India, June 10 -- A pre-monsoon storm that struck Delhi on Tuesday evening and continued through the night reached 128 km/hour at Pusa - higher than the 120 km/hr recorded at Palam airport hours earlier, which had already diverted at least two flights and delayed more than 400 others. Across the city, residents woke on Wednesday to fallen trees and blocked roads, with localities including Hauz Khas, Defence Colony, Panchsheel Park and Vasant Kunj among the worst affected; photos posted to X showed uprooted trees that had crushed boundary walls and brought pavements up with their roots.

Most of that destruction arrived with almost no rain.

The mechanism behind the storm, and behind the unusual frequency of such events this pre-monsoon se...