NEW DELHI: Bihar and eastern Uttar Pradesh, which saw over 100 deaths due to lightning in a single day on Thursday, continue to be under similar threat as
the India Meteorological Department
(IMD) on Friday predicted thunderstorms accompanied with lightning in both the states and Jharkhand during next 4-5 days.
Extremely heavy Monsoon rainfall is also predicted for isolated places in Bihar till Monday.
The southwest Monsoon, meanwhile, covered the entire country on Friday -- 12 days ahead of its
of July 8.
In the recent past, such early coverage of southwest Monsoon over the entire country occurred in 2013 when it had covered extreme north-western part of India on June 16 – almost a month ahead of then normal date of July 15.
The year 2013 had incidentally seen extremely heavy rainfall, cloud burst and flash floods in Uttarakhand on June 16-17, leading to massive destruction and casualties of human lives. There is, however, not such prediction, so far, this year for the Himalayan region.
Referring to the current Monsoon season, the IMD chief Mrutyunjay Mohapatra said the formation of a low pressure area over Bay of Bengal which moved west-northwest-wards and another cyclonic circulation over central India basically helped in advance of monsoon.
“The rain so far has been quite good and well distributed with 31 out of 36 meteorological subdivisions getting normal to large excess rainfall during June. It is quite beneficial for farmers," said Mohapatra.
The country has received rainfall of 155.2 mm against the normal of 128.2 mm during June 1-25. There has, accordingly, been satisfactory progress of sowing area coverage under Kharif (summer sown) crops. Acreages of all Kharif crops - paddy, pulses, coarse cereals, oilseeds, sugarcane, cotton and jute - are higher this year compared to the corresponding period of 2019.
Though the current progress of Monsoon rainfall is quite beneficial for ongoing sowing operations in the country, heavy rains in the past few days have put Bihar, Assam and other north-eastern states under threat of floods.
Lightning and thunderstorms had last year claimed over 380 lives across the country. Of these, the highest 125 casualties were reported from Jharkhand followed by 73 in Bihar.
Bihar had, in fact, suffered the most in terms of human casualties due to heavy rains and floods in 2019. Floods had claimed 850 lives in the country during pre-Monsoon, Monsoon and post-Monsoon seasons last year. Of these, the highest casualties of 306 were reported from Bihar followed by 136 from Maharashtra, 107 from Uttar Pradesh and 88 from
On progress of 2020 Monsoon while referring to new onset and advance dates, released last month, the IMD said there has been normal progress over south and east India, about a week delay advance over northeast India and about 7-12 days early advance over central and northwest India.
As per the revised normal arrival dates, the monsoon sets over Kerala around June 1, nearly same as the old normal date and covers the entire country by July 8 — one week before the old normal date (July 15).
Under revised reference dates for withdrawal, Monsoon withdrawal from northwest India will be delayed by more than two weeks (September 17) compared to the old normal date (September 1).
“Monsoon retreats from most parts of the country except south Peninsula and some parts of neighbouring central India by October 15, coinciding with the existing (old) normal and subsequently northeast monsoon gets established over south Peninsula,” said the IMD in its report on revised reference dates of onset, progress and withdrawal of Monsoon over India, released on May 15.
The new normal withdrawal dates of monsoon as per the operational data of recent years is delayed compared to the old normal in most parts of the country except few grids over northeast part of the Peninsula where the monsoon withdrawal in the new normal is early by 1-3 days.
“Significant delay was observed in the new normal monsoon withdrawal over extreme northwest India (11-16 days), west central India (4-10 days), northwest Peninsula (7-12 days), north India (3-7 days) and northeast (5-8 days). Over other areas, the delay in the new normal is 1-3 days indicating close match with the existing (old) normal,” said the IMD.
As per new reference dates, the monsoon arrival is now two days early in Delhi (June 27 instead of June 29), three days late in Coimbatore (June 5 instead of June 2) and one day late in Mumbai (June 11 instead of June 10). The Monsoon will be six days late in Chandigarh (June 28 instead of June 22) while it will be seven days early in Jammu (June 28 instead of July 5).
Comparison of new and revised arrival and withdrawal dates of Delhi shows that the withdrawal will four days late (September 25 instead of September 21). This would mean monsoon in the Capital would technically be six days longer.
Similarly in Mumbai, the monsoon period will be eight days longer as it will arrive a day late (June 11 instead of June 10) but withdraw by nine days late (October 8 instead of September 29).
These changes are based on analysis of historical data on changing rainfall patterns across the country. While the normal dates of onset are revised based on data during 1961-2019, dates of withdrawal are revised based on data during 1971-2019. The old normal monsoon onset and withdrawal dates were based on data during 1901-1940.