Tehuantepecer

It originates from eastern Mexico and the Bay of Campeche as a post-frontal northerly wind, accelerated southward by cold air damming, that crosses the isthmus and blows through the gap between the Mexican and Guatemalan mountains.

These strong winds bring cooler sub-surface waters to the surface of the tropical eastern Pacific Ocean and may last from a few hours to 6 days.

The synoptic condition is associated with the formation of high-pressure systems in Sierra Madre in the wake of an advancing cold front.

[3] It leads to a localized acceleration of the trade winds in the region, and can enhance thunderstorm activity when it interacts with the Intertropical Convergence Zone.

[5] These strong winds upwell sub-surface waters, cooling the tropical eastern Pacific Ocean by as much as 14 °F (9 °C),[7] and may last 4–7 days.