The unexpected weather condition was due to an influence of a low pressure trough.
The peak rainfall doused the mountainous provinces of Thai Nguyen, Bac Giang, Cao Bang, Tuyen Quang, Yen Bai and Bac Ninh.
As reported, the excessive downpour resulted in large-scale serious flooding and power outage in many streets of Thai Nguyen province.
The heavy rain made large- scale power outage in Yen Bai province.
According to the National Hydrology Meteorology Forecast Center, heavy to heavy downpours doused the Northern mountainous region with an average rainfall of 109- 232 mm.
The low pressure trough in combination with upper-air wind convergence zone at 1500-5000 meters above the ground is expected to result in flooding downpour across Lai Chau, Dien Bien, Hoa Binh, Son La, Cao Bang, Lang Son, Quang Ninh, Ha Giang, Tuyen Quang, Bac Kan, Phu Tho, Vinh Phuc and Thai Nguyen until this weekend.