ENSO Tracker - Feb 2022
Sea surface temperature (SST) forecasts for Mar – May 2022 indicate cool conditions across the equatorial Pacific (Fig. 1). Current Nino 3.4/4 anomalies are still below the La Niña threshold (Fig. 2), and ENSO outlooks generally call for La Niña conditions to last through winter 2021-2022 and return to neutral conditions in spring/summer 2022.
Forecast Roundup: On Feb 10 the NOAA Climate Prediction Center (CPC) maintained their “La Niña Advisory” noting “the coupled ocean-atmosphere system reflected a weakening La Niña” and called for a 77-percent chance of La Niña lasting through the Mar-May period, and a 56-percent chance of ENSO-neutral conditions during May-Jul 2022. On Feb 10 the International Research Institute (IRI) issued an ENSO Quick Look (Fig. 3), noting “Sea Surface Temperatures remain below-normal in the central-eastern equatorial Pacific” and “the evolution of key oceanic and atmospheric variables is consistent with weak La Niña conditions”. On Feb 10 the Japanese Meteorological Agency (JMA) observed La Niña conditions are present and an 80-percent chance they would transfer to ENSO neutral by the end of spring. On Feb 15 the Australian Bureau of Meteorology ENSO outlook stated “Atmospheric and oceanic indicators remain at La Niña levels, but have likely peaked in strength”, and called for a “breakdown” in La Niña in the coming months. The North American Multi-Model Ensemble (solid and dashed black line, Fig. 4) remains in La Niña territory, but indicates weak intensity and a gradual transition back to neutral conditions by mid-2022.
Summary: La Niña 2021-2022 is shaping up as a weak event. This event is forecast to last through winter, before moving back to ENSO-neutral conditions in spring or early summer. La Niña winters are frequently warmer and drier than average in the Southwest, and the outlook for the next month and 3 month period reflect this climatological tilt in the odds. December conditions were not exactly canonical (i.e. wetter and at times cooler than anticipated), but January and into February has been much warmer and drier. The impact of La Niña will be assessed in seasonal or longer totals, not weather events on the daily to weekly timescales. The cool season precipitation (Dec-Mar) and water year to date (Oct-Mar) will be instructive as to La Niña's impact, especially since April and May are typically drier regardless of ENSO-phase.
Online Resources
- Figure 1 - Australian Bureau of Meteorology - bom.gov.au/climate/enso
- Figure 2 - NOAA - Climate Prediction Center - cpc.ncep.noaa.gov
- Figure 3 - International Research Institute for Climate and Society - iri.columbia.edu
- Figure 4 - NOAA - Climate Prediction Center - cpc.ncep.noaa.gov