Skymet, India’s leading weather forecasting, and agriculture risk solutions company has released its monsoon forecast for 2021. Skymet expects the upcoming monsoon to be ‘healthy normal’ to the tune of 103% (with an error margin of +/- 5%) of the long period average (LPA) of 880.6mm for the 4-month period from June to September. This would make it 3rd consecutive year of normal or above-normal monsoon.
Now, Skymet has released its monsoon onset date for 2021. Skymet expects the onset to be around the normal date. Based on the data from 1961-2019, the normal date of onset over the Indian mainland is 01 June with a standard deviation of one week.
The onset of the Southwest Monsoon over Kerala is largely influenced by the oceanic conditions, both in the Arabian Sea and Bay of Bengal. Likely cyclone formation in the Arabian Sea will be consequential for the advance of monsoon stream over Indian waters. However, tropical storm 'Tauktae' will vacate the Indian region by May 22, 2021 following which the westerly winds and cross-equatorial flow will strengthen over the Arabian Sea. This also will be assisted by the MJO (Madden Julian Oscillation) entering the Indian Ocean with moderate amplitude. Pre-monsoon showers will be intense and hefty over Kerala.
Skymet predicts that this year the onset of southwest monsoon over Kerala is likely to be on 30 May 2021 with a model error of +/- 2 days.