IMD Warns of Severe Heatwave in North India, Eyes Warning Norm Revision

India is likely to experience a spell of severe heatwave conditions in parts of Rajasthan and Uttar Pradesh over the coming week, according to the warning issued by the India Meteorological Department (IMD). The forecast further stated that southern and northeastern states would continue to see scattered thunderstorms and heavy rainfall.

The IMD forecast stated that heatwave conditions are likely to prevail over west Rajasthan from May 16 to 21 with severe heatwave conditions expected in some parts between May 18 and 21. Uttar Pradesh is also likely to witness heatwave conditions throughout the same period, with severe heatwave conditions forecast in some areas on May 18 and 19.

The met department also warned of heatwave conditions over Punjab, Haryana, Delhi and Maharashtra over the period between May 18 and 22.

Maximum temperatures are expected to rise gradually by 2-4 degrees Celsius in northwest India till May 18, while the western Himalayan region could see a sharper increase of 4-6 degrees Celsius by May 21.

Hot and humid conditions are very likely to prevail in parts of Konkan and Goa, while warm night conditions are likely in parts of Madhya Pradesh and Vidarbha on May 16.

IMD to Change Warning Parameters

The IMD, along with its technical partners, will soon revise the criteria for declaring heatwave conditions in the country, as the present parameters do not suit India’s geographical conditions, reported PTI.

Kerala, in particular, has faced difficulties in issuing heatwave warnings because of the limitations of the existing parameters.

Sources in the India Meteorological Department told PTI that the state experienced severe heat and humidity this summer and, for the first time, weather forecasts were made based on the anti-cyclone system that formed near the Karnataka–Maharashtra coast.

"We have never had an anti-cyclone system form closer to the South before, and this time we had to predict the weather based on it," a senior IMD official told PTI.

Anti-cyclonic systems are common over north-western parts of India, but this year one formed near the southern region, leading to unusually hot nights.

The anti-cyclone caused downward air movement, which pushed warm air towards the surface and prevented it from dispersing at night, the official added. As a result, Kerala recorded night temperatures 3 to 4 degrees Celsius above normal.

Because Kerala has experienced a steady temperature increase during the summer months for the last few years, changing the parameters for declaring heat waves would benefit the state, enabling the authorities to issue warnings more efficiently, the official added.

The IMD currently issues hot and humid weather warnings, although the situation warrants a heatwave warning, as the existing parameters do not allow the department to issue one.

(With inputs from PTI.)