El Niño 2026–27 in Mexico

Outlook for the next six months

In the tropics, seasonal forecasts generally have useful skill during strong El Niño years, but they give odds, not certainties. “Normal” means the middle third of the model's own 1993–2016 range; because the climate has warmed since then, “warmer” is the usual result almost everywhere.

Source: Copernicus Climate Change Service seasonal forecast (Copernicus Climate Change Service (C3S) seasonal forecasts, ECMWF system 51), country average. How this is calculated.

Air quality, next 4 days

Worst forecast day: Mexico City, 16 November 2026: Unhealthy for Sensitive Groups (PM2.5 44.7 µg/m³, AQI 124).

AQI = US EPA 24-hour PM2.5 scale (2024). Model forecast for an area of about 40 km, not a local measurement. Local levels can be higher or lower. Dates are UTC days.

Source: Copernicus Atmosphere Monitoring Service global forecast, run 2026-11-14 00 UTC.

What happened in past El Niños

Each row compares El Niño seasons with all other years in 1979-2025, after removing the long-term trend.

Source: ERA5 monthly reanalysis (Copernicus Climate Change Service); El Niño seasons from NOAA's Oceanic Niño Index. Method.

What you can do

If it turns out wetter

• Find out whether your home, school or workplace is in a flood-risk area, and know your evacuation route.
• Clear gutters and drains before the rainy months.
• Keep important documents, medicines and a torch in a waterproof bag.
• After heavy rain, avoid walking or driving through flood water and follow local advice on drinking water and mosquito-borne disease.

If it turns out drier

• Follow water-use notices from your local water utility, and fix leaks early.
• Farmers: check planting advice and drought bulletins from the national agriculture and weather services before the season.
• Clear dry vegetation near homes where wildfires are possible, and know your local fire-danger rating.
• Keep a few days of drinking water stored if supply cuts have happened in past dry years.

If it turns out hotter

• Check on older relatives, neighbours and anyone who lives alone during hot spells.
• Drink water regularly, and avoid hard outdoor work in the hottest hours.
• Know the signs of heat exhaustion (dizziness, headache, nausea) and when to get medical help.

On smoky or hazy days

• Check the daily air-quality forecast and cut down hard outdoor exercise when it is 'Unhealthy' or worse.
• A well-fitted N95 or KN95 mask reduces smoke exposure; cloth and surgical masks do much less.
• Keep windows closed and use an air purifier with a HEPA filter if you have one.
• People with asthma, heart or lung disease, older people, children and pregnant people should take extra care.