SNL Gauges Isaac’s Potential Damage Impact

While the U.S. hurricane season has been relatively benign, it appears that Isaac could cause some damage, with the storm on course to hit Louisiana and continue upward through parts of Mississippi and Arkansas before weakening substantially.

A map of the storm’s predicted trajectory showed Louisiana receiving the most concentrated portion of the storm, with winds of between 74 mph and 110 mph. The NWS expects Isaac to slow down somewhat as it proceeds upward, although it will still have wind speeds of between 39 mph and 73 mph before it reaches central Arkansas.

Based on Isaac’s projected path, it will not be as strong as Katrina. The National Weather Service’s forecast does not show the storm gaining above 110 mph, whereas Katrina had maximum wind speed of around 125 mph when it made landfall in Louisiana. But that said, Katrina also started as a tropical storm, transferring to hurricane status right before making landfall near the Miami-Dade/Broward county line in Florida on the evening of Aug. 25, 2005.

Given Isaac’s strength, other less intense storms might provide better comparisons, such as Hurricane Lili in 2002. The Category 2 storm had wind speeds of around 100 mph when it hit New Iberia in southern Louisiana, according to a news release issued Oct. 17, 2002, by Insurance Services Office Inc.’s Property Claim Services unit. In that same update, ISO estimated that insurers would pay about $335 million to homeowners and businesses for insured property losses resulting from the storm.

Should Isaac prove a bit stronger, however, the impact might more closely resemble Hurricane Gustav or Hurricane Ike, which hit Louisiana in September 2008. Modeling firms estimated losses for each of those storms in the billions. For instance, RMS forecasted Sept. 1, 2008, that Gustav could lead to insured losses of between $4 billion and $10 billion, and on Sept. 17, 2008, projected that Ike could produce $7 billion to $12 billion in insured losses.

Source: SNL Insurance