Why in news?

Several regions of north and west India experienced an unusually early rise in temperatures as the cool conditions of February quickly gave way to abnormally warm weather.

Temperatures were 8–13°C above normal, reaching levels that qualify as heat-wave conditions. Although a similar pattern occurred three years ago, such early onset of intense heat is uncommon.

What’s in Today’s Article?

• Western Disturbances: Key Winter Weather System
• Unusually Warm March Across India
• Dry Winter Behind Early Heat
• Rising Temperatures Threaten Rabi Crops

Western Disturbances: Key Winter Weather System

• A Western Disturbance is an eastward-moving weather system that originates over the Mediterranean Sea and surrounding regions.
• It is carried by westerly winds and travels long distances before reaching the Indian subcontinent.
• As the system moves towards northwest India through Pakistan, it gathers moisture.
• When this moist air collides with the Himalayan mountains, it rises and cools, resulting in cloud formation, rainfall, and snowfall.
• Importance for India’s Winter Climate
  • Western Disturbances are most active between December and February.
  • It serves as the primary source of winter rain and snowfall for northern states such as Jammu and Kashmir, Himachal Pradesh, Uttarakhand, Punjab, and Haryana.
  • Recent shifts in the pattern of Western Disturbances have led to reduced snowfall and rainfall in Himalayan regions, contributing to unusual weather patterns in India.

Unusually Warm March Across India

• The India Meteorological Department (IMD) had predicted above-normal day temperatures in western Himalayan regions, central India, and peninsular India for March, along with more heatwave days in Gujarat and Andhra Pradesh.
• These forecasts materialised within the first week of March, with several regions experiencing unusually high temperatures.
• For instance, Himachal Pradesh recorded temperatures above 25°C, which is rare for March since summer in Shimla usually peaks in May–June and heatwaves are uncommon.
• Similar conditions were observed in Jammu & Kashmir and Ladakh.
• According to the IMD, temperatures are expected to remain high for a few days but may decline with the arrival of a Western Disturbance, a winter weather system originating near Iran that brings moisture from the Mediterranean region.

Dry Winter Behind Early Heat

• The unusually warm conditions are partly due to a dry winter season.
• February was the third driest since 1901, with all-India rainfall in January–February only 16 mm, about 60% below normal. Both rainfall and snowfall remained significantly low.
• This occurred because of fewer Western Disturbances since November 2025, which normally bring winter precipitation.
• Additionally, the absence of wind convergence between westerly and easterly winds, which usually carries moisture to central and northern India, reduced rainfall further.
• Dry winters often lead to an early onset of summer heat, as the lack of soil moisture allows land to heat up more quickly, resulting in higher temperatures.

Rising Temperatures Threaten Rabi Crops

• The sudden increase in temperatures is likely to affect standing rabi crops such as mustard, wheat, gram, groundnut, sesame, sorghum, and safflower, along with vegetables like potato and fruits such as apples.
• Farmers have been advised to increase irrigation to maintain soil moisture, but this could place additional pressure on already stressed local water resources.