New Delhi: A rare and expansive weather system stretching nearly 1,000 kilometres is sweeping across parts of Afghanistan, Pakistan, and India, bringing an unexpected burst of rain, thunderstorms, and gusty winds at a time when the region typically begins transitioning into summer heat.
Meteorologists say the current system stands out due to both its timing and structure. Unlike the usual curved path associated with a Western Disturbance, this event has formed as a long, nearly straight band of low pressure cutting across the region. Such a linear formation is considered uncommon and highlights increasingly erratic weather patterns.
The system is being driven by an upper-air cyclonic circulation centred over northern Pakistan. This has resulted in widespread atmospheric instability, triggering thunderstorms, wind speeds ranging between 40 and 80 kmph, scattered hailstorms, and precipitation across large swathes of the subcontinent.
Several regions have already experienced significant weather activity. Heavy rainfall has been reported in eastern Himalayan areas such as Sikkim and sub-Himalayan West Bengal, while southern states including Karnataka, Andhra Pradesh, Kerala, and Tamil Nadu have also received notable showers. Isolated hailstorms have been recorded in multiple areas.
Experts explain that the disturbance features a trough in the upper atmosphere, which is interacting with several smaller cyclonic systems at lower levels. These are spread across regions such as Madhya Pradesh, Uttar Pradesh, Rajasthan, Haryana, Assam, and coastal belts of southern India. This interaction has intensified cloud formation and rainfall activity.
The moisture fueling this large-scale system has travelled a long distance. It originates from evaporation over water bodies such as the Mediterranean Sea, Caspian Sea, Black Sea, and the Persian Gulf. As the system moves eastward, it gathers additional moisture from the Arabian Sea, which intensifies precipitation when lifted over the Himalayan terrain.
In the national capital region, Delhi and nearby areas are expected to receive light to moderate rainfall accompanied by thunderstorms and gusty winds through Friday. Daytime temperatures are likely to remain below normal, hovering in the mid-to-high 20s Celsius.
Weather scientists note that such widespread activity in late March is uncommon. Typically, western disturbances are most active during winter months and weaken significantly as spring progresses. The persistence and scale of the current system, along with its atypical structure, underline shifting climatic patterns in the region.
While the present disturbance is expected to gradually weaken after today in northern areas, forecasts indicate that another, albeit weaker, system could arrive around March 22, potentially extending unsettled weather conditions further.
