ANSWER: Temperatures are greater than 4.5° C above what’s usual for the region
Explanation:
Heat Wave - Temperatures are greater than 4.5° C above what’s usual for the region.
Cold Wave - Temperatures are less than 4.5° C below what’s usual for the region
Severe Heat wave – Maximum temperature greater than or equal to 47° C
Severe Cold Wave – Minimum temperature is 2° C or less.
If India’s monsoon rainfall were to dip below 10 per cent of the normal and span between 20 and 40 per cent of the country’s area, it would be called a “deficient” year instead of an “All India Drought Year” as the IMD’s older manuals would say. A more severe instance, where the deficit exceeds 40 per cent and would have been called an “All India Severe Drought Year,” will now be a “Large Deficient Year”.
