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Many regions across Australia have high rainfall variability, which has various effects on water and food availability. This study examines rainfall patterns over consecutive 5-day periods during 1950-2013 using data from 92 observational stations in Australia. The first model used factor analysis to classify the stations into distinct geographical regions. Gamma generalised linear model (GLM) was then fitted to describe the rainfall amount in each category with season and year factors as the predictors. Factor analysis revealed eight factors, which represent eight geographical regions of Australia. Analysis of the similarities in the seasonal evolutions between regions revealed three seasonal rainfall groupings. The GLM models fitted the data quite well in all the areas and showed that 5-daily rainfall is significantly affected by the period of the year and its annual average in most of the regions. The models could be used to simulate rainfall data for the areas with inadequate rainfall records.

The presented study aims to classify precipitation regions, analyze trends, and fit an appropriate model for daily precipitation in Thailand. Factor analysis and generalized linear model (GLM) with gamma regression are performed on the historical records of daily rainfall amounts from 114 weather stations during 2001 to 2012. The study shows that the factor analysis divides the area of Thailand into seven regions with explanation of 58.9% of the total variance. The conducted gamma models reveal a good fit for the upper part, south-east, and south-west of the examined regions. The deviance residual plots from these models also provide a reasonable fit.