Fatal thunderstorms outcome of atmospheric cocktail, say experts

At least 59 people in two states died due to incidents connected with a thunderstorm that ripped through swathes of northern India late on Wednesday, officials said on Thursday.

- Jayashree Nandi and Jasjeev Gandhiok

NEW DELHI:

Meteorologists studying the storm said the system was the product of a complex atmospheric cocktail—multiple cyclonic circulations, abundant moisture from two seas on either side of the subcontinent, and extreme daytime heating—all supercharged by unusual persistence of the winter weather system known as Western Disturbances that should have retreated by now.

The phenomenon appears linked to unusual weather continents away—record heat in the Arctic Circle that is displacing cold air southward, triggering unseasonable cold across locations such as the US Eastern Seaboard. This disruption echoes similar unusual shifts in a key weather system impacting India at present.

M Rajeevan, the former secretary of the ministry of earth sciences said western disturbances—Mediterranean-origin cyclones that normally impact India in winter before moving to northern latitudes during summer—have persisted well into summer.

"You expect western disturbances to move north of the Indian region in April, May, June months. In some years we are seeing that their impact is continuing in summer which is not good for the monsoon," Rajeevan said.

Rajeevan's assessment of what is happening in India is similar to developments thousands of kilometres away. Parts of Iceland logged near-record temperatures of 27°C in the Arctic Circle, while western Greenland hit 19.9°C, well above average for the time of year.