Several parts of India grappled with unusually high temperatures this week, forcing schools to close and hospitals to create special units to treat heat-related illnesses, while workers on construction sites were given a "paid holiday" in the afternoon. Here is a look at what caused the unprecedented heat in the country. HOW UNUSUAL HAS THE SITUATION BEEN THIS YEAR? While every year temperatures in India tend to peak in the months of May and June, the number of heatwave days recorded over northwestern and eastern parts of the country this season have been more than double the normal, with eastern India also experiencing its hottest April on record. India declares a heatwave day when the maximum temperature in any given region is 4.5 -6.4 degrees Celsius higher than normal. Parts of the country have touched new highs in terms of the maximum temperature, including Delhi, which recorded the country's highest ever temperature at 52.9 C (127.22 degree F) on Wednesday. Wh...