The Instituto Meteorológico Nacional (IMN) – national weather service – is predicting that the “Veranillo de San Juan” (Indian Summer) will only occur in Guanacaste this year, this beacuse the trade winds do not favour the presence of the phenomenon in the rest of the country.
According to IMN meteorologist Juan Diego Naranjo, the Veranillo, that usually occurs between June 21 and 25 each year, will be felt mainly in the northern zone and possibly in some parts of the Central area.
Historically, the “veranillo” appears near June to mark the birth of San Juan Bautista (John the Baptist).
Weather experts assure that the possibility of the phenomenon spreading to the entire country this year, is neglible.
The Veranillo of San Juan occurs in South America and Central America during what is traditionally known as the “green season” or “rainy season” (“invierno” or “winter”, locally here in Costa Rica). It is basically an interruption of the rainy season.
El Veranillo de San Juan manifests itself south of the Tropic of Capricorn not only in Costa Rica and Nicaragua, but in the South American countries of Argentina, Paraguay, Chile, and Uruguay, where colder winter temperatures abruptly rise for a month, then fall back to their chilly regularity.
In Costa Rica, it’s less about temperature than it is about precipitation, when suddenly the skies turn blue, the rain abates and the humidity drops.