Monsoon rains were 95 per cent of the long-term average compared with the India Meteorological Department or IMD's forecast of 98 per cent, marking the fourth straight year in which the IMD has overestimated likely rainfall.
Monsoon delivers about 70 per cent of India's annual rainfall. Rainfall was below average mostly because of low rainfall in the oilseeds and pulses-growing Madhya Pradesh and in rice-growing Haryana and Punjab.
While rice output is expected to be down 2 per cent compared with last year due to better irrigation in the rain deficient northern states, soybean output could fall about 8 per cent, the government said this week.
The IMD for the first time adopted the so-called dynamic model, based on a US model tweaked for India, to improve the accuracy of its forecasts.
IMD's forecast for the 2017 monsoon was its most accurate since 2008, when there was a difference of only 1 percentage point between the forecast and the actual rainfall.
The weather office was similarly accurate in 2011, when the difference was 3 percentage points.
(Reporting by Sudarshan Varadhan)