Northern and central Vietnam are entering what forecasters say could become the longest and most intense heatwave since the start of the season, while southern provinces are expected to see increasing thunderstorms. Meteorologists are also warning that the East Sea could witness its first tropical storm or depression within the next month.

Severe heat spreads across northern and central Vietnam

According to Vu Tuan Anh from the Weather Forecast Department under the National Center for Hydro-Meteorological Forecasting, the western low-pressure heat system has intensified again, causing temperatures to rise sharply across northern and central regions starting May 22.

On May 22, the northern delta region and southern Phu Tho are expected to experience widespread heat with maximum temperatures ranging from 35-36 degrees Celsius, with some areas exceeding 36 degrees.

The same day, provinces stretching from Thanh Hoa to Da Nang, along with eastern areas from Quang Ngai to Dak Lak, will also face hot weather conditions, with some locations experiencing severe heat reaching 35-37 degrees Celsius and isolated areas surpassing 37 degrees.

By May 23, the heatwave is forecast to intensify further and expand across most northern and central provinces.

In northern Vietnam, temperatures are expected to range from 35-37 degrees Celsius, with some areas exceeding 37 degrees.

Meanwhile, areas from Thanh Hoa to Da Nang and eastern provinces from Quang Ngai to Dak Lak could see temperatures between 36-38 degrees Celsius, with isolated areas climbing above 38 degrees.

According to forecaster Tuan Anh, central Vietnam will also be affected by foehn winds, locally known as Lao winds, which are expected to make conditions even hotter and drier.

“The peak of this heatwave is forecast between May 24 and 27. Maximum temperatures in northern and central Vietnam could range from 36-39 degrees Celsius. In some northern areas and western mountainous regions from Thanh Hoa to Hue, temperatures above 39 degrees Celsius cannot be ruled out,” he said.

Compared with the previous heatwave from May 13-16, this latest spell is forecast to be both more intense and longer-lasting.

Meteorologists also warned that actual outdoor temperatures may be 2-4 degrees Celsius higher, especially in densely built urban areas with asphalt roads and concrete surfaces.

Prolonged heat combined with low humidity is expected to increase the risk of fires and explosions while posing health threats to elderly people, children and outdoor workers.

The weather agency forecasts that the widespread heatwave in northern Vietnam will continue from May 23-27 before scattered showers and thunderstorms arrive late on May 27, bringing some relief.

In central Vietnam, particularly from Thanh Hoa to Da Nang and eastern areas from Quang Ngai to Dak Lak, the heatwave is expected to persist through May 27 or 28 before gradually easing and becoming more localized.

Southern Vietnam enters stronger rainy season pattern

Southern Vietnam is now showing increasingly clear signs of the rainy season as the southwest monsoon becomes more stable and gradually strengthens, effectively ending the prolonged widespread heat experienced earlier this year.

Starting May 22, southern provinces are forecast to experience scattered showers and thunderstorms during the late afternoon and evening hours.

From the evening of May 27 onward, stronger southwest monsoon activity is expected to bring more widespread rainfall, with localized heavy downpours possible.

Elsewhere, scattered showers and thunderstorms are expected to continue in many areas.

In the Central Highlands, more regular afternoon and evening rain and thunderstorms are forecast beginning around May 27.

Meteorologists warned that thunderstorms could bring dangerous weather phenomena including tornadoes, lightning, hail and strong winds.

Storm warning issued for East Sea

Nguyen Duc Hoa, Deputy Head of the Weather Forecast Department, said average temperatures nationwide from May 21 to June 20 are expected to remain 0.5-1 degree Celsius above long-term averages, with some areas potentially recording even higher anomalies.

Rainfall in the Central Highlands and southern Vietnam is forecast to exceed average levels by 5-25%, while other regions are expected to remain near normal.

Most notably, forecasters say the East Sea could witness the formation of a tropical storm or tropical depression within the next month, with activity expected to align with long-term averages for the period - around 0.9 storms at sea and 0.2 storms making landfall in Vietnam.

From now until late June, heatwaves are expected to intensify further across northern and central Vietnam, while widespread heat in the Central Highlands and southern Vietnam is likely to largely disappear.

Widespread heavy rainfall is forecast to continue affecting northern Vietnam, the Central Highlands and southern provinces, while localized thunderstorms remain likely elsewhere.

Given increasingly complex weather patterns, experts urged local authorities and residents to closely monitor short-term forecasts over the next one to three days in order to adjust production plans and prepare timely response measures.

Bao Anh