Several parts of north India are reeling under an intense heatwave with many districts in Rajasthan, Haryana, Uttar Pradesh, Madhya Pradesh posting temperatures over 45 degrees Celsius or five degrees above what is normal.
A Heat Wave is a period of abnormally high temperatures, more than the normal maximum temperature that occurs during the summer season.
The Indian Meteorological Department (IMD) has given the following criteria for Heat Waves
Heat Wave need not be considered till the maximum temperature of a station reaches at least 40°C for Plains and at least 30°C for Hilly regions.
When the actual maximum temperature remains 45°C or more irrespective of normal maximum temperature, heat waves should be declared.