The JMA and JTWC still treated the storm as Olga as it entered the area of responsibility of the Philippines, in which the state weather bureau tracked the system as "Didang".

Upon inland, Olga subsequently weakened to a tropical storm as it slowed down over Central Luzon before finally exiting through the South China Sea on May 24.

There, it slightly strengthened to a tropical storm as it neared land again, this time over Northern Luzon before becoming absorbed by a subtropical disturbance to the south of Okinawa on May 28, in which the JTWC last monitored the system one day prior.

As a slow-moving system, Olga caused copious amounts of rainfall over the Philippines, with one area recording 50 inches of rain (1,300 mm), becoming one of the wettest tropical cyclones the island nation had ever endured.

150 km/h (95 mph) winds were also recorded at Iba, where sets for the movie Apocalypse Now were destroyed and its staff were forced to shelter in hotels and houses.

For some of its early life, this precursor circulation generally moved southwestward, although the Japan Meteorological Agency (JMA) first tracked its predecessor at 18:00 UTC of May 11 as a 1,004 hectopascals (29.6 inHg) system.

Six hours later, the disturbance made a west-northwest movement as being guided by the southern periphery of a subtropical ridge in the Pacific before the agency upgraded the system to a tropical storm on the next day in the afternoon.

The new circulation interacted with the strengthening system, before the original center dissipated and its remaining convection had been absorbed by the second feature while moving west-northwest.

At this time, Olga was now tracked by the Manila Weather Bureau (now the PAGASA) as it entered the Philippine Area of Responsibility (PAR) and assigned it the local name “Didang”.

[1][2][3] Olga subsequently entered an area of unfavorable wind shear caused by a 200 mb ridge inclined over the Southeast Asia and despite this, it slowly intensified while nearing the mainland Philippines.

At approximately 00:00 UTC of the next day, Olga made landfall on the province of Aurora with an estimated maximum sustained winds of 185 km/h (115 mph) and a barometric pressure of 940 hectopascals (28 inHg), making at a Category 3 typhoon.

It subsequently reintensified slightly before turning to the northeast, this time sparing Northern Luzon a direct hit again from the system as it passed through Batanes as it inclined north-northeast.

The system was last tracked by the weather bureau of the Philippines on May 26 before the final advisory was issued by the JTWC at 06:00 UTC of that day while located to the east of Hengchun in Formosa (now Taiwan).

The agency also noted that the remnants of Olga were absorbed into a subtropical disturbance on May 27 to the south of Okinawa, although the JMA continued to track the system until they dropped monitoring it on 12:00 UTC of May 31 near the International Date Line.

[1] The summary of the events after the storm wrecked through the country are summarized by date[nb 1] as follows: On May 19, before moving inland, Olga's rainbands caused heavy rains, leading to flash floods in metropolitan Manila.

As a response to this, the Philippine President at that time, Ferdinand Marcos lifted the regular 1-4 am martial law curfew to let thousands of stranded passengers go home without any fines.

At least 10,000 individuals forced to flee their homes in Quezon City due to over 16.1 inches (410 mm) of rain, with the said amount being confirmed by Roman L. Kintinar, the chief of the Manila Weather Bureau.

Floods came as workers in the city were reportedly finishing 25 inundation-control projects that were set up at that time.The Philippine Red Cross appealed help to USAID and local residents to the area for food supplies for the victims of the storm.

Marcos said in news reports from the Philippines that a PAF C-47 aircraft poured sodium chloride onto Olga to contain the record rainfall it brought onto the country's capital, but it did still dropped record-heavy downpour.

A rescue official also informed the media in the country that bad weather also prevented the dispatch of planes to check the Seng Hong, a Panamanian-registered freighter that was reported to be run aground near Mamburao Bay, located to the south of the capital.

In additional, communications from Manila to Zamboanga in Mindanao, where an aircraft hijacking happened on May 21 there and ended on May 24 were disrupted due to broken transmission lines in the former.

The AFP ordered the evacuation of 50,000 persons living near the foot of the said basin while a flood control station, located 40 miles to the north of Manila recorded rising two-feet floodwaters.

The country's defense home center in Pampanga appealed for US water-resistant vehicles from Clark Air Base and helicopters for rescuing and evacuating stranded residents.

[23][24][25][26] 40-80% of the sets at Iba, Zambales from the production of the 1979 American epic psychological war film Apocalypse Now were also wrecked due to strong winds from Olga.

Despite these, businesses in Manila were opened after five days of closure while several thousands of passenger ferries and vessels were still in shelters and stranded in Mindoro Island, in which most of them were bound to the capital.

In one town north of Manila, Calumpit, the water is still up to the roof of the school” On May 29, at least 1,000 persons or over 100 vehicles were trapped in Dalton Pass in the Caraballo Mountains; military helicopters were trying to reach the area but were unsuccessful due to bad weather.

The Philippine Red Cross also noted that Japan, Canada, Finland, Great Britain, Australia, and New Zealand had responded to the appeal they made for help, either receiving cash or relief goods as a donation.

In addition, the President also announced the cancellation of a grand parade and traditional reception that was supposed to be held on June 12, the country's independence day due to the reason that “there’s nothing to be happy about”.

[33][34] The death toll further rose to 203 on May 31, according to the latest tally of the PRC at that day, including 5 individuals whose died of starvation due to them being trapped in a mountain pass isolated by landslides.

Sixteen choppers from the Philippine and U.S. Navy rescued all the 1,000 people whose isolated over the Dalton Pass; several motorists are still stranded over the Cagayan Valley highway stretch due to destroyed and faded roads.