Break in the Monsoon

The monsoon does not blow as one unbroken, steady current through the entire rainy season. Instead, its activity comes in spells. There are periods when rain pours heavily for days, and then stretches when the rainfall weakens or nearly stops altogether. This alternation between wet and dry phases is a defining feature of the Indian monsoon, and the dry phase is what we call a break in the monsoon.

A break is essentially a pause in the monsoon's intensity. During the rainy season, the monsoon trough — the belt of low pressure that drives the wet spell — shifts its position. When this trough moves northward and sits close to the Himalayan foothills, the rainfall over most of the plains weakens considerably. This northward shift of the trough is the immediate cause of the break.

The most striking feature of a break is the sharp contrast it creates across the country. While the northern plains suffer from scanty rain, the Himalayan region and the northeastern states receive very heavy rainfall. At the same time, the southern parts of India, particularly the Tamil Nadu coast, also get good rain during this period. So a break is not a country-wide dry spell; it is a redistribution of rain, with some regions drying up while others get drenched.

The break in the monsoon is not a rare or accidental event. It occurs fairly regularly, and its duration is significant. On average, a break lasts for about a week or so. Because these breaks are a normal part of the monsoon's behaviour, they are also referred to as monsoon disturbances — a term that captures their role in disturbing the otherwise continuous rhythm of the season.