Thiruvananthapuram: Kerala is still deficient in monsoon rainfall despite heavy rains lashing several parts of the state in the last few days, the India Meteorological Department (IMD) said.

Kerala received 34 per cent deficient rainfall during the south-west monsoon this year while the country as a whole got six per cent deficit rains.

As the south-west monsoon is now in the withdrawal phase, the rains are expected to reduce from Wednesday, October 4, onwards, IMD sources said.

The heavy rains which lashed many parts of Kerala on Tuesday were due to the low pressure system over Jharkhand, they said and added that the withdrawal of the monsoon was complete in three to four states of north-west India.

"The conditions are favourable for the withdrawal of the south-west monsoons. The rains will reduce from tomorrow," K Santhosh, director of the Regional Meteorological Centre, Trivandrum told PTI.

He said Lakshadweep received a 15 per cent deficit rainfall but that is considered normal.

"Upto 19 per cent variability is considered a normal monsoon in certain areas. However, south peninsular India received a deficit rainfall as the total rainfall was only 92 per cent," Santhosh said.

India received 92 per cent rain during the monsoon season, a 6 per cent low in the long-period average. The country has recorded a total of 814.9 mm of rain against the normal average of 865 mm.

Gujarat reported rainfall deficiency of 90.67 per cent, followed by Kerala at 86.61 per cent, Rajasthan at 80.15 per cent, Karnataka at 74.16 per cent, and Telangana at 64.66 per cent.

He said the present rainfall in Kerala is because of the low pressure system over Jharkhand.

"This is expected to move westwards and the westerly winds have also slackened. So rainfall is likely to reduce from tomorrow," Santhosh said.

Admitting that there has been a change in the monsoon pattern in India in recent years, the director said that one of the contributing factors could be climate change.

"Some days we have excess rainfall and the dry spell days have increased. There is a higher variability in monsoon showers," Santhosh said.

He said the El Nino in the Pacific has affected the monsoon pattern in India.

"The Indian Ocean dipole is positive. So when we have an El Nino coupled with the Indian Ocean dipole positive, we are expecting to have heavier rains during the north-west monsoon," Santhosh said.

The monsoon season this year had a late onset and sluggish progress due to the El Nino effect.

Many parts of the country suffered from extreme weather events during the four-month-long monsoon season.

The cyclone Biporjoy over the Arabian Sea, which is a clear indication of the Arabian Sea heating up due to climate change, during the month of June, helped the onset of monsoon over Kerala, but it sucked out all the moisture from the air and stalled the progress and performance of the monsoon in June.

The absence of monsoon rains also paved the way for humid heat waves across East India, a phenomenon which is becoming worse due to global warming with excessive evaporation and moisture in the atmosphere.

The September rains have helped the country improve its water tables and save it from a possible drought. 

(With PTI inputs)