The minimum temperature in Delhi on Saturday settled at 28.7 degrees Celsius, a notch above normal, the India Meteorological Department (IMD) said.

The maximum temperature is expected to touch 44 degrees Celsius, it said.

According to ndtv.com, heatwave will prevail in parts of northwest, central India over the next 2-3 days, informed the weather office.

The national capital is likely to witness clear skies in the day and heatwave conditions are expected at a few places, the weather office said.

The IMD has issued a yellow alert, warning of a heatwave at isolated places in the capital. The mercury may increase to 44 degrees Celsius at the Safdarjung observatory, it said.

The Safdarjung observatory, Delhi's base station, had recorded a maximum temperature of 42.9 degrees Celsius on Friday.

The IMD uses four colour codes for weather warnings -- green (no action needed), yellow (watch and stay updated), orange (be prepared) and red (take action).

"Heatwave is back over parts of Rajasthan, Madhya Pradesh, south Uttar Pradesh and isolated pockets of Delhi-NCR," said Mahesh Palawat, vice president (climate change and meteorology), Skymet Weather.

A heatwave is declared when the maximum temperature is over 40 degrees Celsius and at least 4.5 notches above normal.