The India Meteorological Department (IMD) has predicted that the southwest monsoon will remain here till October 1. There is no chance of start of withdrawal of monsoon till October 1 due to the passage of western disturbance and the formation of a potential depression and low pressure area in Bay of Bengal caused by the erstwhile Pacific super typhoon Mangkhut. Both the systems are likely to infuse a fresh surge of monsoon.
The official date for the commencement of withdrawal of southwest monsoon is September 1.
The prolonged stay of monsoon season may sound as good news, but it comes with some repercussions. “The delay in the withdrawal of monsoon will further delay the onset of the next season. The delay will also push forward the onset of winter. And with El Nino all set to make appearance by the end of the year, it may impact the upcoming season, which turn mild due to all these factors,” IMD officials said.
Private weather forecaster Skymet too predicted that southwest monsoon will prolong its stay at least till September end.
Due to this, low pressure and depression over the Bay of Bengal from east to northwest India are likely to record moderate to heavy showers. A few areas might see some heavy downpour. Besides this, monsoon will also revive along the West Coast and Mumbai, which has been dry for last many days.
Officials said southwest monsoon is primarily governed by low pressure and depression.
The IMD said a preparatory cyclonic circulation sent in from the West Pacific lies over the central Bay of Bengal and neighbourhood. As a result, rain will start lashing coastal parts of Odisha, Madhya Pradesh and adjoining Andhra Pradesh by September 20 and 21; Chhattisgarh & Telangana on September 20 and 21; over Madhya Pradesh on September 21 and 22, and over parts of northwest India on September 22 and 23. East Rajasthan and north India will receive rainfall on September 23 and 24.
The US National Weather Services agency said depression would erupt in intensely heavy precipitation over North-West India: South Rajasthan, West Madhya Pradesh, East and North Gujarat, Delhi and West UP. This is likely to pan out over the next 12 to 15 days.
As per IMD data, monsoon withdrawal was most delayed in 2017 and had begun on September 27. In 2016, monsoon withdrew on September 15. Monsoon withdrew on September 4 in 2015 while in 2014 it withdrew on September 23. Monsoon withdrawal saw on September 9 in 2013 while it had withdrew on September 24 on 2012. Prevalence of dry weather for five straight days and reduction in moisture content are among the main factors considered for announcing monsoon’s withdrawal. Another condition is the setting of anti-cyclonic circulation over western Rajasthan. Agriculturists said the late retreat is not a cause for worry as rains aren’t heavy now and hence would help paddy, cotton and coarse cereals, though crops ready for harvesting may face some damage.
Presently, rainfall deficiency is over 10 per cent till September 19. The monthly deficit has increased from 5 per cent in June, to 5.8 in July and 7.6 in August. The country witnessed 750.5 mm rainfall as against the normal of 834.5 mm till date.
Out of total 36 sub-divisions, as many as 26 have witnessed normal rains, while nine continue to remain rain-deficient and only Kerala has recorded excess rain. Despite deficiency the sowing of paddy has been carried out over an area of 1,053 lakh hectare (lh) as against 1,046 lakh hectare covered in the corresponding week last year. Rice, oilseeds and sugarcane have reported a jump in acreage, while the planting of pulses and cotton is marginally lower. At 383 lakh hectare, rice planting is 2.28 per cent higher than that reported in the same week last year.

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