According to the National Center for Hydro-Meteorological Forecasting, from the night of June 28 to July 1, the mountainous and midland regions of Northern Vietnam are expected to experience moderate to heavy rain, with localized areas receiving very heavy rainfall exceeding 300mm.

As of the morning of June 28, regions in Northern Vietnam have already recorded significant rainfall, with some areas like La Hiên in Thái Nguyên measuring 187mm, Hồ Ngòi Là in Tuyên Quang at 120.6mm, and Bố Hạ in Bắc Ninh at 107mm. The forecast for June 28 indicates scattered showers and thunderstorms, with rainfall amounts ranging from 10 to 30mm, and isolated areas may see over 60mm.

From the night of June 28 to June 30, the mountainous and midland regions are likely to see rainfall of 50 to 120mm, with some areas exceeding 300mm. A warning has been issued for the potential of heavy rain with amounts over 100mm within three hours. On the night of June 30 and into July 1, heavy rain is expected to continue, with typical amounts of 30 to 60mm per 24 hours, and isolated areas may exceed 100mm.

The lowland areas of Northern Vietnam will also see rain starting tonight, with expected rainfall of 15 to 30mm, and some areas may receive over 70mm. In the Central Highlands and Southern Vietnam, scattered showers and thunderstorms are forecasted for the evening and night of June 28, with rainfall amounts of 10 to 30mm, and isolated areas may see heavy rain exceeding 60mm.

There is a risk of thunderstorms, hail, and strong winds during these rain events, with a disaster risk level of 1 due to heavy rain, thunderstorms, and hail. Currently, water levels in the Thao River are fluctuating, and some rivers in Tuyên Quang, Lạng Sơn, and Thái Nguyên are rising. A flood warning has been issued for small rivers in Northern Vietnam, with expected flood levels rising by 2 to 4 meters.

There is a high risk of flash floods and landslides in mountainous and midland provinces. The disaster risk level for flooding is also classified as level 1, with potential flooding in low-lying areas along rivers affecting transportation, aquaculture, agriculture, and socio-economic activities.