Rainfall across India during the southwest monsoon season will be normal for a third year in a row despite a slow start, according to the updated forecast released by the Indian Meteorological Department (IMD).

Rainfall over the country as a whole for the 2012 southwest monsoon season (June to September) is most likely to be normal (96-104% of LPA), the weather bureau said today. That is less than the 99% predicted in April.

Quantitatively, monsoon season rainfall for the country as a whole is likely to be 96% of the long period average (LPA) with a model error of ±4%, the IMD said.

The IMD defines normal monsoon rainfall as 96% to 104% of the LPA received between between 1951 and 2000.

The LPA rainfall over the country as a whole for the period 1951-2000 is 89 cm.

The cumulative seasonal rainfall over the country as a whole during the period June 1 to June 21 has been 76% of LPA.

Rainfall over the country as a whole for July is likely to be 98% of its LPA and that for August is likely to be 96% of LPA, the IMD said today. Both the forecasts are have a model error of ± 9%.

Over the four broad geographical regions of the country, rainfall for the 2012 Southwest Monsoon Season is likely to be 93% of its LPA over North-West India, 96% of its LPA over Central India, 95% of its LPA over South Peninsula, and 99% of its LPA over North-East India all with a model error of ± 8 %.

This year, setting in of southwest monsoon over Andaman Sea was delayed by about three days. It set in over Kerala on 5th June as against the IMD forecast date of 1st June ± 4 days.

On 6th June, it rapidly advanced mainly along the west coast and over northeastern States and covered entire Kerala, coastal Karnataka, Goa, southern parts of Konkan, Madhya Maharashtra, entire Arunachal Pradesh, Assam, Meghalaya, Manipur, Mizoram, Nagaland, Tripura and parts of sub-Himalayan West Bengal & Sikkim.

After a hiatus in the advance of monsoon for a period of about one week, on 13th June, the monsoon further advanced into some more parts of Madhya Maharashtra, interior Karnataka, most parts of Tamil Nadu, remaining parts of south Bay of Bengal and some more parts of central & north Bay of Bengal.

By 21st June, monsoon covered most parts of Arabian Sea, extreme south Gujarat, most parts of Maharashtra, entire Andhra Pradesh, Orissa, West Bengal & Sikkim, Chhattisgarh, Bihar, Jharkhand, Bay of Bengal and some parts of east Madhya Pradesh and east Uttar Pradesh.