The India Meteorological Department (IMD) on Monday said that cumulative all-India average monsoon rainfall in September is expected to be ‘below normal’, continuing a broad trend that started in June and has led to 47 per cent of the country recording deficient or very deficient rainfall to date.

IMD said a strengthening El Niño will mean below-normal rain in September, except for some areas of Northwest, Northeast, East, East-Central and Southeast Peninsular India.

The month is also likely to be warmer than usual for most parts of the country.

It said September rains are expected to be lower than 91 per cent of the long-period average (LPA). The LPA for September is about 167.9 millimetres.

A below-par monsoon in September, coupled with a rise in temperature, could impact the yield of standing crops, particularly in areas that were sown late or lack adequate irrigation facilities.

“El Niño is expected to withdraw or weaken only in February or March,” the met department said.

The IMD said that monsoon rains — from June to August — have been 13.8 per cent deficient, with August witnessing a 16.3 per cent rain deficiency even as the month had four low-pressure systems with 26 low-pressure days.

Around 350 districts, or 47 per cent of the country, have reported deficient or very deficient rainfall until 31 August, IMD said.

IMD also said that August was the warmest recorded since 1901 at 28.01 degrees Celsius due to deficient rainfall and moderate to strong El Niño conditions over the equatorial Pacific.

So far in the monsoon season, IMD said that Southern Peninsular India, including states like Tamil Nadu, Kerala, Karnataka, Andhra Pradesh and Telangana, has recorded a cumulative deficiency of 24.2 per cent, while East and Northeast India had a 25.7 per cent deficiency.

Punjab, eastern Uttar Pradesh, Bihar, southern West Bengal, Sikkim and Meghalaya were among the states that witnessed below-normal rains so far in the monsoon season.