Colombia is preparing for the first rainy season of the year 2025. Between March and May, the first wave of rain occurs, while the second covers the months of September to November, approximately.
The Institute of Hydrology, Meteorology and Environmental Studies (Ideam) issued alerts on the areas that will experience the heaviest rainfall, while the National Unit for Disaster Risk Management (UNGRD) established the basic points for the preparation of local and regional authorities for possible emergencies.
Colombia prepares for the first rainy season of 2025
The rainy season has been evident in Colombia for some weeks now. Due to the geographic location and territorial diversity of the country, there will be different rainfall patterns depending on the region. Although this season generally extends from March to May, its impact is not uniform throughout the country.
“In the Andean and Pacific regions there will be a significant increase in rainfall, with more intense events in mountainous zones and areas near the coast. On the other hand, in the Caribbean region the rainy season begins with greater incidence from May onwards. Meanwhile, in the Orinoco and Amazon regions there will be an increase in humidity and rainfall, but with a different pattern,” said Ghisliane Echeverry Prieto, director of Ideam.
It is important to clarify that the country is experiencing La Niña conditions. However, the phenomenon has not yet been consolidated and, therefore, Ideam has not officially declared it. For this, it is required that, for at least five consecutive months, the cooling of the waters of the Pacific Ocean and the strengthening of winds are registered.
In this sense, the UNGRD reiterated its call to territorial entities to ensure resources to respond to emergencies caused by floods, landslides, flash floods, torrential floods, gales, hailstorms and thunderstorms.
Considering the vulnerability of some sectors, with the proliferation of self-built houses near rivers and in flood-prone areas, the authorities recommend, as they do every year, to articulate action plans, both in response to possible emergencies and for monitoring vulnerable areas.
According to preliminary figures, between January and February, before the start of the rainy season, nearly 400 rain-related events were recorded, affecting 17,320 families in the country. More than half of the emergencies correspond to landslides affecting homes.
Waiting for the consolidation of the La Niña phenomenon
The La Niña phenomenon is a climatic event characterized by the anomalous cooling of the surface waters of the equatorial Pacific Ocean.
This phenomenon is part of the El Niño-Southern Oscillation (ENSO) climate cycle and occurs when trade winds intensify, causing a rise of cold waters in the equatorial Pacific region.
In Colombia, La Niña has significant effects on the climate, as it generates an increase in rainfall, which increases the risk of flooding, landslides and flash floods in rivers.
The most affected regions are usually the Andean, Pacific and some areas of the Orinoco region. In addition, the persistent humidity may affect agricultural production, causing losses in crops such as coffee, rice and corn.
Experts warn that the effects of La Niña may intensify with climate change, making extreme weather events more frequent and severe. Colombian authorities have reinforced prevention and risk management plans to mitigate impacts on vulnerable communities.
However, for now, El Niño has been the most dominant climate phenomenon in South America, bringing severe droughts and wildfires throughout most of 2024.
Climate experts predict that La Niña will intensify its impact this year. Although early signs of its arrival have appeared, they are not yet strong enough to indicate that the phenomenon has entered a significant phase.
Water rationing in Bogota
However, rainfall is not falling equally throughout the country. While in the Andean, Caribbean and Pacific areas more rain than usual is expected, in the Amazon and Orinoco areas, authorities expect less rainfall than normal.
This could affect the water supply of the capital city of Bogota, which is supplied by water coming from the Orinoco region. The city and its area of influence are suffering from water rationing that began in April last year.
With supply cuts of up to 24 hours per sector every nine days, and despite expected rainfall that could improve reservoir conditions, rationing is not anticipated to end in the short term.
A few weeks ago, the mayor of Bogota, Carlos Fernando Galan, had made statements to the contrary, saying that between April and May the water cuts could end.
Despite the abundant rainfall over Bogota, it will be the rains that fall in the Orinoco area, hundreds of kilometers east of the city, that will determine whether or not the water restrictions will continue for more than 10 million Colombians.