Monsoon on backfoot: India records 28% rainfall deficit
What's the story
India's southwest monsoon is facing a major setback, recording a 28% rainfall deficit so far this season. The India Meteorological Department(IMD) data shows that between June 4 and June 14, the country received only 34.3mm of rainfall against the normal of 47.7mm. This has left large parts of central, eastern, and peninsular India with below-normal rainfall, while only a few areas have seen excess rain.
Weather disruption
Meteorologists attribute the slowdown to an unusual atmospheric pattern
Despite the monsoon's recent advance into southern and central India, meteorologists have attributed the slowdown to an unusual atmospheric pattern. The westerly jet stream, a fast-moving river of air in the upper atmosphere, has shifted farther south than normal. This shift is suppressing the upper-level easterly jet, which usually drives monsoon circulation across India.
Rainfall impact
Atmospheric pattern also affecting weather systems over Bay of Bengal
The unusual atmospheric pattern is also hindering weather systems over the Bay of Bengal from moving inland. Without a strong steering mechanism, these rain-bearing systems remain weak or are confined to limited areas instead of spreading moisture deep into the country. This has resulted in dry spells across central India, eastern states, and parts of the southern peninsula during what is usually a period of expanding monsoon activity.
Weather forecast
Rainfall deficit more severe than many seasonal forecasts anticipated
The current rainfall deficit is more severe than many seasonal forecasts issued in May had anticipated. Most long-range models had predicted a healthy start to the monsoon season, backed by favorable ocean conditions. However, an unexpected atmospheric obstacle has emerged instead. However, the El Niño effect was also forecast to adversely impact the monsoon this year.
Weather outlook
Hope for monsoon revival in late June
Despite the current challenges, there is some hope for the second half of June. Weather models suggest that the upper-level easterly jet could strengthen after June 20. If this happens, rain-bearing systems over the Bay of Bengal may start moving into mainland India again. This would allow monsoon to reorganize and spread more effectively across the country.