February 2025 Climate Forecast Discussion
February 2025 Climate Forecast Discussion for the period Mar-May 2025 through Jun-Aug 2025
**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-IC4, COLA-RSMAS-CESM1, GFDL-SPEAR, and NASA-GEOSS2S models. The climatological base period for normal is 1991-2020. The SST anomalies cited below refer to the OISST.v2.1 SST data set. Starting from June 2024, the observed climatology used to compute the dry mask was updated to 1991-2020, and the criterion modified to mask points where 10% of the training sample (i.e. 3 or more years) received less than or equal to 1 mm over a 3-month season.
During January 2025, negative sea surface temperature (SST) anomalies intensified slightly over the central-eastern equatorial Pacific Ocean, leading to a NINO3.4 anomaly index value of -0.71 °C. However, the weekly-averaged SST anomalies in the NINO3.4 region were -0.6 °C for the week centered on Feb 05, 2025. This indicates the ongoing La Niña conditions in the equatorial Pacific Ocean. According to the early-February NOAA CPC ENSO forecast, a La Niña Advisory remains in effect and La Niña conditions are expected to persist in the near-term, with a transition to ENSO-neutral likely during March-May 2025 (66% chance). The Indian Ocean Dipole (IOD) index is neutral, and the North Atlantic Ocean continues to exhibit persistent warm sea surface temperature (SST) anomalies.
The IRI's seasonal precipitation forecasts issued in February 2025 indicate a weak above-normal probability for precipitation in the northern parts of the US bordering Canada, the Southeastern US, Central America, northern South America, Siberia, Southeast Asia, the Maritime Continent region, and parts of Australia during March-May 2025. Conversely, substantially enhanced below-normal precipitation probability is forecasted for the southern and southwestern parts of the US, southern Chile, eastern Europe, central Southwest Asia, northern China, and equatorial central and east Africa during the same period (March-May, 2025). The above-normal precipitation probabilities in northern North America and central and northern South America fade away in subsequent forecast seasons. Meanwhile, the below-normal probability areas in the Southern and Southwestern US gradually move northward. In Central and South America, below-normal probability emerges, interspersed with weak above-normal probability spots. Starting in May-July, the forecasts point to a gradually increasing probability of above-normal precipitation over the African Sahel and South Asia, as those regions enter their rainy seasons.
Regarding temperature, most land areas are forecasted to have significantly higher probabilities of above-normal temperatures throughout the forecast period. However, the temperature forecasts also indicate increased chances of below-normal temperatures over the west coast of Canada in March-May and slightly increased chances of below-normal temperatures in certain regions during June-August 2025, including parts of South Asia (e.g., Indian Peninsula) and Southeast Australia.