Strange summer trend: 'Game of Moisture' behind massive thunderstorms in North India

With frequent thunderstorm and dust storm hitting several parts of the country, this summer weather spells strange, weather experts say, adding that it is the "game of moisture".

Mritunjay Mohapatra, additional director general of India Meteorological Department, said May alone has witnessed three western disturbances until now while April saw one. The frequent western disturbances are one of the main reasons for the thunderstorms and dust storms, he said.

The three western disturbances in May caused weather fury that has so far claimed over 150 lives across northern India. 

Thunderstorms, dust storms, rainfall during summers are a normal summer phenomenon in northern India, but the severity of it has surprised the weatherman.

"The frequency of western disturbance is unusually high," said Mahesh Pahlawat, vice-president, Meteorology and Climate Change at Skymet.

The weather fury on May on 2-3 and May 13-14 saw wind gusting at over 100 kmph. Over 150 people were reported killed in Uttar Pradesh and Rajasthan due to the thunderstorm that wreaked havoc in the states.
         
It is only May, but unusually high temperatures have hit Western Rajasthan and adjoining parts of Pakistan. Cyclonic storm resulting from the western disturbances add to the intensity.

From October to March, Western disturbance is often observed over western Himalayas and north Indian plains. Its occurrence in April-May is unusual.

 "Usually, as the sun enters the northern hemisphere, the western disturbance shifts to upper latitude, north of India. However this year, the western disturbance continued over northern India and the western Himalayas," Palawat was quoted as saying by PTI.

The western disturbances this month were aided by easterlies - moisture-laden winds coming from the Bay of Bengal.       

"It still remains a question on why western disturbance have been occurring so frequently over western Himalayas and north India. It could be because of changing weather pattern that takes places every six-seven years," added.

A western disturbance originates in the Mediterranean Sea and brings rainfall to northwestern India. "This is all the game of moisture," L S Rathore, former IMD director general, said.