The latest experimental forecast based on the MMCFS suggests that there is a high probability for the 2020 monsoon season from June to September rainfall to be above normal to excess which is expected to be more than 104 % of LPA. Quantitatively, the 2020 monsoon rainfall is likely to be 107% of LPA with a model error of ±4%, predicts the weather forecast.
The updated forecast for the southwest monsoon season (June-September) rainfall all over the country as a whole was prepared by the India Meteorological Department (IMD) using a 6-parameter Statistical Ensemble Forecasting System (SEFS). The seasonal rainfall over the 4 broad geographical regions including NW India, NE India, Central India and South Peninsula and monthly rainfall for the July and August over the country as a whole has been prepared using Principal Component Regression (PCR) models with a different set of parameters.
Experimental forecast based on the Ministry’s Monsoon Mission Coupled Forecasting System (MMCFS) is also presented. The latest version of the high-resolution MMCFS implemented at the Office of Climate Research and Services, IMD, Pune was used for this purpose.
The second Stage Forecasts for the 2020 Southwest Monsoon Rainfall
Quantitatively, the 2020 monsoon season (June to September) rainfall for the country as a whole is likely to be 102% of the long period average (LPA) with a model error of ±4%. The Long Period Average (LPA) rainfall over the country as a whole for the period 1961-2010 is 88 cm.
The 5 category probability forecasts for the Monsoon Season (June to September) rainfall over the country as a whole is given below.
The probability forecasts suggest a very low probability (only 5%) for monsoon rainfall to be deficient. On the other hand, it suggests a very high probability for monsoon rainfall to be normal (41%).
Season (June-September) Rainfall over the Broad Geographical Regions
The 2020 monsoon season (June to September) rainfall is likely to be 107% of LPA over North-West India, 103% of LPA over central India, 102% of LPA over South Peninsula, and 96% of LPA over North-East India, all with a model error of ± 8 %. Thus, monsoon rainfall is expected to be spatially well distributed.
Monthly (July & August) Rainfall over the country as a whole
The rainfall over the country as a whole is likely to be 103% of its LPA during July and 97% of LPA during August, both with a model error of ± 9 %.