Why your flight is more likely to encounter turbulence or disruptions

SINGAPORE – Even after 18 years, Singaporean Glenn Koh still grips his seat whenever a flight encounters prolonged turbulence. The 43-year-old was travelling from London to Zurich with his wife in June 2008 when their plane was hit by severe turbulence. “The turbulence got worse throughout the flight and it came to the point where we felt the plane dip. I knew it was serious because we were lifted off our seats and feet for a few seconds,” says Mr Koh, who recently left his job as a director in the hospitality industry. “There were people screaming and I think that multiplied the fear. My instant reaction was to grab the seat and my wife’s hand, and then we started getting nervous.” The ordeal lasted around 20 minutes.

Only after landing did he learn that the aircraft had flown into one of the worst hailstorms Switzerland had experienced in recent history. Mr Koh, who graduated from Singapore Youth Flying Club in his younger days, says even his understanding of aviation could not shield him from the anxiety of the experience. He believes turbulence has become increasingly common and remains cautious when flying. Turbulence was the leading cause of accidents in the Asia-Pacific region from 2022 to 2024, according to the International Civil Aviation Organization’s Annual Safety Report 2025, which noted that “more adverse weather conditions brought about by climate changes” are expected to sustain the trend.

High-profile turbulence-related incidents such as the Singapore Airlines flight SQ321 from London to Singapore in May 2024, which left one passenger dead and many more injured, have also heightened public awareness of the risks. Experts say the issue is not that aviation has suddenly become unsafe, but that climate-related weather volatility is making flight operations more difficult and the passenger experience more unpredictable. “Climate change has made aviation risk more complex,” says Mr John Tan, lead professional officer teaching in the aviation management degree programme at the Singapore Institute of Technology. “The concern is not only stronger weather. It is greater volatility, shorter decision windows and wider disruption across the aviation network.” As global warming worsens, heatwaves can affect aircraft performance and runway operations, while stronger storms may force rerouting and reduce airport capacity. “The risk now extends beyond the aircraft in flight. It affects routing, fuel planning, crew rostering, cabin service, passenger connections and disruption recovery,” says Mr Tan. “Climate change raises the baseline level of uncertainty.

That matters because aviation safety depends on prediction, preparation and timely decision-making.” The issue with turbulence One major concern among researchers is the growing unpredictability of weather systems and “climate system tipping points”. These critical thresholds, when crossed, can trigger rapid and potentially irreversible shifts in climate patterns, says Professor Dale Barker, director of the Centre for Climate Research Singapore (CCRS). They include disruptions to ocean currents, accelerated polar ice melt and thawing Arctic permafrost. Turbulence itself can stem from several weather phenomena.

Clear-air turbulence – one of the most difficult forms to predict – often occurs at high altitudes without visible storm clouds and is linked to sudden wind changes around jet streams. “These wind changes are invisible and occur on a small scale, making them hard to detect and forecast accurately,” Prof Barker adds. Another phenomenon called convectively induced turbulence can develop around thunderstorms, including at some distances away from storm clouds. He says: “Thunderstorms, especially in the tropics, can form quickly, which adds to the difficulty in forecasting this type of turbulence.” A study published by the University of Reading in June 2023 found that the incidence of clear-air turbulence has increased significantly over the past four decades, consistent with the expected effects of climate change. When analysing an area over the North Atlantic, for instance, the study found that the strongest category of clear-air turbulence was 55 per cent more frequent in 2020 than in 1979. “Climate change has a direct impact on aviation.

Adverse weather events, such as lightning, thunderstorms and turbulence, disrupts flights and airport operations and are potential safety risks. These events are now more frequent than before,” says Mr Tan Kah Han, chief technology officer and senior director of the Next Generation Programme Office at the Civil Aviation Authority of Singapore. The number of flight diversions from Singapore Changi Airport due to adverse weather increased by nearly four times, from 15 in 2024 to 59 in 2025. Tackling unpredictability The growing impact of climate change is partly why CAAS has identified severe turbulence as a “major in-flight risk” in its National Aviation Safety Plan (2025 to 2027), according to Mr Tan.

Singapore is the first state in the world to do so. “Aviation today already uses advanced weather-monitoring and forecasting systems, including real-time data and predictive models. However, there are limitations to what technology can help us do,” he says. “For example, in parts of the world with convective weather like Singapore, weather can change very suddenly and vary across short distances. This makes precise forecasts and timely reactions difficult.” On May 19, the Singapore Transport Safety Investigation Bureau (TSIB) released the full investigation report for the SQ321 incident. It found that the aircraft’s weather radar may have failed to detect the weather that likely caused the severe turbulence.

The report also concluded that the turbulence was likely triggered by a rapidly developing cloud formation, though it remained unclear why the pilots were unable to observe the widespread clouds from the cockpit. As weather-related aviation risks grow more complex, Singapore has ramped up efforts to strengthen forecasting and operational resilience. In December 2025, CAAS and the National Environment Agency (NEA) established a national Aviation Meteorological Programme, which uses artificial intelligence (AI) and predictive tools to improve weather forecasting and help airports, airlines and air traffic controllers respond more effectively to disruptions. Projects under the programme include systems that forecast lightning risks and predict how convective weather and tailwinds may affect runway operations and air traffic flow.

Across both projects, AI’s role in prediction and translating data into actionable operational insights will allow decision makers to “move from reactive responses towards more proactive and efficient management of weather-related risks”, says Mr Patrick Ky, chief executive officer of the International Centre for Aviation Innovation (ICAI). ICAI works with CAAS and NEA on projects in the Aviation Meteorological Programme. “For passengers, this means safer journeys, more effective management of weather-related disruptions, and more reliable travel experiences over time,” he adds. Reality in the air In December 2018, senior art director Jamie Fong, 30, experienced turbulence so severe on a flight from New York to Singapore that she began typing a note into her mobile phone, fearing she might not survive the journey. Part of it read: “We got lifted from our seats twice and it was basically so bumpy that I would even think of writing this just in case I don’t make it.” While the incident has not deterred her from flying, she says it has awakened her to the reality about climate change’s increasingly significant impact on air travel. “I think turbulence has become a lot more common.

It is just one of those things that feels like it isn’t within my control. What can you do if a plane really goes down?” she says. The reality is that modern aircraft are engineered to withstand significant turbulence loads, but unbelted passengers, loose objects and service carts can become hazards during sudden turbulence events, says SIT’s Mr Tan. He adds that aviation remains “extremely safe”, but the industry cannot take climate change for granted. “Airlines are adapting (to climate risks), but not evenly.

Many still manage climate risk reactively: weather occurs, disruption follows, and recovery begins. That model is no longer enough. The stronger approach is to be proactive,” he says. “Climate change does not overturn aviation safety overnight. Airlines that adapt best will treat weather intelligence, cabin safety and operational resilience as core safety capabilities, not as afterthoughts during disruption.”