Tropical Storm Isaac continues to recuperate just off the eastern coast of Cuba this evening as a strong tropical storm with 60 MPH winds. There are more watches and warnings in effect than I could practically list, but here's the gist of it:
If you live in Florida south of Tampa, especially towards southwestern Florida, you will likely experience tropical storm force (45-73 MPH winds) winds. The Keys and extreme southern Florida are under a Hurricane Warning, meaning sustained winds in excess of 74 MPH are predicted.
The Florida Keys will take the brunt of this storm. I don't think I need to lecture anyone who lives there as to the risks of it all. There are tons of school/business/government closings throughout Florida, including the cancellation of the first day of the RNC, so be sure to check your local news for details.
The models are giving meteorologists hell in trying to predict the path of this storm. Here is the official NHC path for Isaac over the coming days. While I disagree with it, it is what it is:
The reason I disagree with it is because more and more models are starting to settle into the idea that Isaac will become a major hurricane (at or above Category 3 status) and make landfall somewhere between New Orleans and Pensacola, with Mobile (where I am) seemingly the favorite spot. They also don't like making major track jumps in their forecasts until a trend is almost glaringly obvious in the models, which leads to hesitation on their part.
The reason for the uncertainty and waffling right now is because of something called a subtropical ridge. It's essentially an area of high pressure over the western Atlantic Ocean right now, and the strength of this ridge, or high, will determine how much of an effect it will have on Isaac.
The stronger the ridge is, the more it will act to deflect Isaac from moving east, and it'll push it towards New Orleans/Mobile.
The weaker the ridge is, the more likely it is to start curving northeast into the Florida Panhandle and the southeastern United States.
The models are bickering (metaphorically, of course) over how strong the ridge will be. A small change in its strength could mean a big difference in how it steers Isaac in the coming days.
The consensus of the 18z (1PM CDT) spaghetti plot models still say that the storm will approach the Florida Panhandle near Panama City, and this is why the NHC has kept their forecast over to the east:
There's a really great weather site run by a meteorologist I was lab partners with in one of my meteorology classes called 28storms.com. He and the other folks who run the site are really, really good with this stuff, so I highly recommend following their site and them on Facebook.
But I digress. They shared the HWRF model on their Facebook page a little while ago, showing a major hurricane approaching the Mississippi Coast between New Orleans and Mobile:
As with all major weather events, this is a highly fluid and rapidly changing weather event. Anyone from New Orleans to Miami needs to keep an eye on Isaac over the coming days, and be prepared to take immediate action (up to and including a full evacuation) if necessary. Listen to your local authorities. Don't be an idiot and try to ride it out if you're in a threat zone -- if you do, there won't be anyone there to bail you out if something happens.
The NHC updates their track forecast every 6 hours (11AM/PM and 5AM/PM), with intermediate updates every 3 hours. Make sure to follow their forecasts as opposed to any one individual model.
National Weather Service San Juan PR
National Weather Service Tampa FL
National Weather Service Key West FL
National Weather Service Miami/South FL
National Weather Service Melbourne FL
National Weather Service Tallahassee FL
National Weather Service Mobile AL