IMD disagrees with Skymet, says India will have a normal monsoon this year

India is expected to see a normal monsoon this year with a long-period average (LPA) of 96 per cent between June and September, says IMD

India is expected to see a normal monsoon this year with a long-period average (LPA) of 96 per cent between June and September, according to the Indian Meteorological Department (IMD). In a media briefing, M Ravichandran, secretary, Ministry of Earth Sciences, said that IMD expects monsoon 2023 to be normal with a rainfall of 83.5 centimetres.  

"India to see normal rainfall during the southwest monsoon season (from June to September). It is likely to be 96 per cent (with an error margin of 5 per cent) of the long-period average of roughly 87 cm," Ravichandran said. 

There is a 67 per cent probability of normal to above normal rainfall, said M Mohapatra, director general of Meteorology, IMD.

Mohapatra said the snow-covered area over the northern hemisphere and Eurasia was below normal from December 2022 to March 2023.

A lower snow cover over the northern hemisphere is considered favourable for the subsequent southwest monsoon rainfall over India.

"If at all there is any adverse impact due to the evolving El Nino conditions during the monsoon season, it is likely to be countered by the favourable impact of a positive IOD and the lower snow cover over the northern hemisphere," Mohapatra said.

Starting 2019, India has witnessed four consecutive years of normal and above-normal rains during the monsoon season.

This comes just a day after India's private forecaster Skymet predicted a "below normal" rainfall this monsoon with an LPA of 94 per cent.

IMD said that region-wise normal rains are expected over peninsular India, adjoining East Central India, East India, North East India and North West India. It also noted that below-normal conditions might prevail over some parts of North West India, parts of West Central India and North East India.

El Nino impact during second half of the monsoon season

IMD added that El Nino's impact might be felt during the second half of the monsoon season. Also, in the past, 60 per cent of El Nino years have been normal monsoon years.

Why is rainfall important to India?

According to the Ministry of Agriculture, 51 per cent of India's farmed area, accounting for 40 per cent of production, is rain-fed and monsoon critical. Moreover, 47 per cent of India's population depends on agriculture for their livelihood. So, a good monsoon is directly correlated to a healthy rural economy.

What is a "normal" monsoon?

IMD uses the long-period average (LPA) to determine if the rainfall is "normal", "below normal", or "above normal". The LPA, according to IMD's website, "is the rainfall recorded over a particular region for a given interval (like month or season) average over a long period like 30 years, 50 years, etc."

Usually, in India, a 50-year LPA covers large variations on either side caused by years of unusually high or low rainfall due to El Nino or La Nina.

India defines average, or normal, rainfall as between 96 per cent and 104 per cent of a 50-year average of 88 centimetres (35 inches) for the four-month season beginning June.

IMD maintains LPAs for the entire country on a national and local level.

What is a "below normal" monsoon?

If the seasonal rainfall is between 90 to 95 per cent of LPA, it is called a "below normal" monsoon.

What are "above normal" and "excess" monsoons?

If the seasonal rainfall is between 105 to 110 per cent of LPA, it is called above normal monsoon. Moreover, if it is above 110 per cent of LPA, it is called "excess" rainfall.