The southwest monsoon is expected to reach the Kerala coast around June 1, the India Meteorological Department (IMD) said on Thursday.

The IMD changed its initial forecast, which had predicted monsoon was likely to be delayed by a week due to Cyclone Amphan.

"With the strengthening of westerlies and increase in convective clouds, the Southwest Monsoon has further advanced into some parts of the Maldives-Comorin area, some more parts of south Bay of Bengal, remaining parts of Andaman Sea and Andaman & Nicobar Islands," the IMD said in a bulletin.

The monsoon is expected to advance in some more parts of the Maldives-Comorin area during the next 48 hours. "Conditions are very likely to become favourable from June 1 for the onset of Southwest Monsoon over Kerala," it added.

The maximum temperatures are likely to recede from Thursday in north India, which is reeling under a severe heatwave, the India Meteorological Department said. The temperatures north and central India have soared over 47 degrees Celsius at a few places for the past four-five days.

The IMD changed its initial forecast, where it had predicted the monsoon was likely to be delayed by a week due to Cyclone Amphan.

The maximum temperature in Churu, which had recorded 50 degrees Celsius on Tuesday, was 49.6 degrees, followed by 48.9 degrees in Ganganagar and Bikaner districts of Rajasthan. Bathinda in Punjab recorded 47.5 degrees Celsius, while it was 47.2 degrees in Delhi.

"Under the influence of a western disturbance and an east-west trough and likely occurrence of rain/thunderstorm from May 28-30, maximum temperatures over plains of north India likely to recede from May 28 onwards with a substantial reduction of heatwave conditions from May 29," the IMD said.

Western disturbance is a cyclonic circulation that originates in the Mediterranean Sea. Traversing central Asia, it brings rains to the hills and plains when it comes in contact with the Himalayas.

Delhi on Tuesday recorded the highest temperatures in May in 18 years at 46 degrees Celsius. The highest ever temperature for the month of May was recorded on May 29,1944, when the city’s temperature soured to 47.2 degrees Celsius, according to the Safdarjung Observatory.