[4][5] Meanwhile, the Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert on the developing depression.

During the next day Sinlaku continued to intensify and reached its maximum 1 minute sustained winds of 125 knots which made it a Category 4 typhoon.

It stayed at this intensity until the next day when it started to weaken as it went through an eye wall replacement cycle.

Sinlaku then struggled to come out of its eye wall replacement cycle and as a result weakened into a Category 3 typhoon.

[15] Early on September 21 the JMA downgraded Sinlaku to an extra tropical low as it moved further away from Japan.

[16] On September 8 PAGASA started to issue Public Storm warnings on Typhoon Marce (Sinlaku).

Pagasa immediately hoisted Public Storm warning 1 over parts of Luzon including the Bicol, Isabela, Aurora & Cagayan Regions.

[21][22] On September 10 the Central Weather Bureau (CWB) issued warnings for heavy rain in north Taiwan.

[23] then on September 11 the CWB decided to issue sea warnings which meant that ships that were sailing within the Bashi Channel had to take extra precautions.

[46] A large section of a 2,000 ft bridge collapsed with five people on it after heavy rain caused supports to break.