The maximum temperature on the following day will be 28C while at night the mercury will drop to 25C, according to the national weather agency.
From now until September 24, northern Vietnam can expect medium to heavy rains averaging from 40-80 millimetres, and even reaching 150 millimetres in some locales, due to the effect of a low atmospheric pressure combined with a convergence zone.
A warning of flash floods, landslides and localised flooding has been issued for mountainous provinces including Dien Bien, Lai Chau, Lao Cai, Yen Bai, Ha Giang, Cao Bang, Bac Kan, Thai Nguyen, Lang Son, Quang Ninh and Tuyen Quang.
The capital city is also expected to see scattered showers on September 22 and medium to heavy rains with thunderstorms over the next two days, during which there may be whirlwinds, lightning, hail and strong gusts.
