However, heavy rainfall continues in Thanh Hoa and Nghe An provinces, heightening the risk of flash floods and landslides.

As of 1:00 PM on July 22, the storm’s center was located at approximately 20.1°N latitude and 106.0°E longitude, over the mainland of Ninh Binh and Thanh Hoa provinces. Maximum wind speeds near the center reached level 8 (62-74 km/h), with gusts up to level 10. The storm is moving west-southwest at 10–15 km/h and is expected to weaken into a tropical depression.

During the afternoon, the Gulf of Tonkin - including Bach Long Vi, Co To, Van Don, Cat Hai, Hon Dau, and Hon Ngu islands - experienced winds at level 6–7, with level 8 gusts near the storm’s center and waves reaching 2.0–4.0 meters in height, resulting in rough seas.

Storm surge warnings have been issued for coastal regions: sea levels rose by 0.4–0.8 meters from Quang Ninh to Ninh Binh due to storm circulation.

As of the afternoon of July 22, coastal water levels continued to rise with the tide and storm surge. Water levels reached 2.8–3.1 meters in Ba Lat (Hung Yen), 3.9–4.2 meters in Hon Dau (Hai Phong), and 4.4–4.8 meters in Cua Ong (Quang Ninh), raising serious concerns about flooding in coastal and river mouth areas.

According to the National Center for Hydro-Meteorological Forecasting, the storm is expected to continue moving west-southwest at 10–15 km/h over the next 24 hours, weakening first into a tropical depression and then into a low-pressure area.

From July 22 to 23, the southern region of the Northern Delta, along with Thanh Hoa and Nghe An, is forecast to experience very heavy rainfall and thunderstorms, with total precipitation ranging from 100–200 mm and locally exceeding 300 mm. Other areas in the Northern Region and Ha Tinh may experience moderate to heavy rainfall and thunderstorms, with amounts ranging from 20–50 mm, and locally over 100 mm.

There is a warning of high-intensity rainfall (more than 150 mm within 3 hours). Intense rainfall in a short period could trigger flash floods, landslides in mountainous areas, and flooding in low-lying regions.

Why different areas experienced contrasting weather during Storm No. 3

On the morning of July 22, while affected by the same storm system, weather varied significantly across different regions: some places experienced heavy rain and strong winds, while others saw sunshine.

Hoang Phuc Lam, Deputy Director of the National Center for Hydro-Meteorological Forecasting (Department of Meteorology and Hydrology, Ministry of Agriculture and Rural Development), explained that not all storm clouds produce rain. Storm systems contain various cloud layers, with high-altitude clouds sometimes only blocking sunlight. As a result, some areas may appear cloudy without rain, or may experience brief showers followed by dry intervals.

In coastal regions such as Hung Yen and Ninh Binh, skies were occasionally sunny before the storm arrived. Later, strong winds, heavy rains, and high waves developed as the storm made landfall.

Lam noted that Storm No. 3’s rainclouds were concentrated in the southern quadrant of the system. Therefore, even after the storm's center moved inland, its circulation continued to generate very heavy rain in southern provinces like Thanh Hoa and Nghe An. Rainfall in these areas could reach 150–300 mm through the evening, or even higher.

Meanwhile, in the northern portion of the storm’s circulation - such as Hanoi and the Northeast - the rainfall had already eased compared to July 21. Rain continues intermittently in these areas, with light rain alternating with dry spells or no rain at all for several hours.

To determine whether rain or thunderstorms are expected in their area, Lam recommends that residents consult the radar weather maps on https://iweather.gov.vn/. On the radar, areas with strong convective clouds, heavy rain, and lightning appear in orange or red. Gray or black zones show little to no radar reflection, indicating sunny or overcast skies. Light and moderate rain appear in green or light green shades.

Importantly, the current radar system updates data every 10 minutes, enabling near real-time tracking. In addition to rain radar, satellite data shows lightning activity over the past hour - an important factor in identifying dangerous storm areas, including tornadoes or lightning strikes.

PV