After a subdued performance for much of July, the southwest monsoon is set to make a strong comeback, bringing renewed rainfall to large parts of the country. Following weeks of sparse showers, rising temperatures and prolonged dry conditions across the plains, the India Meteorological Department (IMD) has forecast a revival of monsoon activity beginning early next week.
Rain to Return Across Several Regions
According to the IMD, the monsoon is expected to regain strength over Northeast India before gradually expanding into eastern, central and northern parts of the country.
Many regions are likely to experience widespread rainfall accompanied by thunderstorms, while isolated areas could receive heavy showers. The expected revival is likely to bring much-needed relief to the Gangetic plains and Central India, where hot and humid conditions have persisted for most of the month.
What Is Driving the Revival?
The primary factor behind the monsoon's return is the formation of a fresh low-pressure area over the Bay of Bengal.
A low-pressure system develops when warm air rises, drawing moisture-laden winds from the surrounding seas into the atmosphere. This process promotes the formation of dense rain-bearing clouds. As the system moves inland from the Bay of Bengal toward central India, it is expected to strengthen monsoon activity across a wider region.
The movement of this weather system will also help restore the monsoon trough, an elongated zone of low pressure extending across northern India that plays a crucial role in determining the distribution of monsoon rainfall.
Over the past several weeks, the monsoon trough had shifted closer to the Himalayan foothills, resulting in heavy rainfall over the hills while leaving much of the northern and central plains comparatively dry. As the trough shifts southward again, moisture from both the Bay of Bengal and the Arabian Sea is expected to penetrate deeper inland, leading to more widespread rainfall.
Why Did the Monsoon Weaken in July?
Meteorologists attribute the recent dry spell to a "break monsoon" phase, a common phenomenon during which the monsoon trough shifts northwards, reducing rainfall across central India.
During this period, very few low-pressure systems developed over the Bay of Bengal, while moisture-laden winds from the Arabian Sea weakened considerably. At the same time, descending air currents over much of the country suppressed cloud formation, limiting rainfall.
As a result, India has recorded a rainfall deficit of nearly 24 per cent so far this season, receiving approximately 244.6 mm of rainfall compared to the normal average of 323.1 mm.
Why Has the Heat Been So Intense?
Despite the absence of rainfall, atmospheric moisture remained high, creating extremely humid conditions.
Strong solar heating, combined with elevated humidity levels, reduced the body's ability to cool itself through evaporation of sweat. Consequently, the "feels-like" temperature, or heat index, exceeded 40 degrees Celsius in several cities even when actual air temperatures were lower.
The prolonged dry spell also intensified the heat. As soils lose moisture, less solar energy is used for evaporation and more is converted into sensible heat, causing air temperatures to rise further. Studies conducted in India's core monsoon region have shown that this land-atmosphere interaction can significantly amplify heat during extended dry periods.
Will One Week of Rain Be Enough?
While the expected spell of rainfall is likely to provide immediate relief from the heat and improve conditions for farmers sowing crops such as rice, soybean, cotton and pulses, it is unlikely to eliminate the seasonal rainfall deficit on its own.
A meaningful recovery will require sustained and widespread rainfall over the coming weeks. As a result, the performance of the monsoon during August will play a decisive role in determining whether the season ultimately meets expectations or ends with a significant rainfall shortfall.
