New Saffir-Simpson Scale

With just over two weeks to go before the start of the 2009 Atlantic hurricane season, the National Hurricane Center (NHC) has confirmed it has removed storm surge risk from the Saffir-Simpson scale that ranks a storm based on its wind speed (see our recent April 1 posting). The NHC said the move is to help reduce public confusion about the impacts associated with the various hurricane categories as well as to provide a more scientifically defensible scale. Hopefully, it will also help homeowners understand why they need to buy a separate  flood insurance policy from the National Flood Insurance Program (NFIP). A separate probabilistic storm surge product is available on the NHC Web site showing where storm surge is likely when there is a hurricane watch or hurricane warning in effect for any portion of the Gulf or Atlantic coasts. Aimed primarily at emergency managers, the Tropical Cyclone Storm Surge Probabilities graphic shows probabilities in percent, of storm surge exceeding various thresholds. In 2009, the thresholds will include data at 1-foot intervals with a minimum value of 2 feet and a maximum value of 25 feet. The graphic is based on the Sea, Lake and Overland Surge from Hurricanes (SLOSH) model run by the NHC and takes into account pressure, size, forward speed, track and winds. Check out further I.I.I. information on flood insurance.

Leave a Reply

Your email address will not be published. Required fields are marked *