April Climate Briefing: Models Say Weak El Niño Will Continue

Read our ENSO Essentials & Impacts pages for more about El Niño and La Niña.

Tony Barnston provides an overview of the briefing:

What’s New

An abbreviated briefing update this month. See below for tweets summarizing the current El Niño situation, and our update from March for much more on how this ENSO event has evolved.

ENSO Forecasts

To predict ENSO conditions, computers model the SSTs in the Niño3.4 region over the next several months. The plume graph below shows the outputs of these models, some of which use equations based on our physical understanding of the system (called dynamical models), and some of which use statistics, based on the long record of historical observations.

The probability for El Niño conditions to continue is high in the coming months. El Niño conditions are the most likely outcome through the end of the forecast period. The El Niño odds are somewhat lower in the official probabilistic forecast issued by CPC and IRI in early April than in this mid-month CPC/IRI forecast. This early-April forecast uses human judgement in addition to model output, while the mid-month forecast relies solely on model output. More on the difference between these forecasts in this IRI Medium post.

ENSO in context: Resource page on climate variability

IRI’s Global Seasonal Forecasts

Each month, IRI issues seasonal climate forecasts for the entire globe. These forecasts take into account the latest model outputs and indicate which areas are more likely to see above- or below-normal temperatures and precipitation.

All forecast maps, including temperature in addition to precipitation, and also including a description of the methodologies, are available on our seasonal forecast page. Additional forecast formats, such as our flexible forecast maproom, are available in the IRI Data Library.

Learn more about El Niño and La Niña on our ENSO resources page, and sign up here to get notified when the next forecast is issued. In the meantime, check out #IRIforecast.