Monsoon Withdrawal Begins as Dry Air Enters Northwest India
Dry air is expected to enter northwest and western India after September 19-20, while a low-pressure system could delay the monsoon’s wider retreat.
The southwest monsoon is entering its final phase, with a large mass of dry air expected to move into northwest and western India after September 19-20. The influx could reduce atmospheric moisture and support the beginning of the monsoon’s withdrawal from the region.
Conditions are already becoming favourable for the retreat to begin from parts of West Rajasthan around September 19. As dry continental air replaces the moist monsoon atmosphere, rainfall activity is expected to gradually decline across northwest India.
However, the withdrawal may not happen uniformly across the country. A developing low-pressure system over central and eastern India could continue drawing moisture into these regions and sustain rainfall even as drier conditions spread across the northwest.
According to the forecast, the monsoon’s withdrawal from central and eastern parts of India could be delayed until around September 30. The retreat is expected to progress further after the low-pressure system weakens and dissipates.
The interaction between the incoming dry air and the low-pressure system will determine how quickly the monsoon retreats from the rest of the country. Normally, the withdrawal begins in northwest India before progressing towards central, eastern and southern regions as atmospheric circulation changes and moisture levels fall.
This year, the retreat could therefore occur in stages rather than as a continuous nationwide process. While northwest India may turn increasingly dry after September 19-20, parts of central and eastern India could continue experiencing monsoon rainfall through the latter part of September.
