Climate

Sikkims geographical location with its altitudinal variation allows it to have tropical, temperate and alpine climatic conditions within its small area of 7,096 kms.

Temperature conditions vary from sub-tropical in the southern lower parts to cold deserts in the snowy north. It is also the most humid region in the whole range of the Himalayas, because of its proximity to the Bay of Bengal and direct exposure to Southern monsoon. 

Rainfall is heavy and well distributed during the months from May to early October. July is the wettest month in most of the places. The intensity of rainfall during South-West monsoon season decreases from south to North, while the distribution of winter rainfall is in the opposite order. The highest annual rainfall for the individual station may exceed 5000 mm. and average number of rainy days (days with rain of 2.5 mm. or more) ranges from 100 at Thangu in north Sikkim to 184 at Gangtok in east Sikkim.

Fog is a common feature in the entire state from May to September.

Biting cold is experienced at higher altitudes of 10,000 ft plus. The temperature rarely rises above 15 degree centigrade and heavy snowfall occurs during the winter months. Some also receive snowfall during April or mid-November.

1. Cold Weather Season: December February
2. Spring Season: March May
3. South-West Monsoon: June September
4. Period of retreating Monsoon: October November