Gangtok: The impact of Cyclone Arnab, which has weakened into a low-pressure area, has brought rainfall and a sharp fall in temperatures across Sikkim, with Gangtok recording an 11.4-degree Celsius drop in its maximum temperature compared to October 28. The India Meteorological Department (IMD) has forecast further rainfall across the state over the next two days, with heavy rainfall possible at isolated places.
Debapriya Roy, Head of the India Meteorological Department (IMD), Gangtok, Sikkim, said the cyclone had weakened into a low-pressure area, but its residual circulation continued to influence weather conditions in the state.
“Rainfall is likely in Sikkim today and tomorrow, with heavy rainfall possible at one or two places today,” Roy said.
The impact of the weather system is evident in Gangtok’s temperature readings. On October 27, the town recorded a maximum temperature of 25.3°C and a minimum of 13.1°C. On October 28, the maximum temperature stood at 25.4°C and the minimum at 14.2°C.
The latest readings show a sharp decline, with Gangtok recording a maximum temperature of 14°C and a minimum of 12.4°C, along with 21.2 mm of rainfall. The maximum temperature has fallen by 11.4°C from the October 28 reading.
Yuksom recorded 60.8 mm of rainfall in the past 24 hours, indicating the intensity of the rainfall associated with the low-pressure system.
The latest IMD seasonal rainfall data for June 1 to September 30, 2026, shows that Sikkim received 1,761.7 mm of rainfall against the normal average of 1,672.9 mm, registering a 5 per cent excess. This marks a turnaround from the previous monsoon season, when the state received 1,514.4 mm against the same normal average, resulting in a 10 per cent rainfall deficit.
However, the state-level figures mask considerable variations in rainfall distribution across districts. Gyalshing recorded the highest excess rainfall in 2026 at 35 per cent, receiving 2,431.7 mm against its normal of 1,798.5 mm. Soreng recorded 17 per cent excess rainfall at 2,108 mm, followed by Namchi at 16 per cent with 1,948 mm.
Mangan recorded rainfall almost at its normal level, with 1,548.4 mm against the normal of 1,547.2 mm. Pakyong received 1,580.7 mm, registering a marginal 1 per cent deficit, while Gangtok recorded 1,992 mm, 8 per cent below its normal of 2,170 mm.
The district-wise comparison also highlights a significant recovery in rainfall in several parts of Sikkim compared to 2025. Gyalshing, which had recorded a 24 per cent deficit last year, registered 35 per cent excess this year. Soreng improved from a 36 per cent deficit in 2025 to 17 per cent excess in 2026. Namchi, which had recorded 47 per cent excess rainfall last year, received 16 per cent excess this year.
Roy said the overall monsoon performance this year had been relatively better than last year, with rainfall approximately 5 per cent above normal. He attributed the recent rainfall pattern partly to the influence of the cyclone.
Meanwhile, with further rainfall forecast, Roy advised residents, particularly those living in vulnerable areas, to remain cautious. People residing in kutcha houses and landslide-prone locations have been advised to take necessary precautions.