Abstract
Pakistan experiences the southwest monsoon normally from July to September every year. In this paper, we analyse the effect of monthly rainfall for the months of July, August and September on overall seasonal monsoon for the period of 1960-2006 across 37 different meteorological stations of Pakistan. The statistical results are based on the notion of conditional probability. We find conditional probabilities of seasonal monsoon to be in excess, deficient and normal when the monthly rainfall of July, August and September is considered to be in excess and deficient. When rainfall in the months of July and August is in excess the seasonal monsoon behaviour is also likely to be in excess and probabilities of seasonal monsoon to be deficient are zero for most of the meteorological stations. Similarly, when rainfall in the months of July and August is considered to be deficient the seasonal monsoon behaviour is also likely to be deficient and probabilities of seasonal monsoon to be in excess are zero for most of the meteorological stations. (c) 2013 Royal Meteorological Society