Probability Forecasts for User-Selected Precipitation Amounts
This forecast product, derived from IRI's issued probabilistic precipitation forecasts, shows the probability distribution in physical precipitation units (cm) for selected stations having long, publicly available observed monthly climate histories. The diagrams can be viewed either as a probability density function (pdf), or an inverse-cumulative "probability of exceedance" curve. The product provides tables showing probabilities not only of the three tercile-based categories, but probabilities of other numbers of climatologically equally likely categories, from 2 (lower vs. upper half) to 10 (decile-based categories). Perhaps most importantly, the product also provides calculations of the estimated probability of precipitation falling above or below any user-selected amount, or between two user-selected amounts. These products all represent a statistical downscaling of the large-scale precipitation probability forecast to an individual station on the basis of that station's historical precipitation data. View Product.