The latest report from the weather agency showed that upper-air wind convergence zone at 5,000 meters above surface appeared in the Northern mountainous area this morning.
It is expected that medium- heavy downpours will hit the whole Northern provinces from tonight, notably risks of torrential rain, whirlwind, lightning, cyclone, hail and flash flooding in the Northwestern provinces of Ha Giang, Tuyen Quang, Lao Cai, Yen Bai, Lai Chau and Dien Bien.
Meanwhile, the South- Central, Central Highlands and Southern regions are warned rainy weather and thunderstorms on the large scale.
