Why does Bach Ma peak in Hue have up to 1,740mm of rain in one day?

(Dan Tri) - Bach Ma is one of the heaviest rain centers in Vietnam, not only in this heavy rain but also in other heavy rains, Bach Ma is always one of the rain centers of Hue as well as the whole country.

The National Center for Hydro-Meteorological Forecasting said that from the morning of October 28 to the end of the night of October 29, the area from South Quang Tri to Da Nang and the East of Quang Ngai province will have heavy to very heavy rain with common rainfall in South Quang Tri and the East of Quang Ngai province of 150-300mm, locally over 500mm.

Forecast for Hue and Da Nang areas is that there will be widespread rain of 200-400mm, locally over 600mm. The area from Ha Tinh to Northern Quang Tri will have moderate rain, heavy rain and thunderstorms with widespread rainfall of 80-150mm, locally over 300mm.

In addition, according to the hydrometeorological agency, on the day and night of January 28, the Central Highlands, the South and the eastern provinces from Gia Lai to Lam Dong will have rain, moderate rain and thunderstorms with rainfall of 20-40mm, locally heavy to very heavy rain of over 100mm.

Many places in Hue have been submerged in water in recent days (Photo: Vi Thao).

Speaking to Dan Tri reporter , Mr. Mai Van Khiem, Director of the National Center for Hydro-Meteorological Forecasting, said that according to general regulations on hydro-meteorological monitoring and reporting regime, daily rainfall is calculated in the period from 7:00 p.m. the previous day to 7:00 p.m. the following day.

This is a unified convention in the monitoring system to ensure continuity and synchronization of data serving disaster forecasting and warning, according to Mr. Khiem.

The expert said that statistical data from the national hydrometeorological monitoring network showed that the five largest daily rainfall values ​​were as follows:

Hue Meteorological Station (Hue) is 997.6mm (November 3, 1999); Nam Dong Meteorological Station (Hue) is 927.3mm (November 11, 2007); Hue Meteorological Station is 863.7mm (November 2, 1999); Tra My Meteorological Station (Da Nang) is 782.4mm (November 5, 2017) and A Luoi Meteorological Station (Hue) is 758.1mm (November 2, 1999).

During the recent rainy season, the above meteorological stations recorded the following rainfall amounts:

Hue meteorological station is 206mm (October 24); Nam Dong meteorological station is 968.1mm (October 27), exceeding the previous historical value; A Luoi meteorological station is 390.2mm (October 27); Tra My meteorological station is 430.6mm (October 27).

According to Mr. Khiem, also during this rain, at the automatic measuring station at Bach Ma peak (Hue), the highest rainfall observed in one day was 1,740mm (October 27). This automatic station has only been put into operation for monitoring in recent years.

Mr. Khiem said the above figures show that the Central Central region, especially Hue and Da Nang, continue to record heavy rains.

According to the expert, Bach Ma is one of the heaviest rain centers in Vietnam. Not only during this heavy rain period, Bach Ma has sudden rain, but during other heavy rain periods, Bach Ma is always one of the rain centers of Hue as well as the whole country.

Mr. Khiem said the main reason was due to terrain factors. Bach Ma point is located in the Truong Son range, right on the edge of the East Sea, at an altitude of over 1,400m.

"When the humid air mass from the sea blows in (especially when there is a weather combination of low-level cold air, tropical convergence zone and humid easterly wind zone above active) creating a humid convergence zone, then there is forced lifting of the terrain - that is, the moisture converges and rises high, causing the moisture to condense strongly, creating very heavy rain in the area," Mr. Khiem informed.

The expert said that according to monitoring data, the rainfall in Bach Ma is often much higher than in neighboring areas and the rainfall in Bach Ma always reaches extreme values ​​higher than the rain gauges in Hue or Da Nang.

Dantri.com.vn

Source: https://dantri.com.vn/thoi-su/vi-sao-dinh-bach-ma-o-hue-co-luong-mua-lon-toi-1740mm-trong-1-ngay-20251028123524102.htm