Any debate that wind damage was responsible for a majority Hurricane Irene losses — as opposed to publicly backed flooding — will likely be short lived given the nature of the storm.
“This event is going about inland rainfall and storm surge much more than wind,” says Matthew Nielsen, RMS’ senior project manager for its North American Hurricane Model. “The key questions will be around National Flood Insurance Program.”
Comparisons to the wind vs. water debate following Hurricane Katrina are completely misplaced, argues Robert Hartwig, Ph.D., president of the Insurance Information Institute.
“Following Katrina some of the houses were gone; washed away. People were wondering whether high winds or storm surge was responsible,” Hartwig explains. “The storm surge that happened in this event was not even remotely close Katrina. There is no similarity whatsoever.”
Many modeling firms are beginning to coalesce there results Irene’s flooding will be the primary loss driver. EQECAT issued a statement earlier Monday saying that rainfall “may become the most damaging component” of Hurricane Irene.
Nielsen adds that flooding from Hurricane Irene was exacerbated by several different factors, including the fact that the storm was large enough that rainfall began 12 to 15 hours before the storm made landfall.
“A large part of Irene remained over the ocean, so it didn’t fall apart and become post-tropical until it hit New England,” Neilsen says.
In addition, heavy rainfall throughout August in the region in New Jersey, New York and Vermont saturated the ground. This meant rain from Irene had nowhere to go but runoff into already overly swollen river and streams.
One area that private insurers may be vulnerable is fallen trees, a major issue in the Northeast following Irene and something that RMS follows within its model.
“When building the vulnerability portion of the model, we are able to take into account the main damage component from this type of storm is tree fall,” Nielsen says. “The amount of water makes it lot easier for trees to uproot.”
Although RMS does not have exact date on tree fall for Irene, Nielsen says that initial reports are that thousands of tree have succumb in several states.