According to the National Center for Hydro-Meteorological Forecasting, on the afternoon of 16/4, a weak cold air mass continued to move southward, pressing down on a low-pressure trough with an axis around 24-26 degrees north latitude.

From the night of 16/4 to 17/4, influenced by this weather pattern combined with wind convergence at 1,500 m, the Northern and North Central regions will experience rain, moderate rain, and scattered thunderstorms, with common rainfall amounts of 20-40 mm, and some localized areas receiving over 100 mm. From 17/4, the Northern region will turn cooler.

On the evening of 16/4, the Central Highlands region will have scattered showers and thunderstorms, with rainfall amounts of 10-20 mm, and some areas exceeding 50 mm.

The center warns that during thunderstorms, whirlwinds, lightning, hail, and strong gusts may occur, causing damage to agricultural production, breaking trees, and damaging homes and infrastructure. Localized heavy rain poses a risk of flash floods in small rivers and streams, landslides in sloping areas, and inundation in low-lying regions.

The meteorological agency also stated that forecasting whirlwinds and thunderstorms can currently only be done 30 minutes to three hours in advance, with an accuracy of about 70-90%. Residents need to closely monitor weather reports, limit outdoor activities during thunderstorms, proactively secure their homes, and protect property and vehicles.

Hail shattered car windows in Bac Ha on the morning of 16/4. *Photo: Ngoc Nhung*.

The Department of Dyke Management and Disaster Prevention and Control (Ministry of Agriculture and Environment) advises residents to take proactive precautions early. Homes, especially corrugated iron roofs, billboards, and temporary structures, should be securely reinforced; surrounding trees should be trimmed to prevent breakage; and electrical systems should be checked for safety.

During whirlwinds and thunderstorms, residents should stay in sturdy homes, close doors and windows, and stay away from windows and objects easily carried by the wind; do not seek shelter under large trees or utility poles, or stand in open areas; limit the use of electrical appliances, and disconnect power when not necessary.

In case of hail, quickly seek safe shelter, prioritizing personal protection, and avoid standing under weak corrugated iron roofs or temporary structures. If outdoors, find a low-lying position, stay away from metal objects and hazardous areas.

After the disaster, residents need to check electrical systems before use, be wary of broken power lines, fallen trees, and areas at risk of landslides or deep flooding.

Early on 16/4, hail lasting about 15-30 minutes occurred in Bac Ha commune, Lao Cai province, with high density and many stones 5-7 cm in diameter, causing a rumbling sound. Thunderstorms accompanied by strong winds broke fiber cement roofs and window panes, and damaged crops. Initial statistics recorded 4 injured people, over 330 damaged homes, and nearly 500 ha of crops affected.

Gia Chinh