The National Center for Hydro-Meteorological Forecasting has forecasted the weather trend for the season (from January to June 2026).
According to Mr. Nguyen Duc Hoa - Deputy Head of Climate Forecasting Department, National Center for Hydro-Meteorological Forecasting, currently, the ENSO phenomenon is in a La Nina state with the standard deviation of sea surface temperature in the central Pacific (Nino3.4) in the first week of December 2025 at -0.5 degrees Celsius.
"It is forecasted that in the next three months, the ENSO phenomenon is likely to gradually shift to a neutral state with a probability of 60 - 65%. While the probability of a La Nina state is lower than previously forecasts and is only at 35 - 40%.
From April to June 2026: ENSO is likely to maintain a neutral state with a probability of 65-75%, a probability of moving to an El Nino state of about 10 - 25% and a probability of moving to a La Nina state of about 15%." - Mr. Hoa said.
The Deputy Head of the Climate Forecast Department also said that there is little chance of appearing in the East Sea area from January to March 2026. From April to June 2026, storms or tropical depressions in the East Sea will be equivalent to the average of many years, however, the possibility of making landfall in our country is not high.
According to the average data of many years in the period from April to June, there are about 1.8 storms/tropical depressions in the East Sea, 0.3 of which make landfall.
Previously, from the beginning of 2025 to now, there have been 21 storms/tropical depressions active in the East Sea (including 15 storms and 6 tropical depressions). 2025 also became the year with the largest number of storms/tropical depressions active in the East Sea since records began (since 1961). The previous year with the most tropical cyclones was 2017 with 20 storms/tropical depressions.
Regarding the rainfall trend, from January to February 2026, the total rainfall across the country will generally be approximately the same as the average of many years; in the Central and Southern Highlands, it will generally be higher than the average of many years in the same period.
In the Northern region in January-February 2026, the total rainfall will be from 15-35mm/month; in March 2026, the total rainfall will be from 40-70mm.
In the Central region in January 2026, the total rainfall in Thanh Hoa to Ha Tinh provinces will be from 15-35mm; the area from Quang Tri to Hue City and the South Central Coast will be from 50-150mm; the Central Highlands will be from 5-15mm, especially in the south from 15-30mm, some places will be higher.
In February 2026, the total rainfall will be from 15-30mm; in the area from Quang Tri to Da Nang and east of Quang Ngai, it will be from 35 70mm; in the Central Highlands, it will be from 5-15mm, in the south, it will be from 20-50mm, 5-20mm higher, and higher in some places.
In March 2026, the total rainfall will be 30-70mm, the south of the South Central Coast and Central Highlands will be 50-100mm, some places will be 150mm higher, 10-50mm higher than the average of many years.
In the Southern region in January-February 2026, total rainfall will be from 10-30mm, 5-15mm higher than the average of many years, in some places higher. In March 2026, the total rainfall will be 30-70mm, 10-25mm higher than the average of many years.
"Shows and thunderstorms will also appear in the eastern areas of the provinces from Quang Ngai to Dak Lak and Khanh Hoa in the second half of December 2025 and January 2026" - Mr. Hoa said.
Some concepts of ENSO according to the Institute of Meteorology, Hydrology and Climate Change:
El Nino: El Nino is a concept used to refer to the phenomenon of abnormal warming of the surface water layer in the eastern equatorial Pacific Ocean. El Nino is also known as the "hot spot".
La Nina: In contrast to El Nino, La Nina is a concept used to refer to the abnormal cold phenomenon of the surface water layer in the eastern equatorial sea of the Pacific Ocean. La Nina is also known as the "cold flood".
Southern fluctuations (SO): SO is a concept used to refer to the fluctuation phenomenon of the pressure difference between the western and central equatorial Pacific.
ENSO: Because the two phenomena El Nino/La Nina (ocreatic) and SO ( atmospheric) occurring on the equator TBD are closely related, they are linked together into a dual phenomenon, abbreviated as ENSO.
