La Niña is currently active and expected to persist for the next three months, creating unpredictable weather patterns in 2025, including cold spells, heatwaves, and storms.

The impact of La Niña and weather outlook

Dr. Hoang Phuc Lam, Deputy Director of the National Center for Hydro-Meteorological Forecasting, provided insights into Vietnam’s climate trends for 2025.

As of early January 2025, the ENSO phenomenon remains in a La Niña phase, with sea surface temperature anomalies in the central equatorial Pacific measuring -0.7°C below the long-term average.

La Niña is projected to persist with a 55-65% probability through February to April 2025, after which ENSO conditions are likely to shift to a neutral state by May and maintain this status for the remainder of the year.

With these trends, Vietnam faces a high likelihood of extreme and unpredictable weather events.

From January to June 2025, cold spells will continue to be intense in January and February, potentially causing severe cold, frost, and hoarfrost in mountainous areas. From March onwards, cold air intensity will gradually weaken.

Storms and tropical depressions

From January to April, storms and tropical depressions are expected to have minimal activity in the East Sea, with numbers near the average (approximately 0.4 storms in the East Sea and none making landfall).

Between May and June, storm activity is projected to remain average, with around 1.6 storms forming in the East Sea and 0.3 storms potentially making landfall.

More intense heatwaves anticipated

Heatwaves in 2025 are expected to surpass the annual average in both frequency and intensity.

From February to April, heatwaves will likely occur at levels similar to the average, primarily affecting the northwest, central, and southern regions. However, their intensity is anticipated to be less severe than in 2024.

By May and June, heatwaves will expand in the northern region, reaching the eastern areas, while central Vietnam will experience prolonged periods of high temperatures.

Extreme heat and intense heatwaves are forecast to be more frequent than average in northern and central Vietnam, with particular concern for severe and prolonged heat in these areas.

In the southern and Central Highlands regions, heatwaves will persist through May and taper off by June.

During this period, average temperatures are predicted to align with historical norms, except in April, when northern and north-central Vietnam could see temperatures 0.5–1°C higher than average.

Weather trends for July to December 2025

From July to December, storms and tropical depressions in the East Sea are expected to be consistent with historical averages, primarily impacting northern provinces from July to September and central and southern regions from September to December.

Heatwaves will likely continue in northern and central regions from July to September, exceeding average levels.

The meteorological agency also warns of potential strong winds and high waves in the East Sea during the latter half of the year, driven by storms, tropical depressions, and the southwest monsoon. Cold air surges from October to December may further exacerbate these conditions.

Thunderstorms, lightning, hailstorms, and heavy rains could adversely affect agricultural activities and livelihoods, particularly in vulnerable areas.

Reflecting on 2024’s record-breaking weather
Dr. Lam noted that 2024 saw 10 storms and one tropical depression in the East Sea. Typhoon Yagi, the third storm of the season, was the strongest in 30 years, causing significant damage to lives and property.

Additionally, extreme weather events, including heatwaves and cold spells, shattered historical temperature records, underscoring the increasing volatility of Vietnam’s climate.

Bao Anh