Rainfall data of Jul2022 of some towns in the Darjeeling - Sikkim Himalaya

As per IMD, the southwesterly wind flow occurring over most parts of India and Indian Seas gives rise to southwest monsoon over India from June to September. The typical rainfall pattern over the Darjeeling-Sikkim Himalaya is shown below:

July is the month when our rainfall normally peaks, with the rains gradually decreasing thereafter.
The rainfall record of July2022 (day wise) of some towns of this region is  tabulated below:

You will notice that we have added rainfall data of
a. Mangzing (a remote village in Pokhriabong GP, Gorubathan block, Kalimpong district)
b. Bijanbari (Relling GP, Pulbazar block, Darjeeling district)
in our effort to map the rainfall of this region.
What is clearly evident is that the rainfall of July 2022 for many parts of the hilly regions of North Bengal and Sikkim was significantly below the normal monthly rainfall (615.8mm). Also for the first time in many years, Kalimpong rainfall exceeded that of Darjeeling.
What is also noticeable from the graph (Fig 1) is the towns mentioned had significantly higher rainfall in June than July which is an anomaly.

Fig1

July 2022 began with a large deficit in rainfall in the Sub Himalayan W Bengal and Sikkim regions however, the rains picked up a little in the third week of July. The paddy crop which is normally planted in July in rain flooded fields never happened in many places (Fig2).

 Fig 2

There was also very little activity in the Bay of Bengal and Pacific Ocean in this entire period  with hardly any typhoons forming in Pacific or low pressure areas in the Bay. A low which formed in Bay on 10July along with the rainfall deficiency is shown in Fig3:

 Fig3

Rainfall departures for July2022 for W Bengal and Sikkim are given below (Fig4)

Fig4

Rainfall was also deficient in South Bengal (Fig5)

 

 (Fig5)

Despite the deficit in rainfall, there were landslides especially along roads and NH10

Landslide at Reshi checkpost on NH717A (below Pedong (Kalimpong district) on 25July 2022.

Shreya Gurung
&
Praful Rao

Kalimpong district
Darjeeling Sikkim Himalaya

Rainfall data of some towns in Darjeeling - Sikkim Himalaya - May2020

The major weather event of May2020 was of course Super Cyclone 'Amphan' (see above). Much more on the storm is covered in earlier posts.

Rainfall data of Sikkim is from IMD Sikkim.

Grateful thanks to Shreya for helping out.

Praful Rao,
Kalimpong district,
Darjeeling - Sikkim Himalaya

Cumulative rainfall data of Darjeeling-Sikkim Himalaya (01Oct2019 to 30Dec2019)

Source: mausam.imd.gov.in

Praful Rao
Kalimpong district
Darjeeling-Sikkim Himalaya

Rainfall data of Darjeeling-Sikkim Himalaya (Post Monsoons 2018 and Winter 2019)

Post-Monsoon (Oct-Dec2018)
During the post -monsoon period (2018), there was an almost abrupt halt in the rains in Darjeeling-Sikkim - with the exception of North Sikkim.

Our records:

Oct 2018 rainfall
Kalimpong: 16.1mm
Mangan (North Sikkim): 157mm

Nov2018 rainfall 
Kalimpong: NIL
Mangan (North Sikkim): 61mm

Dec 2018 rainfall 
Kalimpong: 22.8mm
Mangan (North Sikkim): 16mm

Winter (Jan-Feb2019)

Jan2019
Kalimpong: NIL
Mangan (North Sikkim):19mm

Praful Rao,
Kalimpong district,
Darjeeling-Sikkim Himalaya

 

Rainfall data of March 2016 and our dying springs.

Though the rainfall maps (top) and the data (above) indicate that the shortfall in precipitation has decreased (from around 80% to 14%) in March 2016, this does not represent the facts on the ground where changing rainfall patterns have resulted in winter rains almost vanishing. So what we have these days is an alternating cycle of abundant rain (5 months in the monsoon period) followed by 6-7 bone dry months.

In this situation, Kalimpong town is today facing an acute potable water crisis - water from the Govt PHE source is supplied only to certain parts of town that too, once in 6 days. The rest of the town and all hotels, many schools and homes are forced to buy water.

But it is in the rural areas all over the Himalayas that a major problem is looming with many natural springs drying up. In Almorah (Uttarakhand) the number of natural springs has dwindled from 350 to 60 in the span of 150yrs.
Some of the obvious reasons for this decline, besides the changing rainfall patterns are:-

• Developmental activities in the mountains such as road construction and massive urbanization has resulted much of the rain water flowing off as surface run-off rather than percolating into the soil and recharging the aquifers.
• Declining forest cover again enhances surface run-off whereas vegetation would reduce run-off and augment aquifer recharge.

Recently, in Sikkim there has been a government intervention at springshed management which have shown positive results but we will have to wait for the long term benefits of this initiative. Elsewhere, villagers are left to fend for themselves as far as finding water sources are concerned and to check the extent of the problem STH carried out a survey in a rural area (Bhalukhop village) on the western face of the Kalimpong ridge line (see map below).

 My guide for the survey of the health of springs in Bhalukhop was Man Bahadur Darji, 57, a denizen of Rai Gaon, Bhalukhop. The results are placed below in images, with coordinates of the springs in each image:-

Praful Rao,
Kalimpong,
Dist Darjeeling

At last, welcome rains in the Darjeeling-Sikkim Himalaya : 30Mar2015

If March2015 was the wettest in the last 100yrs for much of North and Central India (see here), then it must have been one of the driest in the Darjeeling-Sikkim region (see Slide 1)
From Oct2014, when the SW monsoons receded from this area, till 30Mar2015 we had no significant rains leading to bone dry conditions which caused raging forest fires (Slide 2), a severe potable water crisis in most urban dwellings in the region and dust/smoke haze which lowered visibility and resulted in months of atmospheric obscurity.
On 30Mar2015, the same storm system (Slide 3) which caused flooding and 16 deaths in Kashmir, barreled its way towards the Darjeeling-Sikkim Himalaya, brought in sharp thundershowers at 4.40pm.
Rainfall data for 4 places in this region is placed below :-
Kalimpong - 22mm
Darjeeling town - 17mm
Aap Botey(Mineral Springs- Darjeeling) - 20.2mm
Mangan (N Sikkim) - 37mm

Praful Rao,
Kalimpong,
Darjeeling district.

Rainfall data July 2014 and associated landslide activity.

Deficient rainfall in the Darjeeling-Sikkim Himalaya

As can be seen from the rainfall data of some stations of the region (slide -1) there was an overall deficiency in the amount of rainfall in the month of Jul2014. The monsoon rainfall normally peaks in July (see here) before starting to decline in Aug/Sep and withdrawing from the sub-continent in Oct.
However, in 2014 rainfall in Kalimpong was almost 40% deficient resulting in inability by farmers to plant the full paddy crop this year in some parts of Pudung village (Kalimpong). All other stations also show decline in rainfall in 2014 to varying degrees.
This is in keeping with the data obtained from IMD in slide -2 (see details here).

Landslide activity

• No major landslides and no deaths due to landslides in Darjeeling or Sikkim in July2014.
• Malin village in Maharastra, India - 151deaths due to landslide on 30Jul2014. 
• Pangla, on Dharchula-Kailash Mansarovar yatra, in Pithoragarh district - 5 deaths on 27July2014
  
  Praful Rao,
  Kalimpong,
  Dist Darjeeling

From the Telegraph today

From 'The Telegraph' today.

Weather data show that the shortage of rain is as high as 800mm at some places in the region compared to previous year’s figures.

While Jalpaiguri received 2,170mm rain from January 1 to July 25 in 2013, this year’s recording for the same period was 1,881mm, a shortage of 289mm.

The difference in the rainfall in Alipurduar is 835mm with the town receiving 2,238mm from January to July 25, 2013, and 1,403mm this year. The figures for the same period in 2013 and 2014 in Banarhat are 3,481mm and 2,645mm, respectively.

Since the last 15 days, Siliguri and Jalpaiguri have not got heavy rainfall. 

Read full article here

STH stormwatch 
IMetD is reporting a low pressure in the northwest Bay of Bengal which is expected to move in a northwesterly direction.
We are keeping a watch.

Praful Rao,
Kalimpong
Dist Darjeeling

Rainfall data Darjeeling district and Sikkim: August 2013

August 2013 saw a flurry of activity in the Bay of Bengal with a number of low pressures forming. The low pressure reported just south of Kolkata by IMetD on 19Aug2013 caused moisture bearing clouds to move towards the Darjeeling Sikkim Himalaya resulting in the "Hurricane" in Darjeeling between 22:00 hrs and 00:00 hrs that night.

Strangely, even though the bay was swamped by low pressure systems in August 2013 , the Darjeeling Sikkim Himalaya and most of the North East still remained deficient in rain. Most of the low pressures that formed traced a North Westerly path giving excessive rain to most of central India and Rajasthan (shown above). 

No fatalities were caused by landslides in August 2013

September is when the SW monsoon slowly retreats from the Indian sub-continent, nonetheless from this month onwards STH will also include rainfall data from Siliguri and a few other stations in our monthly rainfall report for those interested in the hydrology of this area.   

Rohan Rao,

Kalimpong,

Dist-Darjeeling,

Email-rohan.rao1313@gmail.com

Rainfall data Darjeeling district and N Sikkim - Jun2013

Jun2013 was extraordinary; it was the month of the "Himalayan Tsunami" when torrential rains over Uttarakhand and Himachal Pradesh in mid Jun2013, caused unprecedented loss of life and a disaster which the country is still trying to grapple with.
Whilst the rest of the country reported normal to excess rainfall, the north eastern states of India went deficient in rainfall. STH reported the formation of two low pressure areas in the Bay of Bengal, the first weather system eventually reaching the Uttarakhand region in mid Jun2013.
Also, two interesting facts observed in Jun2013 were :-

• The 24hr rainfall over Dehradun on 17Jun2013 (338mm) was more than the entire month's rainfall in Kalimpong for Jun2013.
• In the Darjeeling -Sikkim area, approximately half the month of June2013 was almost dry (less than 5mm rainfall).
  
  
  Praful Rao,
  Kalimpong,
  Dist Darjeeling.
  
  
  
  

The good and bad news : El Nino is around.

 

It is now official that El Nino conditions will prevail over the the northern hemisphere at least until Nov2012 and it is widely speculated that this will lead to a shortfall in rainfall in India even as the south westerly monsoon slowly withdraws from the sub-continent.

As if to prove this point, we are experiencing extraordinary weather in this part of world with rainfall again running woefully short in Aug2012 (we had deficient rain in May & Jun2012) and with no major weather system (ie formation of low pressure/depression or cyclone) developing in the Bay of Bengal thus far in 2012.
Whereas this maybe good news as regards landslides in this region (we had no major landslides or casualties except for the Tindharia and Pagla Jhora slides), I shudder to think of what it portends for our drinking water and power situation in the summer of 2013 (not to mention impact on agri/horticulture over the winter months etc).

Praful Rao


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