Monsoon to hit Kerala on 30 May: IMD

The Indian Meteorological Department (IMD) on Friday announced that the southwest monsoon was likely to set in over Kerala on 30 May. The forecast was subject to a model error of plus or minus four days.

In a press release, the IMD also said the monsoon flow was expected to appear over the Andaman Sea by next week and cover the entire sea by 20 May, close to the normal date for the region.

The IMD's forecast of monsoon onset date is usually off by a few days. For example, last year, the IMD forecast a 26 May onset, but the monsoon arrived on 23 May. In 2008 the forecast was for 29 May and the actual date was 31 May.

Last month, the IMD forecast a normal rainfall for this year with a precipitation of 98 per cent of the long period average, subject to a model error of plus or minus five per cent for the entire season (from June to September) and for the country as a whole. However, it admitted that the regional rainfall could vary widely, and would have to be carefully watched. (See: Heat wave spells good monsoon, says weatherman)

Last year, the agency forecast a rainfall of 94 per cent plus or minus five per cent in April and then fine tuned it to 93 per cent plus or minus four per cent. But the country received a rainfall of just 78 per cent of the LPA for the season.

IMD experts said a normal onset need not necessarily mean that the rainfall would be normal for the season as a whole as the country was too huge and the season spread over a long period of four months. It took two months to even cover the entire country.