A heatwave is declared when the maximum temperature goes up to 40 degrees Celsius or more and is at least 4.5 degrees above normal. A severe heatwave is declared if the maximum temperature crosses over the 47-degree Celsius mark

The weather department has issued an orange alert, warning about severe heatwave conditions in the national capital

Heat wave conditions in some parts are very likely over Vidarbha on Monday and in isolated pockets over Vidarbha and north Madhya Pradesh are likely on Monday and Tuesday

The weather department said a thunderstorm or a dust storm is likely in Delhi on Monday

Delhi, Haryana and Uttar Pradesh, have been experiencing record high temperatures over the past two months. In the last week of April, the city saw temperatures rise up to 46 degrees Celsius due to a heatwave

The average maximum temperature in April for North West and Central India was the highest in 122 years

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)