Typhoon Shanshan, known in the Philippines as Typhoon Luis, was a strong typhoon that affected parts of East Asia in late September 2006. The 13th named storm of the 2006 Pacific typhoon season, Typhoon Shanshan was also the seventh typhoon of the year operationally recognised by the Japan Meteorological Agency. In post-operational analysis Shanshan became the eighth typhoon of the year when Typhoon Maria was added to the list. The Joint Typhoon Warning Center considered Shanshan the 13th tropical storm and eighth typhoon of the season, a Category 4-equivalent typhoon in terms of 1-minute average wind speed. The name Shanshan was submitted to the naming list by Hong Kong and is a girls' given name.

Shanshan wreaked havoc in Japan, with reports that it caused a tornado which derailed a train. It made landfall first in the Yaeyama Islands, where it caused heavy rains, and later in Kyūshū. The outer bands of Shanshan also affected South Korea. Shanshan also knocked power out to thousands of homes in the two countries, and killed at least eleven people. Damage amounted to $2.5 billion (2006 USD), making Shanshan the sixth costliest disaster worldwide in 2006.

Typhoon Shanshan (2006)

Meteorological history

On September 9, 2006, the Japan Meteorological Agency identified a tropical depression with 25-knot 10-minute average sustained winds about 500 kilometres (300 mi) north-northeast of Yap, near latitude 14.0°N longitude 139.0°E. Later that day, the Hong Kong Observatory (HKO) picked up on the tropical depression and started issuing track forecasts for the system.

Typhoon Shanshan (2006)

As the system continued to move northwestward, the Joint Typhoon Warning Center initiated advisories on Tropical Depression 14W on the morning of September 10. Later that day, the tropical depression moved into the PAGASA Area of Responsibility, and was named Luis. As the system continued to strengthen, the JMA upgraded the depression to a storm at 1200 UTC and named it Shanshan, a girls' given name submitted by Hong Kong. The HKO did the same at the same time, upgrading the depression to a storm.

Typhoon Shanshan (2006)

The storm quickly strengthened, being upgraded twice by the JMA on September 11, at 0600 UTC to a severe tropical storm and at 1800 UTC to a typhoon, becoming the seventh official typhoon of the season. It then took on a more west-northwesterly track, weakening while undergoing an eyewall replacement cycle on September 14. However, it restrengthened, reaching its maximum intensity of from the JMA and from the JTWC before passing Iriomote on September 15. Originally expected by the JTWC to pass to the east of Okinawa Island, a subtropical high-pressure ridge south of the main Japanese islands forced the storm to take a more westward track, pushing it towards Taiwan. Shortly later, Shanshan passed directly over Iriomote.

PAGASA issued their final advisory later on September 16. Peak intensity for Typhoon Luis as reported by PAGASA while it was in their area of responsibility was only . Shanshan made landfall on September 17 on the island of Kyūshū. The HKO issued their final track forecast on the weakening typhoon later that day as it passed out of their area of responsibility, with the peak intensity while within HKO's area of responsibility set at . The JTWC declared the system extratropical shortly after.

The JMA downgraded the typhoon to a severe tropical storm at 0000 UTC September 18. Just before crossing the island of Hokkaidō, according to the JMA's best-track graphic, Severe Tropical Storm Shanshan became extratropical twelve hours later. The extratropical storm was tracked by the JMA in their high seas marine warnings until September 22.

Preparations

In anticipation of Typhoon Shanshan, the Taiwan Central Weather Bureau issued a marine warning for all ships in the areas around the north and the east coasts of the island and in the Bashi Channel. Tourists were also asked to avoid the areas due to fears over large waves. The Zhejiang provincial government in the People's Republic of China also asked all fishermen to return to port and ordered local authorities to help with evacuations of people from areas threatened by the typhoon.