travel was already suspended in Bislig city, another Surigao del Sur area expected to be directly affected by the storm.
Seven areas in Visayas region in central Philippines and in northern Mindanao are under signal number 2, while 30 other areas across the archipelago are under signal number 1.
The most powerful storm in the Philippines this year is expected to dump heavy to intense rainfall within its 600-km cloud diameter, and the state weather bureau has advised the public to be on alert.
The Philippines gets an average of 22 storms every year, being astride the so-called Typhoon Belt, between the Pacific Ocean and the South China Sea. Haiyan is the 24th storm of 2013.