Although there are many rivers and streams the most important rivers are Tlawng, Tut (Gutur), Tuirial (Sonai) and Tuivawl. These rivers flow through the northern territory and eventually join river Barak in Cachar. The Koldoyne (Chhimtuipui), which originates in Myanmar, is an important river in the south Mizoram. It has four tributaries and the river is in patches. The Western part is drained by Karnaphuli (Khawthlang tuipui) and its tributaries. A number of important towns are situated at the mouth of the river.
Lakes are scattered all over the state. The most lakes are Palak, Tamdil, Rungdil; and Rengdil.
Mizoram gets an average rainfall of about 3,000 mm with Aizawal town having 2,380 mm and Lunglei 3,178 mm. During rains the climate in the lower hills is humid. Rainfall is evenly distributed. Heavy rains start in June and continue upto August. The crops hardly ever suffer from drought. In the lower areas malarial fever is a common feature after rains. Even during the hot season, it is cool and pleasant on the higher hills. The special feature of the climate here is the occurrence of violent storms during March-April. Heavy storms sweep the hills in the entire state.
Temperature in the state varies from about 12o C in winter to about 30oC in summer. Winter is from November to February and during this season there is no rain or very little rain. Winter is followed by springwhich starts at the end of February and continues till the middle of April. In April, storms occur and the summer starts. In April and May temperature usually goes up to 30oC.
A mist covers the hills. September and October are the autumn months and the temperature is usually between 19oC and 25oC.