Heat wave conditions are predicted in parts of east India over the next four days and the northwest region of the country over the next two days, the Met office said on Monday.

The Gangetic West Bengal and Bihar may see heat wave conditions for four days on the trot. Sikkim, Odisha and Jharkhand may also experience heat wave conditions over the next two to three days.

Similar conditions are expected in isolated pockets over Punjab and Haryana on April 17, and western Uttar Pradesh on April 18. Eastern Uttar Pradesh may also be affected on April 18-19, the India Meteorological Department (IMD) said.

Heat wave conditions have been prevailing in isolated pockets of the Gangetic West Bengal for the last six days, coastal Andhra Pradesh for four days and Bihar for three days, it said. The Met office said a western disturbance active in the western Himalayan region will provide some relief from the soaring temperatures in the plains of northwest India starting Tuesday.

Punjab, Haryana, Delhi and Rajasthan are likely to experience isolated to scattered rainfall during April 18-20, it said. Heavy rainfall is anticipated in isolated areas of Jammu and Kashmir, and Ladakh on April 18.

Himachal Pradesh and Uttarakhand are expected to experience heavy rainfall on April 18-19.?Isolated hailstorms are likely over Himachal Pradesh, Uttarakhand and Punjab over the next two-three days.

The threshold for a heat wave is met when the maximum temperature of a station reaches at least 40 degrees Celsius in the plains, at least 37 degrees Celsius in coastal areas, and at least 30 degrees Celsius in hilly regions, and the departure from normal is at least 4.5 degrees.

Earlier this month, the Met office predicted above-normal maximum temperatures for most parts of the country from April to June, except parts of the northwest and the peninsular regions. Above-normal heat wave days are expected in most parts of central, east and northwest India during this period.