Monsoon covers nearly half the country in a week, six days ahead of schedule
Monsoon has advanced into parts of Gujarat, Madhya Pradesh, Chhattisgarh, Odisha, and remaining areas of Maharashtra, Telangana, Andhra Pradesh six days ahead of schedule, the India Meteorological Department (IMD) said on Thursday. Monsoon is expected to reach Delhi earlier than expected, IMD added.
“In the next 48 hours, monsoon will reach parts of east Uttar Pradesh and Bihar. In the subsequent two days, the monsoon may cover west Uttar Pradesh and parts of Uttarakhand also. So, the expectation is that it will reach Delhi earlier than expected,” said Kuldeep Shrivastava, who heads the Regional Weather Forecasting Centre.
Monsoon normally arrives in Delhi by June-end.
Srivastava said certain conditions will have to be met before they declare the onset of monsoon in Delhi. “It should have rained in a large area for a couple of days, the easterly wind pattern should be established, and it should have covered Bihar, parts of Uttar Pradesh, etc,” he said.
RK Jenamani, senior scientist, National Weather Forecasting Centre, echoed Srivastava and said that before the early arrival of the monsoon in northwest India, there will be widespread and heavy rains in east and central India. “There is a warning of lightning for central India, Bihar, Odisha, etc. People should be careful.”
The arrival of monsoon, which is crucial to the country’s farm-dependent economy, is announced based on factors such as wind speed, consistency of rainfall, intensity, and cloud cover. The monsoon arrived in Kerala on June 3 two days behind schedule. It arrives there first before covering the rest of India by July.
The early expected arrival of the monsoon in northwest India including Delhi is expected to bring relief from the muggy weather.
IMD said the country has recorded 21% excess rainfall between June 1 and 9. Out of 36 subdivisions, 11 have recorded large excess rains (60% above normal), seven excess (20 to 59%), 10 normal (-19 to 19%).
In its second long-range forecast, IMD said monsoon rainfall was likely to be normal at 101% of the long-period average (LPA) after two years of above-average rainfall. LPA is the average rainfall (88cm) recorded in India every year between June and September from 1961 to 2010.
Good rainfall has been a prime reason for the farm sector’s resilience for two years, and its ability last year to buck the Covid-19 pandemic.
In 2020 and 2019, the monsoon was above normal at 110% and 109% of LPA. In 1996, 1997, and 1998, the monsoon was normal at 103.4%, 102.2%, and 104%, according to IMD. India recorded 18% excess rain during the pre-monsoon period from March 1 to May 31.
IMD said the monsoon also advanced to the remaining parts of the Central Bay of Bengal and most parts of the North Bay of Bengal on Thursday. The northern limit of the monsoon passes through Surat, Nandurbar, Betul, Mandla, Bilaspur, Bolangir, Puri, and Bagdogra.
IMD said conditions were favourable for further advance of southwest monsoon into more parts of Gujarat, Madhya Pradesh, remaining parts Chhattisgarh and Odisha, entire West Bengal and Jharkhand, and parts of Bihar and east Uttar Pradesh and remaining parts of north Bay of Bengal during the next 48 hours.
Ministry of earth sciences secretary M Rajeevan said the monsoon is very active now and their models indicate that it will be active for another week. “Some of our models are indicating a slight weakening of the monsoon towards the end of the month. Monsoon is normally active during onset, plus a low-pressure area developing over the Bay of Bengal is also helping it progress.”
IMD said a cyclonic circulation was lying over the northwest Bay of Bengal. Under its influence, a low-pressure area is likely to form over the northwest Bay of Bengal and neighbourhood during the next 24 hours. It is likely to become more marked during subsequent 24 hours and move west-north-westwards across Odisha. Under its influence, fairly widespread to widespread rainfall activity with isolated to scattered heavy to very heavy rainfall was very likely in most parts of east India and adjoining central India from Thursday.
Extremely heavy rain (≥ 20 cm) was also likely in Odisha on June 11 and 12, Chhattisgarh during June 11 and 13, east Madhya Pradesh on June 13, Vidarbha on June 12 and 13.
Due to the strengthening of westerly winds along the west coast in association with the low-pressure area, widespread rainfall activity with heavy to very heavy rain was likely to continue in coastal districts of Maharashtra from June 10 to 11 and in coastal Karnataka from June 12 to 15. Extremely heavy rain is also likely in the Konkan region.
Due to the west-north-westwards movement of the low-pressure area, fairly widespread to widespread rainfall activity is likely in northwest India from June 12 to 14.
Ahead of monsoon onset, fairly widespread thunderstorm activity accompanied by frequent cloud to ground lightning was likely in Madhya Pradesh, Uttar Pradesh, Vidarbha, Chhattisgarh, Odisha, Bengal, Jharkhand, and Bihar during the next two days, IMD has warned. Deaths due to lightning are reported in the monsoon season particularly in Bihar and Uttar Pradesh.
“In monsoon season hydrometeoric (water or ice particles) concentration is more so there is more charge build-up. If it is a very high cloud, then charge neutralisation happens within the cloud also called intra-cloud lightning. If cloud height is high but not extremely high, there is more charge separation and cloud to ground lightning. Cloud life during monsoon is longer and it moves slowly so there are a number of flashes in a small region. Kharif crops are planted in this season. Paddy field acts as an ionic fluid and many farmers get electrocuted at once,” Soma Sen Roy, a member of the ministry of earth sciences’ thunderstorm working group, said last year.
India receives about 70% of its annual rain during the four-month monsoon that is crucial for rice, soybean, and cotton cultivation. As much as 60% of the sown area does not have access to irrigation in India, where over 150 million farmers and nearly half of the population are dependent on a farm-based income. The monsoon also replenishes 89 nationally important reservoirs critical for drinking and power generation.