According to the IMD release, India as a whole is likely to receive 96% of the south west monsoon from June to September 2023.
- There will be 96% of the Long Period Average (LPA) with a model error of ± 5% (Normal).
- The forecast is based on both dynamical and statistical models, and it suggests that quantitatively, the monsoon seasonal rainfall is likely to be 96% of the Long Period Average (LPA) with a model error of ± 5%.
- The LPA of the seasonal rainfall over the country as a whole based on data of 1971-2020 is 87 cm.
- Since 2003, India Meteorological Department (IMD) has been issuing the operational long-range forecast (LRF) for the southwest monsoon seasonal (June to September) rainfall averaged over the country as a whole in two stages.
- The first stage forecast is issued in April and the second stage or update forecast is issued by the end of May.
Factors effecting monsoon
- The northern hemisphere snow cover areas during February and March 2023 were observed to be below normal. Winter and spring snow cover extent over Northern Hemisphere as well as Eurasia has a tendency of general inverse relationship with the subsequent summer monsoon rainfall.
- La Nina conditions (cold phase) changed to Neutral conditions over the equatorial Pacific region.
- The latest MMCFS as well as other climate model forecast indicates that El Niño conditions (hot phase) are likely to develop during the monsoon season.
- At present, neutral Indian Ocean Dipole (IOD) conditions (difference in sea surface temperature between two areas) are present over the Indian Ocean and the latest Climate models forecast indicates that the positive IOD conditions are likely to develop during the southwest monsoon season.
