Experts explain the cause of heavy rain in the Central region

In 24 hours (from October 26-27), Bach Ma (Hue) recorded a record rainfall of more than 1,600mm, becoming the place with the largest daily rainfall (total rainfall falling at a location in a day) in Vietnam's history.

According to Mr. Mai Van Khiem, Director of the National Center for Hydro-Meteorological Forecasting, many places in Hue City, Da Nang City and some central provinces have had very heavy rain.

Rainfall from 7am on October 27 to 3am this morning (October 28) was locally over 440mm in some places, such as: Bach Ma Peak Station (Hue City) 994.2mm; Trung Loc Lake Headquarter Station (Da Nang City) 473.4mm; Ba Dien Station ( Quang Ngai ) 442.2mm.

On the evening of October 27, flood from upstream poured into Ta Trach river, causing the foot of Le No bridge in Khe Tre commune ( Hue city) to collapse.

Previously, in 24 hours (from October 26-27), Bach Ma recorded a record rainfall of more than 1,600mm, becoming the place with the largest daily rainfall in Vietnam's history. Within a day and a half, from the night of October 25 to the morning of October 27, the accumulated rainfall here reached 2,272mm. Also in the past 24 hours, at Nam Dong monitoring station, the rainfall reached 1,065mm, far exceeding the historical value in 1999.

At the same time, many places in Hue City and Da Nang experienced major floods, with rivers exceeding alert level 3. In particular, at Phu Oc station (Hue), on the afternoon of October 27, the flood level exceeded the 2020 record.

The Director of the National Center for Hydro-Meteorological Forecasting said that the cause of this exceptionally heavy rain was due to a combination of low-level cold air, a tropical convergence zone lifting its axis from the South, combined with strong humid East winds at an altitude of 1,500-5,000m. This is a typical situation causing prolonged heavy rain in the Central region.

It is forecasted that from this morning to tomorrow night (October 29), in the area from South Quang Tri to Da Nang City and the East of Quang Ngai province, there will continue to be heavy to very heavy rain.

Rainfall in South Quang Tri and East Quang Ngai province is generally 150-300mm, locally over 500mm; Hue city and Da Nang city generally 200-400mm, locally over 600mm; the area from Ha Tinh to North Quang Tri has moderate rain, heavy rain and thunderstorms with common rainfall of 80-150mm, locally over 300mm.

Then, on October 30, in the area from Ha Tinh to Da Nang City and the East of Quang Ngai Province, there was still moderate rain, heavy rain and thunderstorms with common rainfall of 30-70mm, locally very heavy rain over 100mm. From the night of October 30, heavy rain tended to decrease in the South and gradually move up to the North Central region. Continuous heavy rain increased the risk of flooding, flash floods and landslides in the Central region.

“In addition to the risk of flooding in Hue City and Da Nang, we would like to emphasize the very high risk of flash floods and landslides in all mountainous areas in the western part of the Central region, with a level 3 disaster risk warning - the highest level for flash floods and landslides,” said Mr. Khiem.

In addition, today and tonight, in the Central Highlands, the South and the East of the provinces from Gia Lai to Lam Dong, there will be rain, moderate rain and thunderstorms with rainfall of 20-40mm, locally heavy to very heavy rain over 100mm. During thunderstorms, there is a possibility of tornadoes, lightning, hail and strong gusts of wind. Warning of the risk of heavy rain (>80mm/3h).

Forecasting that by the end of 2025, Mr. Khiem said, around the first half of December, the Central region is still likely to experience many periods of moderate and heavy rain, mainly concentrated from Ha Tinh to Da Nang, Khanh Hoa and the eastern region of the provinces from Quang Ngai to Dak Lak.

In November, rainfall in most areas across the country was 10-30% higher than the average of many years, and in some places higher; in the North, it was approximately average, except for the northern mountainous region where rainfall tended to be 10-20% less.

Natural disasters are still complicated and unpredictable. Authorities and people need to closely monitor official weather reports on floods, landslides, etc. to have appropriate response plans to ensure safety for people and property.

Source: https://cand.com.vn/doi-song/chuyen-gia-ly-giai-nguyen-nhan-dot-mua-lon-tai-mien-trung-i786103/