Third Successive Active Monsoon over Pakistan - An Analysis and Diagnostic Study of Monsoon 2012

In this research report an effort has been made to analyze and study main features of monsoon 2012 rainfall over Pakistan and its associated synoptic features. Monsoon 2012 was special due to the fact that it was the third consecutive monsoon, which recorded above normal rainfall. The seasonal monsoon 2012 rainfall of the country as a whole was 31 percent above long term normal (1961-2010) and is ranked 12th heaviest monsoon rainfall since 1961. The intensity of monsoon rainfall during the past two years (2010 & 2011) was 73% and 63% above than normal (1971-2000) respectively. The excessive monsoon 2012 rainfall, like monsoons of 2010 & 2011, again caused severe flash flooding in the country. The rainfall for month of September2012 was ranked highest ever recorded rainfall during the period 1961-2012. It was also recoded highest ever rainfall over Balochistan, second highest at Kyhber-Pakthunkhwa, third highest over Sindh and fifth highest over Azad Kashmir during past 52 years. It is investigated that the persistence of sea level monsoon trough over Central India that remained parallel to the latitudes, during second week of September 2012, caused weather systems which formed over North of Bay of Bengal/ northeastern parts of India to move westwards , resulting heavy down pour in the Southeastern parts of the country.