Unusual dry spell driving up deficit, discomfort: IMD
NEW DELHI: The second of the so-called break-monsoon phases has left the country with a 9% deficiency in total monsoon rainfall till August 16, although the India Meteorological Department expects rainfall to resume from later this week.
Meanwhile, the national capital, where it last rained on August 9, is unlikely to see a resumption till August 19 — making it among the longest break-monsoon phases the city has seen, IMD officials said. The result: high temperatures; for instance, Tuesday’s maximum, at 38 degrees Celsius was a full four degrees above normal. Delhi at present is receiving hot and dry winds from the northwest. This is also causing the temperatures to rise, Met officials said.
August has seen poor rain across India: a 33% overall deficiency in rainfall; a 51% deficiency over central India; a 22% deficiency over northwest India; a 37.7% deficiency over peninsular India; and a 5% deficiency over east and north-east India.
This has worsened the overall statistics too. Cumulative rainfall between June 1 and August 16 has seen a 9% deficiency over the entire country; 8% deficiency over north-west India; 11% deficiency over east and north-east India; and 13% deficiency over central India . Only the southern peninsula is in the green — with 5% excess rainfall.
Delhi has seen a 58% deficiency in rainfall in August and a 9% surplus overall (from June 1 to August 17).
To be sure, rainfall that is plus-or-minus 20% of the long period average is considered normal.
According to weather experts, break monsoon is a phase during the southwest monsoon when there is a break in the monsoon showers. This pause could last a couple of days, going up to a fortnight.
While rainfall decreases in parts of north, north-west and central India, this weather phenomenon results in an increase in showers along the Himalayan foothills, in north-east India and also along the southern peninsula.
Met officials added that this long dry spell is the primary reason behind Delhi witnessing high temperatures, which is unlikely for this time of the year.
“Over the last few years, we have seen that the break monsoon conditions usually last for five to six days—maximum for a week. This time, the period without rain is going to be around 10 days, which is a long time. This is causing temperatures to rise,” said Kuldeep Srivastava, head of IMD’S regional weather forecasting centre.
This is the second major break in this monsoon; the first one was between June 29 and July 11.
However, IMD officials expect monsoon rain to resume by Wednesday or Thursday. “There was a long break phase in July also. But now there is a new monsoon pulse over southern peninsula which will move upwards gradually. A low-pressure area which has formed over northwest Bay of Bengal will also bring rain in its path,” said DS Pai, senior scientist at IMD Pune.
“With the movement of the low pressure system, we are expecting rains to commence over central India, including Maharashtra, Madhya Pradesh, etc, and then over parts of northwest India from August 19. Easterly winds at lower levels have started picking up over some parts of north-west India,” said RK Jenamani, senior scientist, national weather forecasting centre, IMD.
It isn’t clear whether the revival will see the deficit being made up.
“Rains during the second half may help cover the rain deficiency during monsoon season,” said Pai but Mahesh Palawat, vice-president (meteorology and climate change) at Skymet Weather Services, a private weather forecasting agency, said the forecast only suggests moderate to light rain. “But the forecast after August 19 is of moderate to light rains. It will only increase the count, it will not be beneficial to the city. Short and intense showers only result in flooding, the rain water doesn’t get absorbed into the ground as it should,” added Palawat.