Revival of monsoon likely after dissipation of cyclone

The southwest monsoon, which made a weak onset, still remains sluggish in the State with the majority of metrological subdivisions recording over 60% deficit rainfall.

The southwest monsoon, which made a weak onset, still remains sluggish in the State with the majority of metrological subdivisions recording over 60% deficit rainfall.

“The current weather models do not favour the strengthening of the monsoon at least for the next week. We hope once Cyclone Biparjoy completely dissipates after landfall, the synoptic conditions favouring the revival of monsoon will be on track,” says a scientist with the India Meteorological Department (IMD).

The offshore trough from Gujarat to Kerala, one of the semi-permanent systems during the monsoon season, is not active due to the disturbance of the cyclone, which has weakened the progress of the monsoon.

“There are four semi-permanent systems during the monsoon period - Mascarene High, monsoon trough from Ganganagar to Sagar island in the Bay of Bengal, heat low over northwestern India, and offshore trough from Gujarat to Kerala coast. Of these, only two are active – Mascarene High – a high-pressure area off the coast of Madagascar from where the monsoon wind originates with the wind blowing in an anticlockwise direction – and heat low, while the other two are not active due to the cyclonic disturbance. We hope by next week, monsoon will revive with the formation monsoon trough that runs from Kerala to Gujarat coast,” he says.

The IMD also forecasts below-normal rainfall in Kerala till June 22. However, there will be some progress after June 18, say officials. 

Of the 14 districts, the rain was ‘large deficient’ (a shortfall of 60 to 99%) in eight districts and Mahe and ‘deficient’ (shortfall of 20 to 59 %) in five districts. Only Pathanamthitta received normal rainfall till today. 

Kerala was to record normal rainfall of 280.5 mm rain in the first two weeks of June, while it received only 126 mm rain till June 14, a shortfall of 55%.