Abstract Author: Muthuvel Chelliah
Abstract Title: A probabilistic Atlantic hurricane activity forecast based on early summer atmospheric conditions
Abstract: A simple, yet purely objective, methodology for predicting the North Atlantic hurricane activity in a three tier system (above, normal, and below) as defined only by the standardized Accumulated Cyclone Index (ACE), will be described. The forecast will be based on observed atmospheric condition such as area averaged 200 mb stream function over the tropical Atlantic/African region and the area averaged vertical wind shear around the main development region during the months and season immediately preceding the peak of the North Atlantic hurricane activity. A review will be presented of the probabilistic forecasts for 1994-2008 Atlantic hurricane seasons that were made using NCEP/NCAR reanalysis data archive from 1949 until the year before the season for which the forecast was made. The motivation for the forecast method based on the tropical multi-decadal and ENSO modes of climate variability will be also be described.