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ENSO Tracker - Aug 2022 | CLIMAS

 SW Climate Outlook

ENSO Tracker - Aug 2022

ENSO Tracker - Aug 2022

Sea surface temperature (SST) forecasts for Aug – Oct 2022 continue to call for cooler than average conditions across most of the equatorial Pacific (Fig. 1), and the current 3.4/4 anomalies remain below the La Niña threshold (Fig. 2). ENSO outlooks generally call for La Niña to last well into fall and possibly through winter.

Forecast Roundup: On Aug 16 the Australian Bureau of Meteorology raised their ENSO outlook “La Niña ALERT”, noting “renewed cooling in the tropical Pacific” and “climate models indicating La Niña is likely” through early winter. On Aug 10 the Japanese Meteorological Agency (JMA) observed La Niña conditions had a 60-percent chance of continuing into early winter, and a 40-percent chance of returning to ENSO-neutral. On Aug 11 the NOAA Climate Prediction Center (CPC) maintained their “La Niña Advisory” noting “the coupled ocean-atmosphere system remained consistent with an ongoing La Niña” and called for an 86-percent chance of La Niña through fall, and a 60-percent chance of La Niña in winter. On Aug 11, the International Research Institute (IRI) issued an ENSO Quick Look (Fig. 3), noting below-average SSTs and that “oceanic and atmospheric variables have remained consistent with La Niña, although weakened”. The North American Multi-Model Ensemble (solid and dashed black line, Fig. 4) is currently forecast to remain under the La Niña temperature threshold through fall and into winter.

Summary: La Nina appears to have persisted through summer, and now the primary question is how long it will last this fall and winter. The La Nina signal is likely to suppress eastern Pacific tropical storm activity, which can tamp down late season monsoon activity. If La Nina conditions persist into early winter, the Southwest can anticipate seasonal outlooks that call for below average winter precipitation, based on the relatively strong link between La Nina and below average cool season precipitation.

Online Resources

  • Figure 1 - Australian Bureau of Meteorology -
  • Figure 2 - NOAA - Climate Prediction Center -
  • Figure 3 - International Research Institute for Climate and Society -
  • Figure 4 - NOAA - Climate Prediction Center -