Monday, June 1, 2009

Hurricanes Categorized By Wind Only

Monday, June 1 marks the first day of the 2009 Atlantic Hurricane Season. Activity is nil today in the tropics, but when we do get our first named, landfalling storm this year, you will notice some changes to the way forecasters describe possible impacts of a hurricane. Now, we will only refer to a category storm based on its maximum sustained winds. No longer will we categorize storms based on central pressure or possible storm surge. Check out the National Hurricane Center's Revised Saffir-Simpson Hurricane Scale.

This change is appropriate, considering the majority of landfalling storms have not caused the predicted storm surge for its category. Other factors impact storm surge, including the local shape of the coastline, the slope of the shelf leading up to the coast, the angle at which a storm makes landfall, and forward speed and size of a storm. The SLOSH model is one tool used to provide localized storm surge forecasts taking into account some of these mentioned factors.