These dates conventionally delimit the period of each year when most tropical cyclones form in the northwestern Pacific Ocean.

The scope of this article is limited to the Pacific Ocean, north of the equator and west of the International Date Line.

[1][2] Anna originated from a vigorous tropical wave that moved west along the ITCZ during the days of March 16 and 17.

On March 18 an approaching cold front caused the wave to congeal into a tropical low pressure system while about 415 miles (668 km) to the east of Davao.

The Joint Typhoon Warning center (JTWC) best tracks[3] lists this system as 02W Carol formed east of the Philippines on June 17.

It then crossed the South China Sea en route to Hainan Island, where the system lost its identity.

Typhoon Jean made a direct hit over Manila during the Christmas holidays after organizing in the Philippine Sea to the southeast of Yap Island, moving west-northwest and accelerating as it made landfall in the border area of Albay and Camarines Sur.

The typhoon weakened into a tropical storm and recurved west of the Batanes group of islands and passed through the Bashi Channel south of Taiwan and continued north-eastward towards Miyakojima and the southern Japanese islands and eventually dissipated on 29 December.

Because Typhoon Jean battered Manila during the Yuletide season, there were some eyewitness reports of Christmas decorations being strewn around the city.