This post may contain affiliate links. If you purchase through them, I may earn a small commission at no extra cost to you. Thanks for supporting our small business.
Gangtok sits at 1,650 meters (5,410 ft) on a ridge in the eastern Himalaya and is the capital of Sikkim, India. The city has a monsoon-influenced subtropical highland climate, which keeps daytime temperatures between 12 and 22°C (54 to 72°F) all year and dumps about 3,600 mm of rain annually, most of it between May and September. Because of the altitude, nights are cool even in summer, and the weather can shift from clear sun to heavy rain within a couple of hours during the monsoon.
Gangtok Weather by Month: Climate Overview
Gangtok’s average high ranges from 12.3°C (54°F) in January to 22.4°C (72°F) in August, while average lows run from 4.0°C (39°F) in January to 16.5°C (62°F) in July. The annual rainfall of about 3,626 mm falls across roughly 160 to 200 rainy days, with July alone recording about 650 mm. The driest stretch is November through February, when monthly totals drop below 80 mm. For help deciding when to plan a trip, see our best time to visit Gangtok guide.
Gangtok Weather by Month: Monthly Temperature and Rainfall Data
| Month | Avg High | Avg Low | Rainfall |
|---|---|---|---|
| January | 12.3°C (54°F) | 4.0°C (39°F) | 30.9 mm |
| February | 13.7°C (57°F) | 5.2°C (41°F) | 79.1 mm |
| March | 18.3°C (65°F) | 8.7°C (48°F) | 116.0 mm |
| April | 20.9°C (70°F) | 11.3°C (52°F) | 289.2 mm |
| May | 21.6°C (71°F) | 13.4°C (56°F) | 552.6 mm |
| June | 22.2°C (72°F) | 15.9°C (61°F) | 603.1 mm |
| July | 22.0°C (72°F) | 16.5°C (62°F) | 649.6 mm |
| August | 22.4°C (72°F) | 16.4°C (62°F) | 574.0 mm |
| September | 21.6°C (71°F) | 15.3°C (60°F) | 487.7 mm |
| October | 20.7°C (69°F) | 12.1°C (54°F) | 181.1 mm |
| November | 17.6°C (64°F) | 8.5°C (47°F) | 40.0 mm |
| December | 14.1°C (57°F) | 5.4°C (42°F) | 22.7 mm |
These are long-term monthly averages recorded in Gangtok. July is the wettest month at about 650 mm, and December is the driest at about 23 mm. The single biggest variable from one year to the next is the monsoon’s timing, which can start a week early or late.
Gangtok Weather by Month: Winter (December to February)
December through February is the coolest and clearest season. Days reach 12 to 14°C (54 to 57°F) and nights fall to 4 to 5°C (39 to 41°F), with occasional frost in the outskirts and snowfall at higher passes like Nathu La. Rainfall is light at 23 to 79 mm a month, and skies are often bright, which gives the clearest views of the Kanchenjunga range. This is the season for the Losoong and Losar festivals and for crisp, dry sightseeing, though you will need a heavy jacket after dark.
Gangtok Weather by Month: Spring and Pre-Monsoon (March to May)
March to May warms steadily, with highs climbing from 18.3°C (65°F) in March to 21.6°C (71°F) in May. Rain also builds fast, from 116 mm in March to 289 mm in April and 553 mm in May as pre-monsoon thunderstorms arrive. March and early April are the best of this window: warm, mostly dry, and full of blooming rhododendrons, which is why the flower exhibitions and garden walks are at their best then. By late May the monsoon is close, so pack a rain layer.
Gangtok Weather by Month: Monsoon (June to September)
June through September is the monsoon, delivering about 2,300 mm of the annual total, peaking at 650 mm in July. Rain falls as heavy, sustained downpours rather than quick showers, and humidity sits between 80 and 90%. Landslides on the winding mountain roads are a real risk and can close the route to the airport for hours or days. This is the wettest time to avoid if you want outdoor sightseeing, and our travel tips and FAQ article covers how to handle road closures. The one upside is that the landscape turns intensely green and waterfalls like Banjhakri run full.
Gangtok Weather by Month: Autumn (October to November)
October and November are the post-monsoon payoff. Rain drops to 181 mm in October and 40 mm in November, humidity falls below 70%, and the air is washed clear, giving the sharpest mountain views of the year. Daytime highs sit at 17.6 to 20.7°C (64 to 69°F) and nights cool to 8.5 to 12°C (47 to 54°F). This is the top season for trekking and for the viewpoint and monastery day trips around town, and it aligns with the Dasain holiday crowds, so book lodging early.
Gangtok Weather by Month: Humidity and Sunshine
Relative humidity runs about 50 to 60% in the dry winter months and 80 to 90% during the monsoon. Gangtok receives roughly 1,265 hours of sunshine a year, with December the sunniest month at about 174 hours and July the dullest at about 16 hours. Even on cloudy monsoon days the high altitude means strong UV, so sunscreen is worth using year-round. If you are weighing where to base yourself, the where to stay in Gangtok guide breaks down which areas sit above the cloud line.
