Expert: ‘Unpredictable’ Typhoon In-fa may bring catastrophic rainfall

TAIPEI (The China Post) — The Central Weather Bureau (CWB, 中央氣象局) reported Monday that typhoon no. 6 “In-fa” (烟花) is heading west-northwest from its center at 1,050 kilometers to the seas east to Taiwan, which may bring about torrential rainfall.

Moving at a speed of 6 to 9 kilometers per hour, In-fa is caught within a monsoon depression, which makes it susceptible to the influence of the pacific high, depression circulations as well as any resulting tropical systems.

This means that there is still a lot of unpredictability in the direction that the typhoon will move in.

In addition, a tropical depression has developed at 8 p.m. Sunday and is set to linger around the seas surrounding Guangdong province.

The area outlined in red on the right shows the possible region of In-fa’s movement. (Photo courtesy of the Central Weather Bureau)

Meteorological expert Wu Der-rong (吳德榮) wrote in a column for SET News (三立新聞) that “In-fa is gaining momentum and may climb to moderate intensity in the future, adding that it is generally headed towards Taiwan’s northern seas.

The area outlined in red shows the uncertainty in In-fa’s potential trail, Wu pointed out.

“Will it hit Taiwan? That remains to be seen,” he said.

If typhoon In-fa approaches the tropical depression while still being caught in a monsoon depression, it may cause a Fujiwara effect (藤原效應), which might result in the formation of a bigger typhoon.

With so many uncertain factors, even the most advanced simulation systems won’t be able to simulate In-fa’s activities with complete accuracy, Wu added.

“Trying to predict when the typhoon alert warning will be announced and how big of a storm is expected on a particular day while ignoring the uncertainties of In-fa’s potential movement is unscientific,” remarked Wu.

According to Wu’s analysis, In-fa’s peripheral circulation may result in significant rainfall Tuesday and Wednesday in northern Taiwan, while central and southern Taiwan may expect occasional showers or thunderstorms in the afternoon.

While In-fa is set to close in on Thursday and Friday, rainfall and wind levels of each region in Taiwan may defer according to the typhoon’s relative position.

The days between Saturday and next Wednesday (July 28) will see the monsoon depression circulating around East Asia, possibly bringing with it tropical depressions, typhoons as well as the southwest monsoon.

This could potentially result in heavy rainfall with extreme weather conditions, a recipe for catastrophic weather.