February 2023 Climate Forecast Discussion
Feb 2023 Climate Forecast Discussion for Mar-May through Jun-Aug 2023
In January 2023, equatorial sea surface temperatures (SSTs) in the central-eastern Pacific Ocean remained cooler than normal, exhibiting persistent La Niña conditions (the NINO3.4 index value in January 2023 was -0.75C). The most recent weekly (08 Feb 2023) anomaly in the NINO3.4 region was -0.5 °C, showing a weakening of the current La Niña conditions in the tropical Pacific. According to the early-February CPC ENSO forecast, a transition from La Niña to ENSO-neutral is highly likely in the next couple of months (94% chance during Mar-May 2023), with ENSO-neutral becoming the most likely category during boreal spring and early summer. No strong SST anomalies are present in the tropical Indian Ocean, while the Atlantic Ocean shows weak warm anomalies in both observations and the model forecasts.
The combined model precipitation forecasts for Mar-May 2023 show enhanced probabilities of below-normal precipitation over northern Mexico and the southwestern US. Enhanced probabilities of above-normal precipitation are forecast over much of northeastern South America, parts of southern Africa, Southeast Asia, and especially the Philippines during Mar-May and Apr-Jun. The forecasts for May-Jul and Jun-Aug indicate enhanced probabilities of above-normal precipitation over the African Sahel and central South America. Beyond March-May, precipitation forecasts are very uncertain, and should therefore be interpreted with caution.
For temperature, moderately to strongly increased probabilities of above-normal temperatures are forecast over most land areas throughout the forecast period. Weakly enhanced probabilities of below-normal temperatures are forecast in Mar-May 2023 for northwestern Canada and Alaska, some parts of northern South America, parts of Madagascar, and parts of northeast Australia. These weak probabilities of below-normal temperatures mostly disappear in subsequent seasons, except over Madagascar, while the tilt of the odds toward above-normal temperatures holds for rest of the forecast period over most land areas.
Citation
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