Isaac On Track for Florida, May Disrupt RNC Convention

By Andrew Freedman

All eyes are on Tropical Storm Isaac as on Wednesday it was moving into the eastern Caribbean Sea, and forecast scenarios include the possibility that it may hit Florida next week, potentially disrupting the Republican National Convention, which is set to begin Monday in Tampa. Southern Florida is now within the “cone of uncertainty” track forecast issued by the National Hurricane Center (NHC)  in Miami. Those forecasts indicate that by early next week, what at that time could be Hurricane Isaac, may pass close to or over parts of Florida.

The five-day forecast track for Tropical Storm Isaac, issued by the National Hurricane Center. Click on the image for a larger version.
Credit: NHC.

Recent computer model simulations have shifted the longer-range track forecast westward, making a run up the eastern seaboard less likely, and a landfall in Southwest Florida or a track into the Gulf of Mexico more plausible.

As of Wednesday morning, Isaac was a tropical storm with maximum sustained winds of 45 mph. It was moving west towards the island of Guadaloupe. The center of Tropical Storm Isaac is forecast to move through the Leeward Islands Wednesday evening, pass near or south of the Virgin Islands and Puerto Rico on Thursday, and near the Dominican Republic on Thursday night and Friday, the NHC said. The storm is expected to intensify into a hurricane within the next 24-to-48 hours, although current forecasts limits the storm’s intensity to Category 1 strength on the Saffir-Simpson Scale during the next four days, mainly due to interactions with the mountainous terrain of Hispaniola and Cuba. However, NHC forecasters wrote in an online forecast discussion that Isaac could strengthen once it passes over the warm waters between Cuba and Florida or the Gulf of Mexico.

Based on the forecast, various watches and warnings have been issued for islands including Puerto Rico and the Dominican Republic, and the National Hurricane Center is warning residents of Haiti and Cuba to pay close attention to the storm.

It is not unusual for Florida to be facing a hurricane threat at this time of year, since the most active period of the Atlantic hurricane season runs from mid-August to mid-September. This week is also the 20th anniversary of Hurricane Andrew, which was the last Category 5 hurricane to strike the U.S. Hurricane Andrew came ashore just south of Miami on August 24, 1992.

Computer model projections for Tropical Storm Isaac, as of Wednesday morning, August 22. Click on the image for a larger version.
Credit: NCAR.

As Climate Central reported in June, Tampa, which is located on the west coast of Florida,  is one of the most vulnerable cities to hurricane-related storm surge flooding, and has not suffered a direct strike from a strong hurricane since way back in 1921, when a storm surge of 10.5 feet occurred in Tampa Bay. A storm surge of that magnitude today would inundate tens of thousands of homes in the Tampa-St. Petersburg area.

However, it’s far too early to predict the actual path that Isaac will take, as well as how strong the storm will become, especially considering that the Hurricane Center’s average track error for a five-day forecast is about 200 nautical miles.