The Southwest monsoon, which brings more than 75 per cent of the country’s rainfall during June-September, will be normal this year, Skymet Weather, a private weather forecaster said on Tuesday.
G P Sharma, President (Meteorology) of the Skymet Weather said the Long Period Average (LPA) of the rainfall during June to September will be 103 per cent with an error margin of plus or minus 5 per cent.
“That is the healthy normal,” Sharma said.
He added that there is 60 per cent probability of a ‘normal’ monsoon and 15 per cent probability of ‘above normal’ rainfall.
Monsoon in the range of 96-104 of the LPA is considered to be normal and 103 per cent of the LPA is on the higher side of the normal range.
On a monthly scale, June is likely to receive rainfall of 106 per cent of LPA, while July is expected to record 97 per cent of LPA. August and September are expected to receive 99 per cent and 116 per cent of the LPA, the Skymet said.
Sharma said 2021 will be the third consecutive year of a good monsoon. Last two years have recorded above normal rainfall.
In terms of geographical risk, the plains of north India along with a few parts of the northeast region are likely to be at risk of being rain deficient through the season, the Skymet said.
“Also, interior parts of Karnataka face the scare of scanty rains in the core monsoon months of July and August. The onset month of June and the withdrawal phase of September is assuring good countrywide rainfall distribution,” it added.
Yogesh Patil, CEO, Skymet, said the La Nina conditions prevailing in the Pacific Ocean since last year presage softening and are expected to remain neutral through the monsoon season.
La Nina refers to the cooling of the Pacific waters. It has an impact over the sub-continent’s weather.
“ENSO continues to wield a spike mid-way through the season suggesting a fresh phase of cooling, albeit marginal, over the central Pacific Ocean. Therefore, the occurrence of El Nino, which normally corrupts the monsoon, is ruled out,” he said.
Indian Ocean Dipole (IOD) is neutral and is oscillating lightly on either side of the zero line. This parameter seems to incline with a negative shift but remaining within the threshold limits. In this case, it may not heave the monsoon spurts but will refrain from harming the season, the Skymet added.
Negative IOD refers to the warming of Indian Ocean waters and positive IOD refers to its cooling.
The India Meteorological Department (IMD), the country’s official weather forecaster, is likely to release its monsoon forecast later this week.