New Delhi, Sep 16 (PTI) The country will witness an extended monsoon spell this year as rainfall activity over north India shows no signs that it will decline till the end of September, the India Meteorological Department (IMD) said on Thursday.  It added that overall above normal rainfall activity is likely over northwest, central India, near-normal over south peninsular India and below-normal over east and northeast India.

According to the IMD, the Southwest Monsoon withdrawal from northwest India takes place if there is cessation of rainfall activity over the area for continuous five days.

An anticyclonic wind has to form over the lower troposphere, and there should also be considerable reduction in moisture content.

"There are no signs of monsoon withdrawal from north India for the next 10 days," IMD Director General Mrutunjay Mohapatra said.

In a statement, the IMD said conditions are not likely to be favourable for the commencement of the withdrawal of monsoon from parts of northwest India before the end of the week from September 23-29.  "This is due to the expected normal to active monsoon conditions and as a consecutive formation of two cyclonic circulations over the Bay of Bengal and their west-northwestwards movement across central and adjoining northwest India," the IMD said.  Last year, the IMD had revised the date for the withdrawal of monsoon from northwest India by nearly a fortnight. This was done keeping in mind the trend of a delayed retreat of monsoon observed over the last few years.

The Southwest Monsoon starts withdrawing from west Rajasthan first. According to the revised date, it starts withdrawing from Pokhran from September 17.

The Southwest Monsoon saw delayed withdrawals in 2017, 2018, 2019 and 2020.

A delayed withdrawal of monsoon also means a delayed onset of winter.

Officially, the Southwest Monsoon season starts on June 1 and lasts till September 30.