On Tuesday, Tropical Storm Etau storm was moving west over central Vietnam, where five airports in its path have been closed.
Winds of up to 65kph are expected to weaken to a tropical depression once the storm reaches Cambodia and Thailand, but farmers in lower Isaan have been warned to prepare for crop damage.
The department said 36 provinces have suffered flash floods and landslides since October 7, damaging a total of 92,085 households in 2,493 villages.