April 2022 Climate Forecast Discussion

April 2022 Climate Forecast Discussion for May-Jul through Aug-Oct 2022

Note:The IRI seasonal forecasts of precipitation and temperature issued this month are based on an objective calibration procedure that combines the NCEP-CFSv2, CanSIPS-IC3, COLA-RSMAS-CCSM4, and GFDL-SPEAR, and NASA-GEOSS2S models. The climatological base period for normal is 1991-2020.

In March 2022, the equatorial sea surface temperatures (SSTs) in the central-eastern tropical Pacific Ocean were below average and the tropical Pacific atmosphere remained consistent with La Niña conditions. The early-April CPC/IRI ENSO forecast indicates a continuation of the weak La Niña during the Northern Hemisphere summer with 59% chance in Jun-Aug 2022, and near-equal odds (50-55%) through Aug-Oct, indicative of large uncertainty. All five models used in IRI’s seasonal climate forecast, predict cooler than average SSTs over the eastern tropical Pacific and a continuation of the current La Niña episode except GFDL-SPEAR which shows ENSO-neutral conditions. This has significant impacts on the seasonal forecasts of precipitation and temperature across the globe. No strong SST anomalies are present in the tropical Indian and Atlantic Oceans in both observations and the forecast.

Forecasts show enhanced probabilities of below-normal precipitation in the Northwest United States, southern South America, and Turkey and Central Southwest Asia in May-Jul and Jun-Aug, while weakened probabilities are forecasted during Jul-Sep and Aug-Oct over these regions. Moderately enhanced probabilities of below-normal precipitation are forecasted over scattered parts of southern Africa during Jul-Sep and Aug-Oct. Enhanced probabilities of above-normal precipitation are forecasted for the African Sahel, many parts of the Asian and some parts of the American monsoon regions during the forecast period. Very high probabilities are also forecasted over most of the Maritime continent, and Australia during the forecast period, with increasingly high probabilities toward the end of the forecast period in Aug-Oct.

High probabilities of above-normal temperatures are forecast over the majority of land areas, while moderate probabilities of below-normal temperatures are forecast for African, and Asian monsoon regions during the forecast period. Weak probabilities of below-normal to near-normal temperatures are also forecasted over parts of central and northwestern regions of South America, southern South Africa, and Australia during the forecast period.