El Niño and Travel Health: What the 2026–27 Weather Pattern Could Mean for Travellers
El Niño is strengthening across the Pacific, with the US National Oceanic and Atmospheric Administration (NOAA) estimating a greater than 90% chance of a very strong El Niño during the Northern Hemisphere autumn and winter of 2026–27. The World Meteorological Organization and Pan American Health Organization are warning that the resulting weather patterns could create significant health and disruption risks across parts of the Americas in the months ahead. (Pan American Health Organization)
For travellers, the significance of El Niño is not simply hotter or wetter weather. Its effects can influence transport, accommodation, access to healthcare, air quality, water availability and the risk of some infectious diseases.
What is happening with El Niño?
El Niño occurs when unusually warm ocean temperatures develop in the central and eastern tropical Pacific, influencing atmospheric circulation and weather patterns across much larger areas. The current event has strengthened significantly. NOAA’s September assessment gave a greater than 90% probability of a very strong event during autumn and winter 2026–27, while also indicating a 75% chance of an historically strong event during October–December. (Climate Prediction Center)
The effects are not the same everywhere, however. El Niño can contribute to different weather patterns in different regions, and individual floods, droughts, wildfires or other events cannot automatically be attributed to the phenomenon.
How could El Niño affect travellers?
PAHO is already reporting drought, water shortages, wildfires and flooding across parts of the Americas. Its September situation report identified eight countries or territories with official emergency or alert declarations associated with El Niño-related hazards, alongside areas experiencing drought, wildfires and heavy rainfall. (Pan American Health Organization) For travellers, these conditions can have practical consequences.
Flooding and landslides can disrupt roads, railways and airports. Wildfires can affect air quality and visibility and may lead to local evacuations or transport disruption. Drought can put pressure on water supplies, while extreme heat can create additional health risks for people spending time outdoors. These effects can also occur away from the location where the original weather event is taking place, particularly when major transport routes or regional infrastructure are affected.
Extreme heat and travel health
Extreme heat is one of the clearest health concerns associated with the developing El Niño pattern. The World Meteorological Organization warns that as El Niño peaks towards the end of 2026, parts of the Southern Hemisphere, southern Africa, South America and Australia will enter their hottest months, potentially increasing the risks associated with heat, drought, wildfires and smoke. (World Meteorological Organization)
Travellers can be particularly exposed because sightseeing, outdoor activities and unfamiliar environments can make it harder to recognise how quickly heat stress is developing. People should take particular care with hydration, prolonged exposure to high temperatures and strenuous activity during periods of extreme heat.
Flooding, wildfires and air quality
Weather-related disruption can be just as important to a journey as the original weather event. PAHO is currently monitoring flooding and heavy rainfall in parts of the region, while wildfires are affecting air quality in several countries. In Brazil, for example, PAHO reports significant concerns around declining water levels in the Amazon Basin and deteriorating air quality associated with wildfires. (Pan American Health Organization)
Travellers should therefore monitor local weather and emergency information rather than relying solely on a general forecast for their destination. A journey can be affected even when conditions at the airport itself appear normal if roads, surrounding communities or onward transport routes have been disrupted.
Could El Niño affect disease risks?
Weather patterns can influence the conditions in which some infectious diseases spread. PAHO identifies vector-borne and water-borne diseases among the health risks that can be affected by El Niño. The organisation is already monitoring concerns including dengue, malaria and yellow fever in parts of the Americas, although the precise impact varies by location. (Pan American Health Organization) This does not mean that every destination experiencing unusual weather will experience an outbreak. It does mean that travellers should consider current health information alongside weather and security conditions when preparing for a trip.
What should travellers do?
Travellers do not need to treat El Niño itself as a reason to avoid international travel. The more useful approach is to understand how the developing weather pattern is affecting the specific destination and period of travel. Before departure, check current weather conditions, travel alerts and relevant health information. If travelling during periods of extreme heat, flooding or wildfire activity, consider how these conditions could affect your planned activities and transport arrangements.
It is also worth checking whether your destination has experienced recent disruption to healthcare services, water supplies or major transport routes. Conditions can change quickly, particularly during extreme-weather events, so travellers should continue monitoring local information after arrival.
El Niño and travel disruption
One of the challenges for travellers is that the effects of a large-scale weather pattern are not always obvious when a journey is first booked. A flight may still be operating while severe weather is affecting the road network beyond the airport. A destination may remain open while individual attractions, regions or transport routes are temporarily inaccessible. Wildfires can also affect areas several kilometres from the immediate fire zone through smoke and changing air-quality conditions. For international travellers, understanding these wider effects can be just as important as knowing whether a flight is delayed.
Stay informed as conditions develop
The current El Niño event is expected to remain an important factor in weather and health conditions through late 2026 and into 2027. PAHO and WMO are urging governments and health authorities to strengthen surveillance and preparedness as the event develops. (Pan American Health Organization)
For travellers, the key is to monitor destination-specific information rather than treating El Niño as a single global travel warning. Global Traveller provides travel intelligence and location-specific alerts to help international travellers understand developments that may affect their journey, alongside 24/7 access to a human assistance team when travel disruption or other problems arise.
Read more: What Is Travel Intelligence?
Information in this article is current as of 30 September 2026. El Niño-related conditions and their effects can change over time. Travellers should check current destination-specific weather, health and travel information before and during their journey.