Hurricane Katrina

Post Landfall 6 | Summary
Posting Date: August 29, 2005, 10:30:00 AM

Because Katrina’s second landfall occurred more than 72 hours after Katrina left south Florida, AIR is providing two sets of event sets for Hurricane Katrina. One is for Katrina’s combined losses from the two landfalls, the second is for Gulf losses (second landfall) only. These are being provided together in zipped files for CATRADER and CLASIC/2. Upon unzipping, users will be able to access the two files, which are clearly labeled. At 7:10 a.m. EDT, Monday, August 29, Hurricane Katrina made landfall just south of Buras, Louisiana, as a Category 4 hurricane with maximum sustained winds of near 145 mph. As of 9:00 a.m. Katrina is located about 40 miles southeast of New Orleans and about 65 miles southwest of Biloxi, Mississippi. Katrina has maintained Category 4 status and is currently packing maximum sustained winds of near 135 mph with higher gusts. The storm is moving to the north at near 15 mph. A gradual turn to the north-northeast and a further increase in forward speed is expected during the next 24 hours. Hurricane Katrina grew in size throughout the day yesterday. Hurricane force winds currently extend outward to 125 miles from the center of the storm and tropical storm force winds extend outward up to 230 miles. This means that a large part of the northern Gulf coast will be affected by this storm. Storm surge of up to 22 feet can be expected near and to the right of the storm’s center, particularly along the Mississippi coast and into Mobile Bay. Damage reports are only just beginning to come in. However, at Category 4 wind speeds, wood frame homes can be expected to suffer extensive structural damage and mobile homes can be destroyed. Building codes in this part of the Gulf are not as stringent as in Florida and the building stock, particularly in historical New Orleans, is older and more vulnerable. Katrina’s winds will create tremendous suction forces on roofs, pulling off coverings and even structural members, while unprotected windows are likely to be breached by the impact of windborne debris. Awnings, balconies, carports and other non-structural, non-engineered building components will suffer significant damage. AIR will be sending engineering teams to the affected areas within the next several days to conduct post-disaster surveys. If there is good news, it is that Katrina weakened somewhat before landfall and turned to the north sooner than expected, taking it just east of vulnerable New Orleans. Katrina was a Category 5 hurricane for much of yesterday, with 175 mph winds and the fourth lowest central pressure on record for the Atlantic basin. While still a very powerful storm at landfall, a difference of 30 mph is significant in view of the fact that, above about 110, mph damage increases exponentially. The slightly more easterly track than had been forecast means that the densely-populated New Orleans metropolitan area will be on the left-hand, weaker side of the storm. While there are early reports of at least one levee having been breached and some pumps failing, it appears that the worst fears of widespread breaching of levees protecting the city may go unrealized. However, the more easterly track also means that Gulfport and Biloxi, Mississippi and points further east will feel the brunt Katrina’s winds and storm surge. Both “All” and “Select” event sets are provided for CATRADER and CLASIC/2 users. The “All” event sets contains hundreds of scenarios simulated for this event and are therefore the most appropriate method for estimating your potential losses. Sets of 11 specific scenarios, which are selected from the full event sets and represent the range of potential losses across the full industry loss distribution, are available under the “Select” event sets.

Post Landfall 6 | Downloads
Posting Date: August 29, 2005, 10:30:00 AM