Ocean-atmospheric interactions, heavy precipitation, and hurricane predictive index (HPI) associated with land-falling Hurricane Irene over the eastern coast of the United States

Hurricane Irene's deepest strengthening occurred during August 24th-25th, as it passed over the warm waters of the Bahamas and Gulf Stream whose SST's reached 30.5° C. Irene reached category 3 status by August 24th. By August 27th, the storm made landfall over North Carolina [2], eTRaP data provided estimated precipitation totals of 1" to 5" around the eye, however, using TRMM satellite data, precipitation totals were 5.9" to 8.9" over the northeastern coast of the US where the eye passed. The conditions that surrounded Irene's rainfall totals were surmised to be a result of strong ocean-atmospheric interactions over the Bahamas during its peak intensification period: August 23rd - 25th. To support this hypothesis, heat fluxes and vertical motions were derived over the entire period of Irene's existence. August 20u - 29th, using atmospheric data and soundings. Heat fluxes, HPI, and vertical motions were found to peak on August 23rd and remain consrstently high.