The sea holds a certain magic, its endless horizon, the gentle sound of the waves, and that unmistakable sense of freedom. Whether you’re swimming, floating, or simply splashing about in the shallows, for many, the sea is the very essence of carefree moments.
Rainy Season in Thailand: When the sea reveals its wild side
Between May and October, it’s the rainy season in Thailand – and that means not just more frequent downpours, but also a noticeably rougher sea. Especially along the west coast, in places like Phuket or Khao Lak, the usually calm and inviting waters can quickly turn into a powerful, churning sea. Tall waves roll onto the beach, often at seemingly harmless intervals – but beneath the surface, hidden currents and dangerous forces are at play.
During this time, strong undercurrents and rip tides are particularly common and they can catch out even the most experienced swimmers. Many people underestimate the power of the water, especially when it doesn’t look particularly dangerous at first glance.
But anyone who’s ever been caught in a rip current knows: The sea during the rainy season is anything but predictable – and certainly not to be underestimated.
The red flag means: Stay out of the water
On a sunny day at the beach, most people are thinking about relaxing, having a bit of fun, and cooling off in the sea. And in Phuket, that stunning turquoise water is hard to resist – even when the waves are up.
But right here lies a danger that’s often underestimated: when a red flag’s flying on the beach, it’s not just a friendly heads-up – it’s a serious warning that could mean the difference between life and death.
The Invisible Threat: Undercurrents
Many tourists believe that with a bit of swimming experience, they can handle rough seas. What they don’t see – and often realise too late – are the strong underwater currents, known as rip currents, which can sweep even experienced swimmers away. These currents often form right at popular swimming spots and are difficult to spot with the naked eye.
A rip current is a strong, narrow flow of water that pulls directly from the shore out to the open sea. It forms when water pushed onto the beach by waves rushes back out to sea. This water gathers into a tight “channel” and flows seawards at high speed.
The danger lies in the fact that rip currents are often not immediately visible, and anyone caught in one is quickly pulled away from the shore. Many panic and try to swim against the current – which is exhausting and can often have fatal consequences.
The right approach: Don’t swim against the current, but swim sideways – parallel to the shore – until you’re out of the flow.
Phuket: Dream beaches with a deadly risk
Phuket is famous for its stunning beaches like Patong, Karon, and Kata Beach. But especially during the rainy season – from May to October – there are unfortunately fatal swimming accidents here, often because visitors ignore the red flag or underestimate the sea. Every year, people lose their lives after feeling safe or simply not taking the warnings seriously.
Trust the lifeguards – they’re your guardian angels
Thailand’s lifeguards are well trained and know the local waters inside out. They put up the flags for a reason. Even when the red flag’s flying, there’s often a fenced-off area where you can swim safely under their watch during certain conditions. It’s best to stick to that spot – that way, if anything happens, help is never far away.
Take care getting into the water – that’s true for Thai women and their partners alike
Many Thai women often can’t swim. Still, some let their Farang partners lead them by the hand into the sea – out of trust and to enjoy the experience together.
But that’s exactly where the danger lies: If one of them gets caught by the current, suddenly two people are in serious trouble. Please don’t do this!
Why people still go into the water anyway
- Overconfidence (“I’m a strong swimmer”)
- Not knowing what the red flag means
- Peer pressure (“Everyone else is going in”)
- A sudden urge to cool off on a hot day—without checking the flag first
A simple request for everyone who holds the sea dear
You’re not being cowardly by staying out of the water when the red flag’s up – you’re being smart. You’re protecting your life and the lives of those you love.
Drowning Statistics in Thailand
Drowning remains a significant public health concern in Thailand, with alarming statistics highlighting the risks, particularly during the monsoon season.
National Overview (2014–2023):
- A total of 36,503 drowning deaths were reported, averaging over 10 deaths per day
- Children under 15 accounted for 6,693 fatalities, making drowning the leading cause of death in this age group
Recent Trends and Incidents:
- In April 2025, an average of 327 drowning deaths occurred, with the Songkran festival (April 13–15) witnessing a 1.5 times increase, averaging nearly 15 deaths per day
- Adults aged 45–59 were the most affected, followed by children under 15
Source: https://www.nationthailand.com/health-wellness/40048657
Phuket-Specific Data:
- In 2023, 12 drownings were reported between July 28 and August 3, including incidents at Freedom Beach, Karon Beach, and Surin Beach
- In June 2025, a Kazakhstani tourist drowned at Kata Beach, and a Russian tourist died at Surin Beach, both incidents occurring despite red flag warnings
Contributing Factors:
- Underestimation of water conditions, especially during the monsoon season.
- Ignoring red flag warnings, leading to tragic accidents.
- Lack of swimming skills and water safety awareness among tourists
Dangerous Beaches in Thailand – Especially During the Rainy Season
Besides Phuket, there are several other spots where swimming in the sea under the wrong conditions can be life-threatening:
- Khao Lak (Phang Nga): Shallow beaches with strong currents during rough seas. Rip currents cause fatal accidents from time to time
- Kata and Karon Beach (Phuket): Popular with surfers in the rainy season, but the waves and currents are not safe for swimming
- Nai Harn Beach (Phuket): Known for strong rip tides. Red flags are displayed here too – please take them seriously!
- Surin Beach and Freedom Beach (Phuket): Less supervised, with no or only occasional lifeguards on duty
- Ao Nang (Krabi): Beautiful, but once the weather shifts, dangerous waves can form quickly
- Chaweng Beach (Koh Samui): Also experiences deadly currents during the monsoon season
In Summary
The smartest thing is to avoid putting yourself in a life-threatening situation in the first place. Even if you’re a strong swimmer, never underestimate the sea. Currents can be far more powerful than you imagine – and out in open water, neither experience nor fitness will help once panic and exhaustion set in.
A beautiful day at the beach can turn into a tragedy simply by ignoring a small warning. Please don’t just watch the waves – keep an eye on the flag too. And if it’s red, stay on land or swim only within the marked safe zones.
I’ve seen firsthand just how serious the danger can be: at a beach in Phuket, a young, athletic man – strong and clearly fit – was pulled lifeless from the water. It was a shock.
Just a few days later, I saw another man in a hospital who had also been swept away by the current. He was in a coma for 14 days. By some miracle, he woke up and survived without lasting damage. It could so easily have ended differently.