Tehuano Wind: Strong Gap Winds over the Gulf of Tehuantepec
In southern Mexico, a powerful regional wind known as the Tehuano (or Tehuantepecer) can turn the Gulf of Tehuantepec into one of the windiest spots in the eastern Pacific. These strong northerly winds blow through a narrow gap in the mountains, linking the Gulf of Mexico with the Pacific Ocean.
Where Does the Tehuano Blow?
The Tehuano focuses on:
- The Isthmus of Tehuantepec in southern Mexico
- The Gulf of Tehuantepec on the Pacific side
- Offshore waters stretching hundreds of kilometres into the eastern Pacific
The Sierra Madre mountains are lower over the isthmus, creating a natural corridor for air to flow from north to south.
When Are Tehuano Events Most Common?
Tehuano winds are most frequent:
- In autumn and winter, especially from November to March
- Following cold fronts that move southward into the Gulf of Mexico
How Do Tehuano Winds Form?
Typical ingredients for a Tehuano event:
- A strong high‑pressure system builds over the Gulf of Mexico and interior Mexico after a cold front.
- Pressure is lower over the eastern Pacific off the coast of Oaxaca and Chiapas.
- Air accelerates from north to south through the gap of the Isthmus of Tehuantepec.
- As it descends toward the Pacific, it can reach gale or even storm force, creating a powerful northerly or northeasterly wind over the Gulf of Tehuantepec.
Impacts at Sea and on Land
Tehuano events can produce:
- Very rough seas and large waves, hazardous for shipping and fishing boats
- Strong offshore winds that can extend far out over the Pacific
- Dust and spray, reducing visibility near the coast
On land, the winds can cause:
- Local tree and infrastructure damage in exposed areas
- Rapid changes in temperature and humidity
For meteorologists and oceanographers, Tehuano winds are an important example of gap winds – strong flows driven by pressure differences and funnelled through a mountain pass, with significant impacts on both regional weather and ocean conditions.
