Very strong El Nino to fuel heat, drought, extreme weather in Vietnam through 2027

The National Center for Hydro-Meteorological Forecasting forecast that El Nino would maintain its very strong intensity and peak in the final months of 2026, with its effects potentially lasting into early 2027.

The agency made the assessment while updating its latest observations of El Nino and forecasting potential impacts in the coming months.

El Nino could persist until summer 2027

As of the second week of September 2026, the sea surface temperature anomaly in the NINO3.4 region had risen to around 2°C, reaching the threshold for a very strong El Nino event.

Climate forecasts indicate that El Nino is almost certain to remain very strong from October through December and could reach its peak during this period.

From January to March 2027, El Nino is likely to remain very strong, although both the probability and intensity are expected to gradually decline.

The possibility that the phenomenon could persist into the first half of summer 2027 has not been ruled out.

Given this development, the weather agency said El Nino would have increasingly pronounced impacts in the coming months, including raising the risk of higher temperatures, heatwaves, drought and water shortages, particularly during the dry season.

Changes in atmospheric circulation could also alter rainfall patterns and affect the activity of storms and tropical depressions.

From now through the end of 2026, the number of storms and tropical depressions over the East Vietnam Sea and those affecting Vietnam is expected to be lower than the long-term average.

However, fewer storms do not mean that strong storms will not occur, while less widespread rainfall does not mean extreme rainfall events will be absent.

During strong El Nino years, very heavy rainfall, floods, flash floods, landslides and storms that develop unpredictably can still occur due to the combined effects of regional-scale weather patterns and short-term atmospheric conditions.

Very high risk of drought, water shortages, saltwater intrusion

Due to the effects of El Nino, temperatures are forecast to remain high during the winter of 2026-27, while cold-air activity is expected to be weaker than normal.

Cold spells and severe cold are likely to arrive later and occur less frequently than the long-term average.

Average temperatures across Vietnam are forecast to be 1-2.5°C higher than the long-term average.

In early 2027, heatwaves could occur earlier than usual nationwide.

During the summer months of 2027, heatwaves are expected to be intense, with more heatwave days than the long-term average and more than in 2026. Temperatures exceeding historical records cannot be ruled out.

Rainfall from now through the end of 2026 is expected to be below normal across most of the country, particularly along the south-central coast, the Central Highlands and southern Vietnam, with deficits of 20-40 percent expected in these areas.

The rainy season in these regions could also end earlier than usual.

These areas are likely to continue experiencing below-normal rainfall in the first months of 2027. Meanwhile, higher temperatures and early heatwaves will increase water demand and evaporation.

As a result, the risk of drought, water shortages and saltwater intrusion during the dry season in early 2027 is considered very high along the south-central coast, in the Central Highlands and southern Vietnam.

The National Center for Hydro-Meteorological Forecasting said El Nino is a large-scale climate phenomenon and its signal alone cannot be used to accurately predict a specific natural disaster in a particular locality.

The extent of its impacts also depends on interactions between El Nino and atmospheric and oceanic systems, as well as weather patterns during specific periods and seasons.

Vietnam’s weather agency has advised localities to prepare for both groups of risks as El Nino has reached a very strong level and shows signs of intensifying further.

On one hand, heavy rain, storms, floods and other extreme weather events could occur at specific times.

On the other, heatwaves, drought, water shortages and saltwater intrusion could persist during the 2026-27 dry season.