An Intraseasonal Model for the Prediction of Atlantic and East Pacific Tropical Cyclone Genesis

Inspired by the work of Leroy and Wheeler (2008), a real-time logistic regression model is developed for the intraseasonal prediction of tropical cyclone genesis over the Atlantic and East Pacific Ocean regions using data from 1975 to 2009. The predictors used in the model include a climatology of tropical cyclone genesis for each ocean region, an El Niño-Southern Oscillation index derived from the first principal component of sea surface temperature over the El Niño 3 region, and two indices representing the propagating Madden-Julian Oscillation. These predictors are suggested as appropriate based on previous work in the literature and are further confirmed in this study using basic statistics. Univariate logistic regression models are generated for each predictor in each region to ensure the choice of prediction scheme. Using all predictors, cross-validated hindcasts are developed out to a seven week lag. A formal stepwise predictor selection procedure is utilized to select the predictors used in each region. Brier scores and reliability diagrams are used to assess the skill and dependability of the models.