LOO & ANDHI

PRERNA FOR IAS

LOO & ANDHI

1. Loo (Hot Summer Wind) – Introduction

Loo is a strong, hot, dry, and dusty wind that blows during the summer season in northern and northwestern parts of India and Pakistan. It is one of the most severe weather phenomena of the Indian summer. The wind generally blows from west to east during the months of May and June. Loo develops due to intense heating of the land surface under clear skies. It significantly increases daytime temperatures and creates extremely uncomfortable conditions. Exposure to Loo for prolonged periods can cause dehydration, heat exhaustion, and heatstroke. Therefore, it is considered a dangerous climatic phenomenon.

2. When and Where Does Loo Blow?

Loo mainly blows during May and June, just before the arrival of the southwest monsoon. It is most common in the afternoon when temperatures reach their peak. The wind affects northwestern and northern India, including Rajasthan, Punjab, Haryana, Delhi, western Uttar Pradesh, and adjoining regions. It also extends into parts of Pakistan. Loo generally blows from the arid regions of western India toward the eastern plains. Since it occurs during the hottest period of the year, it intensifies summer conditions and makes outdoor activities difficult. Its influence decreases rapidly with the arrival of monsoon rains.

3. Temperature and Characteristics of Loo

Loo is characterized by extremely high temperatures, low humidity, and dry conditions. The temperature of Loo usually ranges between 45°C and 50°C and may sometimes exceed 47°C. The air is very dry and often carries dust particles, creating dusty conditions. Humidity remains extremely low, which increases evaporation from the body and leads to dehydration. Loo usually blows during the daytime and weakens after sunset. Its hot and dry nature makes it hazardous for human health, agriculture, and livestock. The phenomenon is considered a major climatic feature of the Indian summer season.

4. Formation of Loo

Loo develops because of intense solar heating during summer. In northwestern India, especially over Rajasthan and adjoining desert regions, the land surface becomes extremely hot. This creates a low-pressure area that heats the surrounding air. The heated air becomes dry and moves across the northern plains as strong winds. Since there is little moisture in the atmosphere before the monsoon, the winds remain hot and dry. Clear skies and prolonged sunshine further intensify the process. Thus, Loo is essentially a result of extreme land heating combined with dry atmospheric conditions during the pre-monsoon season.

5. Effects of Loo