Unusual occurrences of leaves of plants being scorched during the monsoons

Explanation - A *heat burst.*The monsoons showers started in Kerala some days ago. The temperatures have come down and the winds are cool.

In between unusual occurrences of hot winds blowing for short periods were observed - discussed by many who experienced it. These winds scorched leaves of plants, including the leaves of tall, standing, healthy coconut palms. Leaves of the hardy oleander plant were scorched too. The affected leaves were quickly pruned and checked out for the usual invasive beetles, insects...there were none.

This occurrence was recently reported in some sections of the media. One of the media reports is given below-

THRISSUR: A team of scientists from Peechi Kerala Forest Research Institute (KFRI), which visited some coastal areas that witnessed wilting of plants last week, has reported that it could be the result of a phenomenon called heat burst. The scientists said heat burst was a rare atmospheric phenomenon characterized by gusty winds and a rapid increase in temperature and dip in dew point (moisture).

The team, comprising S Sandeep of KFRI's department of soil science, sustainable forest management division, ecologist K A Sreejith and economist V Anita, had visited areas like Purakkad in Alappuzha and coastal areas of Kollam and Thrissur. They have submitted their preliminary findings to the state council for science, technology and environment (KSCSTE), which ordered the study. "We have also collected samples of soil and water besides the weather data of these areas for detailed studies," Sandeep said. "Heat bursts typically occur during night and are associated with decaying thunderstorms. They are characterized by extremely dry air and very strong, even damaging, winds."

He said earlier reports suggested that temperatures could rise by 11°C or more within a few minutes during heat bursts and this could lead to a rapid evaporation of water from leaves and subsequent wilting. He, however, said no damage to human beings had been reported. KSCSTE executive vice-chairman Suresh Das said similar phenomenon had been reported in other parts of the world. No trace of acid or other chemicals was detected anywhere, he said. The council has also asked the centre for water resources development and management to conduct studies in the northern areas.
Links: 'Heat burst led to wilting of leaves' -The Times of India
'No convincing answers yet on scorching wind phenomenon' The Hindu