Western disturbances, a weather system bringing winter snow and rain to northern India, have been increasing during summer months, according to a recent study. Traditionally active from December to March, these disturbances now occur more frequently in May, June, and July, doubling their incidence in June over the past 20 years. Originating from the west, they carry moisture from the Arabian Sea and cause precipitation in Himalayan states like Himachal Pradesh, Uttarakhand, and Jammu & Kashmir. Winter snowfall from these disturbances feeds rivers such as the Indus and Ganga, supporting irrigation and domestic water needs for about 500 million people. However, the extension of western disturbances into summer, combined with the monsoon, has led to increased flooding risks. Climate changes, including warming polar regions and weakening subtropical jet streams, are contributing to this shift by prolonging the presence of western disturbances over India. Scientists note that while winter winds are dry and less flood-prone, summer occurrences with monsoon moisture pose greater hazards. This evolving pattern has implications for water management and disaster preparedness in northern India. (Updated 18 Aug 2025, 15:38 IST; source: link)