Strong El Nino may bring milder winter to Vietnam

The National Centre for Hydro-Meteorological Forecasting said on September 19 that El Nino had reached a very strong intensity and was likely to remain at that level, peaking in the final months of 2026. Its effects could continue into early 2027.

The weather agency said El Nino was likely to remain very strong from January to March 2027, although both the probability of the phenomenon continuing and its intensity were expected to gradually decline.

“Possibility of the phenomenon continuing into the first half of summer 2027 cannot yet be ruled out,” the agency said.

El Nino typically increases the risk of higher temperatures, heatwaves, drought and water shortages, particularly during the dry season. Changes in atmospheric circulation can also alter rainfall patterns and influence the development of storms and tropical depressions.

The weather agency said the number of storms and tropical depressions over the East Sea, as well as those affecting Vietnam's mainland, was likely to be below the long-term average from now until the end of 2026.

During the winter of 2026-27, cold-air activity is expected to be weaker than normal. Severe and extreme cold spells are likely to arrive later and occur less frequently than the long-term average, while temperatures across Vietnam are forecast to be 1-2.5C above average.

Heatwaves could arrive earlier nationwide in early 2027, the agency said. During the summer months, hot weather is expected to be more intense, with more heatwave days than the long-term average and more than in 2026. The possibility of temperatures exceeding historical records cannot be ruled out.

Rainfall from now until the end of 2026 is forecast to remain below average across much of Vietnam, particularly in the south central coast, Central Highlands and southern regions, where deficits are expected to reach about 20-40 per cent. The rainy season in these areas could also end earlier than usual.

The same regions are likely to experience relatively little rainfall during the first months of 2027. Higher temperatures and an early onset of heatwaves are expected to increase water demand and evaporation and transpiration losses.