An avoidable tragedy: Mal Bazar (05Oct2022) 8pm

Mal Bazar is now a large town in Jalpaiguri district in the Dooars (see map above). The Dooars mainly consists of tea growing areas which are dissected by numerous small rivers originating in the foothills of Kalimpong district in W Bengal (India) and Bhutan, the two major ones being Jaldhaka and the Torsa rivers.
The foothills on the northern borders receive some of the heaviest rainfall in this region (approx 4000mm annually), often in violent thunderstorms in the late evening and night.

On 05Oct2022 at around 8pm, after completion of Durga Puja in Mal Bazar, the idols were taken by the worshipers for the immersion ceremony to Mal river. What followed still seems rather blurry and confused, but many people were swept away as can be seen in the video
- 8 people died.

video credit: State IAG WhatsApp group

The 24hr (0830am to 0830am) rainfall record (in mm) of Gorubathan and Jaldhaka , both small hamlets in the catchment area (see map) where STH has manual rain gauges are given below:

My personal assessment is,

• At this time, the rivers of this area are fast flowing mountain streams fed by rainfall in the catchment area in the foothills.
• Having said that, I don't think the rainfall for the past three days could have triggered a 'flash flood'. There are no dams in the area.
  
• More likely, that they underestimated the current and in the ensuing panic people lost balance and drowned.
  

A media report is placed below:

And of course the politicians have stepped in to give their expert opinions:

 Update

Praful Rao
Kalimpong district
Darjeeling-Sikkim Himalaya

Rainfall data of Sep 2022 of some town in the Darjeeling - Sikkim Himalaya

 

We had deficient rainfall again for most towns with the notable exception of Mangan in N Sikkim.
Kalimpong was the most deficient receiving only 35% of its monthly rainfall. Interestingly, much of Kalimpong district is bang opposite SOUTH SIKKIM district and is separated only by the Teesta river. South Sikkim is the drought prone district of Sikkim ( -21% deficiency) as such rainfall deficiency in Kalimpong may be expected.
A number of low pressure areas formed in the Bay of Bengal during Sep2022 and that could be the reason for less rain in our region (the moisture bearing winds are drawn away from the sub - Himalayas when a circulation forms in the Bay).

Update from 'The Weather Channel' on 11Oct2022
Meanwhile, the southwest monsoon continues to withdraw from the northwestern parts of the country. Normally, its exit from the northeastern region begins around October 10; but judging from the rate of withdrawal thus far, it may get slightly delayed this year.

As for the seasonal precipitation, the northeastern region collectively recorded below-average rainfall during the four monsoon months from June to September. The combined monsoon rain figure for East and Northeast India stands at 1124.8 mm — 18% below their long-period monsoon average of 1367.3 mm.

Within the Northeast, the Assam-Meghalaya subdivision recorded 1600.7 mm rain (9% deficit), the N.M.M.T. states registered 943.2 mm precipitation (28% deficit), Arunachal Pradesh received 1430.3 mm (15% deficit), while Sub-Himalayan West Bengal and Sikkim enjoyed precisely ‘normal’ seasonal rains at 1887.1 mm.

Praful Rao
Kalimpong district
Darjeeling Sikkim Himalaya