GUWAHATI, June 14 � The India Meteorological Department (IMD) has predicted that the monsoon rainfall over the NE region this time is likely to be normal or above normal.
The IMD in its Long Range Forecast for the current South West (SW) monsoon said that monsoon rainfall over the NE region is likely to be 99 per cent of the long period average (LPA) with a model error of plus-minus 8 per cent. The IMD LPA is based on the rainfall data available between 1951 AD and 2000 AD.
The IMD LRF of rainfall for NE India during the current SW monsoon states that there is 33 per cent probability of below normal rainfall, 37 per cent probability of normal rainfall and 30 per cent probability of above normal rainfall activities over the region. This suggests that the region is likely to experience normal or above normal rainfall during the current monsoon.
It needs mention here that the IMD LRF has referred to NE India as comprising the States of Arunachal Pradesh, Meghalaya, Assam, Nagaland, Manipur, Mizoram, Tripura, Sikkim, West Bengal, Bihar and Jharkhand.
Contrary to the above scenario, the LRF states that the forecasts from most of the national and international centres indicate that the rainfall of the 2014 monsoon season, � that is, June to September, � averaged over the country as a whole, is likely to be below normal.
Again, the LRF for the 2014 monsoon pointed to the fact that the Earth System Science Organization of the Union Ministry of Earth Sciences and the Indian Institute of Tropical Meteorology coupled dynamical model predicts moderate El-Nino conditions in the Tropical Pacific for summer months.
Almost all ensembles, barring one, predict warm Sea Surface Temperature conditions in the Nino 3 and Nino 3.4 � that is, Equatorial Pacific region. This provides confidence that the chances of El-Nino occurring during monsoon are very high, that is �more than 70 per cent, asserts the IMD in its LRF.
Moreover, conditions in the tropical Indian Ocean are warmer than normal, uniformly throughout the basin, and, it thus rules out any possibility of positive Indian Ocean Dipole conditions in the tropical Indian Ocean during the monsoon season, says the IMD.
It further states that in the North-West region of the country, the seasonal rainfall is likely to be 85 per cent of the LPA. The monsoon rainfall in the central part of the country this year is likely to be 94 per cent of the LPA, while it is likely to be 93 per cent of the LPA over the South Peninsula with the model error of plus minus 8 per cent.