Olga developed as a tropical depression about 550 km northwest of Yap on 29th July. It adopted a north-northwestward course and intensified gradually into a typhoon on the next days while heading towards Okinawa. The estimated maximum wind speeds (140 km/h) were reached on the 1st August (25.4N 128.8E at 06Z) and 2nd August (31.4N 126.1E at 18Z). On the 3rd at 00Z, Olga turned to north-northeast and inland over Korea (37.4N 126.5E) on the 3rd at 12Z with wind speeds of 105 km/h.

Meteorologists say the flooding is the worst in Asia in 30 years. Authorities across Asia estimated a total of 949 dead from flooding, mostly in China, where the Civil Affairs Ministry said 725 have died and 5.5 million people in 23 provinces have been evacuated since the flood season began in June.

Four days of torrential rains in the central Philippines have left 92 dead. In the Philippine capital, Manila, heavy rains unleashed a massive landslide that swallowed an entire hillside community. The landslide buried 25 houses and damaged 378 others including 31 reported dead. Rescuers continued to search for another 33 missing people, holding out some hope that survivors may be holed up in one house.

In Vietnam, 24 people have died and 25 others are still missing after downpours flooded parts of central provinces. Vietnam's Binh Thuan province was reeling from 550 mm of rain that swamped large areas of land and caused heavy losses. The flooding, the worst in the region in nearly 50 years, left more than 5,000 people homeless.

In South Korea, 43 were reported dead and 21 missing from strong rains along the border with North Korea. International Red Cross officials said at least 42 people were killed and 94 others badly injured in North Korea, and warned of worsening food shortages.

The total rainfall in the peninsula has been between 48 and 85 cm.

In Thailand, five people died and about 1,000 people were homeless after five days of flash floods engulfed the low-lying coastal province of Chanthaburi, 210 kilometers southeast of Bangkok. Authorities estimated that some 90,000 people were affected by floods. Three inmates were evacuated from a prison when the ground floor was flooded.

Rains damaged 16,000 hectares of fruit orchards; and Cambodian officials said four children died in a flash flood.

This image shows data from the scatterometer instrument coloured in red, green or blue according to which of the three antennas of the instrument provided the measurements. The image shows a representation of Typhoon Olga on the 2nd of August 1999 at 14:14 UTC based on measurements of the Wind Scatterometer instrument.

GMS image of Olga taken on the 2nd of August 1999 at 08:32 UTC.