November 2024 Climate Forecast Discussion
November 2024 Climate Forecast Discussion for the period Dec-Feb 2025 through Mar-May 2025
During October 2024, slightly negative sea surface temperature (SST) anomalies persisted over the central-eastern equatorial Pacific Ocean, leading to a NINO3.4 anomaly index value of -0.28 °C. The weekly-averaged SST anomalies in the NINO3.4 region were -0.3 °C for the week centered on Nov 06, 2024. This indicates an ongoing ENSO-neutral state in the equatorial Pacific Ocean. According to the early-November CPC ENSO forecast,La Niña is favored to emerge in Oct-Dec, 2024 with 57% chances, and is expected to stay through Jan-Mar 2025. The Indian Ocean Dipole (IOD) index is neutral. The North Atlantic Ocean continues to exhibit persistent warm sea surface temperature (SST) anomalies that are forecast to continue for the next couple of months, while the Indian Ocean Dipole is forecasted to be at the negative threshold for a short time.
IRI's seasonal precipitation forecasts issued in November 2024 indicate chances of above-normal rainfall in the northwest US and Alaska region, Central America, northern parts of South America, the Maritime Continent, and parts of Australia during Dec-Feb and Jan-Mar 2025. These probabilities become very weak during Feb-Apr and Mar-May 2025 over the above-mentioned regions. An increased probability of above-normal precipitation is also forecasted for South Asia and Southeast Asia during Feb-Apr and Mar-May 2025. An increased probability of below-normal precipitation is forecasted for most of the Southern U.S. and Mexico for most of the forecast period. The probability of below-normal precipitation is also forecasted over various parts of South America, including tropical northeast South America, areas around Uruguay, southern Chile, scattered parts in equatorial East Africa, and the Middle East during the forecast period, although the strength of this probability decreases towards the end of the forecast period. Many, while not all, of these precipitation patterns align with historical La Niña events and are consistent with the La Niña forecast in boreal winter and early spring of 2025.
Regarding temperature, strongly enhanced probabilities for above-normal temperatures are forecasted across most land areas throughout the forecast period. The forecast shows elevated probabilities (though weak) of below-normal temperatures over parts of western Canada, the central U.S., and Alaska during Dec-Feb and Jan-Mar 2025. The temperature forecasts indicate the dominant category of normal temperatures during Feb-Apr and Mar-May, 2025 over South Asia, Southeast Asia, and the Australia region.