Typhoon City

"What we are seeing are typhoons with greater intensities, slower movement, and more prolonged impacts."

Are we experiencing more typhoons than usual, and are they more powerful? It certainly seems like it. And is climate change a factor, or is something more nuanced going on? 

Hong Kong has seen the highest number of typhoons in a year since records began in 1917, according to the Hong Kong Observatory. By mid-September 2025, Hong Kong had already raised typhoon warning signals 12 times, a figure that could increase. Of course, not all these typhoons made a direct hit; in fact, far from it. 

Typically, we’d see 10 typhoons each year, although only one or two would warrant the highest signals. The Hong Kong typhoon season normally begins in May and lasts until November. Although it might seem like there are more typhoons in Hong Kong recently, it’s not that the overall number has increased; instead, a combination of factors makes their effects feel more severe.

What we are currently experiencing are typhoons with greater intensities, slower movement, and more prolonged impacts. In addition, the impact of larger storm surges brought about by warmer ocean temperatures increases unpredictability, requiring forecasters to work harder.

Furthermore, a government that is more attentive to the potential effects of the typhoon has emerged. Consequently, there is an increase in publicity and precautionary messages, raising awareness of the dangers. This improved stance by the government is welcome, especially considering the swift recovery efforts and well-coordinated responses we have observed. 

The truth is, Hong Kong lies in 'Typhoon Alley.' We border the South China Sea, a warm body of water; typhoons are driven by warm ocean water above 26.5°C or 80°f. The Northwest Pacific Basin, located south-west of us, is the world's most active tropical cyclone basin, producing about one-third of all such storms. Hong Kong is directly in the usual path of many storms that form in this basin, especially those heading west or northwest towards the Asian mainland.

Although the total number of typhoons hitting Hong Kong may not have risen significantly, we are noticing increased intensities. The science behind typhoons is well understood: warmer sea surface temperatures provide more energy for these storms.

This leads to storms that form having a greater potential to become stronger and undergo rapid intensification more often. A stronger typhoon, even if it does not make a direct hit, can cause substantially more damage.

Furthermore, a warmer atmosphere holds more moisture. This causes typhoons to bring significantly more rainfall, heightening the risk of severe flooding and landslides in Hong Kong's steep terrain.

Meanwhile, modelling of typhoon tracks suggests that climate change may be causing slight shifts in their paths, potentially increasing landfalls in Southern China, including the Pearl River Delta, where Hong Kong is located.

Nevertheless, attributing all the blame to climate change might be mistaken. We could be observing a shift within a much longer cycle of typhoon behaviour. Typhoon activity follows a multi-decade pattern influenced by natural climate variations, such as the Pacific Decadal Oscillation (PDO). From the 1990s to the early 2010s, Hong Kong saw a relative period of fewer direct hits from very intense typhoons.

Since around 2017, the region has entered a more active phase. This is part of a natural cycle, but scientists suggest it's now amplified by climate change, making the storms during this active period even more powerful. This contrast gives the impression that many typhoons are occurring now, compared to the quieter times many residents remember.

Furthermore, increased urbanisation and land reclamation have heightened our vulnerability. Hong Kong’s unique cityscape, with its forest of skyscrapers, is more susceptible to high winds funnelled between buildings. For public safety, the government adopts a cautious approach by closing the city earlier. As a result, each typhoon becomes a major economic and logistical event, attracting extensive international media coverage.

In the future, as I mentioned in another blog, the government will need to strengthen measures to reduce the impact of tidal surges. Similarly, building regulations and zoning laws for construction will need updating. 

To sum up: Hong Kong isn't necessarily experiencing more frequent typhoons. However, it is encountering more intense and destructive storms because of its location, a return to an active natural cycle, and the potential amplifying effects of climate change.