Parts of Mumbai witnessed heavy rainfall on early Saturday as the Southwest Monsoon, which is already delayed by more than a week, is expected to reach the city today, according to India Meteorological Department (IMD). The IMD has issued a yellow alert for the city on June 26-27, indicating heavy rainfall in isolated areas.

On Thursday, the weather department said that monsoon is likely to reach Mumbai by June 24, but a formal announcement is yet to be done.

"Conditions are favourable for the monsoon to move further towards Raigad, Thane, Mumbai and Palghar. Monsoon is likely to reach Mumbai by June 24," said IMD Mumbai earlier, as per an ANI report.

Typically, the monsoon officially begins in Mumbai in the second week of June. However, the IMD had last week stated that the Southwest monsoon is in the process of resuming its trajectory post-Cyclone Biparjoy, which has been the longest storm in Arabian Sea.

Separately, an IMD official said that the Southwest monsoon is likely to arrive in Madhya Pradesh over the weekend, even as 18 districts recorded more than 1.5 inch pre-monsoon showers in just 12 hours ending 8.30 pm on Friday.