Environmental conditions became more conducive for intensification, which allowed 15W to intensify into a tropical storm and attained the name Kalmaegi.

Around 17:00 PHT (09:00 UTC) on September 14, the eye of Kalmaegi made landfall in the coastal town of Divilacan, Isabela, bringing gusty winds and heavy rains in the area.

Shortly after landfall, Kalmaegi was downgraded to a severe tropical storm while JTWC maintained a Category-1 typhoon.

On September 15, Kalmaegi left the responsibility as it headed for Southern China where it intensified back to a typhoon.

Kalmaegi rapidly weakened to a large tropical storm as it continued to move in a westward direction.

Kalmaegi made landfall over Cagayan early the next day, as it start to interact with land and weakened to a tropical storm.

[6] Kalmaegi rapidly weakened to a large tropical storm as it continued to move in a westward direction.

[8] PAGASA had also warned residents in regions of Luzon about landslides, thunderstorms and flash floods from the effects of Luis.

[9] As the storm was exiting the country, PAGASA reported that the province of Pangasinan was under the "state of calamity" due to flash floods, especially towns in Calasiao, Santa Barbara and even as far as Urdaneta.

[16] Later that day, the storm hit Hong Kong, disrupting flights and forcing the stock market to close, as well as causing 29 injuries.