HEAVY RAINFALL DISTRIBUTIONS BY SEASON IN LOUISIANA - SYNOPTIC INTERPRETATIONS AND QUANTILE ESTIMATES

In most studies, quantile estimates of extreme 24-hour rainfall are gi ven in annual probabilities. The probability of experiencing an excess ive storm event, however, differs throughout the year. As a result, th is paper explored the differences between heavy rainfall distributions by season in Louisiana. It was concluded by using the Kruskal-Wallis and Mann-Whitney tests that the distribution of heavy rainfall events differs significantly between particular seasons at the sites near the Gulf Coast. Furthermore, seasonal frequency curves varied dramaticall y at the four sites examined. Mixed distributions within these data we re not found to be problematic, but the mechanisms that produced the e vents were found to change seasonally. Extreme heavy rainfall events i n winter and spring were primarily generated by frontal weather system s, while summer and fall events had high proportions of events produce d by tropical disturbances and airmass (free-convective) conditions.