Hurricane Dennis

Landfall | Summary
Posting Date: July 10, 2005, 6:00:00 PM

Hurricane Dennis made landfall as a Category 3 storm at 3:25 EDT this afternoon on Santa Rosa Island, about 20 miles east of Pensacola, Florida and almost exactly the location that Hurricane Opal made landfall in 1995. Wind speeds at landfall were estimated to be about 120 mph——enough to cause significant damage to mobile homes, roof coverings, cladding and awnings. Large trees are reported to be down in Pensacola and windborne debris from trees, signage and metal roofing continues to pose a threat to glazing. Rainfall amounts of between 5 and 10 inches are forecast for most of the Florida Panhandle and coastal Alabama, with isolated pockets of up to fifteen inches possible. Storm surge of 10-15 feet above normal tides has caused flooding along the coast near and to the east of the landfall location. More than 160,000 homes are without power in Alabama and Florida. After having weakened to a Category 1 hurricane yesterday as it interacted with the island of Hispanola, Dennis strengthened rapidly overnight, achieving wind speeds of 145 mph by early this morning. At one point, central pressure dropped 11 millibars in the span of one and a half hours. Moving into the somewhat cooler waters of the northern Gulf, however, Hurricane Dennis lost strength by the time it reached the Florida coast and was slightly weaker at landfall than last year’s Hurricane Ivan, which came ashore about 50 miles to the west. At the time of landfall, hurricane force winds from Dennis extended some 40 miles from the storm center——a much more tightly wound system than Hurricane Ivan. That, and the fact that Dennis made a last-minute wobble to the east, meant that Mobile, Alabama was largely spared the most damaging winds and any significant storm surge. Dennis was also a faster moving storm than Ivan. All of these factors, including the fact that Dennis made landfall along a somewhat less populated stretch of the coast, should prevent losses from reaching the levels achieved by Ivan——currently estimated at $7.11 billion by ISO’s PCS unit. As of 5:00 EDT, the center of Dennis was located about 20 miles north of Pensacola, Florida and moving almost due north at 21 mph. A north-northwest direction is expected to continue over the next several hours and the storm should slow. Dennis is now a Category 2 hurricane with maximum sustained winds of 105 mph and a central pressure of 950 mb. Hurricane force winds currently extend up to 25 miles from the center. The AIR tropical cyclone team has run scenarios using the latest information about the storm’s meteorological parameters, its landfall location and its forecast track, which are posted on the Scenarios page of this website. Please note that even after landfall there remains considerable uncertainty about the storm’s actual parameters and future track. On the Event Sets page, the “Select” event sets for CATRADER and CLASIC/2 are now available. These event sets are a set of 11 specific scenarios, which are selected from the hundreds of scenarios simulated for this event, and represent the range of potential losses across the full industry loss distribution. AIR continues to monitor Hurricane Dennis closely and will update the loss estimates after the storm has completed its track inland and dissipated. We will be dispatching a post-disaster survey team to the affected areas shortly.

Landfall | Downloads
Posting Date: July 10, 2005, 6:00:00 PM