El Niño Hits Very Strong Intensity and Could Last Until June 2027

• El Niño in the equatorial Pacific has reached very strong intensity and could persist until June 2027, spanning Costa Rica’s entire upcoming dry season and the start of the next rainy one. That is longer and stronger than the National Meteorological Institute (IMN) projected in May, when it expected the event to reach strong intensity late this year and weaken in early 2027.
• Sea surface temperatures in the Niño 3.4 region ran about 2.5 degrees Celsius (4.5 degrees Fahrenheit) above normal in August, warmer than the same stretch of the benchmark 1997 and 2015 events. IMN meteorologist Daniel Poleo said the anomaly already qualifies as extraordinary, the label used once it passes 2 degrees Celsius (3.6 degrees Fahrenheit), and is the highest in 38 years of records, with the event likely to gain a little more force.
• Subsurface pockets running up to 6 degrees Celsius (10.8 degrees Fahrenheit) above average are expected to drift toward the coast of South America and rise, lifting surface temperatures further. Because El Niño typically peaks late in the year, current readings are unlikely to be the maximum.
• The IMN drought early warning system already places the Pacific slope, the Central Valley and the western Northern Zone, including Guatuso, Los Chiles and Upala, under meteorological drought, and Poleo expects those conditions to hold rather than ease. September is on track to close with the North Pacific roughly 80% below normal rainfall, the Central and South Pacific 60% below, the Central Valley 50% below and the western Northern Zone 10% below.
• The Caribbean is the usual El Niño exception, with the North Caribbean set to end the month about 20% wetter than normal and the South Caribbean about 30% wetter, leaving one side of the country flooding while the other dries out. From October through December the Caribbean and the eastern Northern Zone should return to normal rainfall while the western Northern Zone runs about 30% short.
• Over the same period, the Pacific and the Central Valley will slide early into dry season conditions, with rains ending ahead of schedule, above-average temperatures and a late, weaker season of cold surges from the north. Anyone relying on a well, rainwater tank, river intake or reservoir faces an extended stretch rather than a passing dry spell, though Poleo cautioned that a very strong El Niño does not scale up every impact proportionally and Costa Rica has no comparable event in the last 40 or 50 years to forecast from.

(Source: The Tico Times)