Storm surge in the South Pacific: A coastal area pushed to its limits
Among blue-water sailors, Wellington is regarded as a well-established stopover off the beaten track of the classic tropical barefoot route. Reliable weather data, well-sheltered bays and a well-developed maritime infrastructure generally make the region a comparatively safe port of call.
This made the situation at the start of this week all the more remarkable: the New Zealand Meteorological Service forecast for the south coast MetService significant wave heights of 9 to 11 metres.
The authorities acted promptly and declared a local state of emergency for the particularly vulnerable coastal suburbs of Ōwhiro Bay, Island Bay, Houghton Bay and Breaker Bay (local state of emergency). Coastal roads were closed and residents in at-risk areas were evacuated. Wind gusts of up to 130 km/h were recorded at Wellington Airport, and several regional flights were cancelled.
At the wave observation station Baring Head At the entrance to Wellington Harbour, sensors recorded wave heights of up to 11.4 metres. The fact that no serious structural damage occurred was mainly due to the favourable timing: the main force of the swell struck the coast as the tide was ebbing. Nevertheless, the city council considered the extensive protective measures to be justified, citing the significant coastal damage suffered in the winters of 2020 and 2021.
What recreational boaters can learn from this
The Wellington case clearly shows that it is not just wind strength that determines the safety of a sailing area. Several important lessons can be drawn from this for planning a sailing trip.
1. The safe haven may become inaccessible in extreme weather
Understandably, many skippers focus on reaching a sheltered mooring as quickly as possible. However, extreme weather events show that the infrastructure around the harbour can also fail. Flooded jetties, flotsam, blocked access roads or official closures can mean that, whilst a harbour remains safe from a nautical perspective, the crew can no longer get ashore or supply routes are cut off.
Practical tip: When planning a trip, it is important to consider alternative ports, access to land and supply options. Knowing several alternative options gives you valuable flexibility.
2. When the wave arrives before the storm
During large-scale weather systems, the danger is often underestimated as long as local wind speeds still appear relatively moderate. However, swell from far away can carry enormous amounts of energy over long distances. When this swell hits coasts, harbours or marinas, it can cause strong movements in the harbour basin. Mooring lines, cleats, dolphins and jetties are sometimes subjected to greater stress than during local gale-force winds.
Practical tip: If long-period swells are forecast, mooring lines should be checked, additional lines prepared and sufficiently robust shock absorbers fitted. Even marinas that appear to be well sheltered can be subjected to considerable stress under certain swell conditions.
3. Wave forecasts deserve the same attention as wind charts
Many recreational boaters base their decisions on wind strength and direction. However, incidents such as the one off Wellington show that wave height, wave period and the direction of the swell can be just as crucial. The good news is that authorities worldwide are increasingly taking a precautionary approach to extreme weather conditions. Closures are now often implemented much earlier than was customary just a few years ago.
Practical tip: Significant wave height, swell direction and official warnings should be given just as much consideration when planning a trip as traditional wind forecasts. If in doubt, it is safer to interpret the forecasts on the conservative side.
4. Extreme weather does not only affect the coast
The consequences of extreme weather conditions have long extended far beyond wind and waves. Disruptions to the power supply, transport infrastructure or communication networks can make the situation even more difficult for crews. For cruising sailors, this means that risks must be assessed holistically, not just from a meteorological perspective.
Practical tip: Before entering an affected area, you should check the latest information on port operations, road access, petrol stations and supply facilities just as carefully as you would check the weather data.
Pacific Year 2026: When extreme weather hits the coast
Wellington is not alone in this. Meanwhile, on the other side of the ocean, Tropical Storm ‘Cristina’ is causing disruption in the eastern Pacific. The National Hurricane Centre The National Hurricane Centre (NHC) issued warnings for the coasts of El Salvador and Guatemala. Meteorologists reported heavy rainfall there, with rainfall totals of 150 to 250 litres per square metre.
The flooding caused significant damage to the affected coastal areas of Guatemala Waste from civilisation and driftwood washed up on the shore after being carried out to sea via the rivers. This creates additional hazards for recreational boating in the form of half-submerged tree trunks, floating obstacles and blocked cooling or filter systems.
This incident highlights the fact that the risks associated with extreme weather do not stem solely from the weather conditions themselves. When preparing for a trip, one should also take into account potential consequential damage to infrastructure and waterways.
El Niño and global storm patterns
The fact that the Pacific appears to be particularly active this year is in line with the seasonal forecasts issued by the US climate agency NOAA. A moderate to strong El Niño alters the global distribution of tropical and extratropical weather systems.
Statistically, El Niño in the Atlantic is often associated with lower hurricane activity, whilst activity in the Pacific increases – particularly in the north-western Pacific, where the typhoon season takes place.
- Read more on the meteorological relationships in our comprehensive overview article “El Niño expected: a calmer Atlantic, an extremely stormy Pacific”
But patterns are changing in European regions too. A recent study by the University of Gothenburg in Journal of Geophysical Research (JGR) concludes that spring and autumn storms over the northern oceans – including the North Sea and the Baltic Sea – are increasing in both intensity and duration.
One example of this was Storm “Dave”, which swept across the Danish North Sea coast over Easter 2026 with peak gusts of 145 km/h and waves of up to 11 metres.
- Read more: You can find the full report in the article “Research: Spring storms over the North Atlantic are on the rise – study from Gothenburg
Conclusion: Prevention is better than cure
The 11-metre waves off Wellington are geographically far away. However, the lessons they teach apply everywhere. Extreme weather conditions repeatedly demonstrate that familiar waters can present entirely new risks within a matter of hours.
Those who pay equal attention to weather and wave forecasts, take official warnings seriously and plan safe alternatives well in advance significantly improve the safety of the crew and the vessel.
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How do you deal with these changes when planning your own sailing trips? Have you adapted your approach in recent years? Please feel free to share your experiences and strategies in the comments.
Antonia von Lamezan
Volontärin
