24 June 2012

Forecast Track For Debby: You’re On Your Own Son!

Posted by Dan Satterfield

Heavy Rains from Tropical Storm Debby are already impacting Central Florida.

The NOAA GFS Model says Florida...

Sometimes when I make a forecast, I know that it will be correct. I might miss the high or the low by a degree or two, but in general the weather will play out almost exactly as I expected. Then, there are those days when I know that it very likely will be just the opposite! Sometimes, I would just like to use that famous line from Blazing Saddles, “You’re on your own son!”

However, I must put together an on air forecast for the next 7 days, and this is the scenario the forecasters at the National Hurricane Center are facing today. They must make a forecast, but the uncertainty is extremely high…

Intensity forecasts are never easy, but sometimes you know in general where the system will be headed. The steering currents are so weak in the Gulf right now, that Debby could end up in Louisiana or Florida! Now, the NHC HAS to put out a forecast, and the odds are ever so slightly favoring Louisiana (as of now). A number of reasons for this, and perhaps chiefly is the European Center numerical model (the ECMWF) is forecasting that track, and has had superior performance compared to the American models in the past few years. That said, it does not always get it right. The NOAA GFS Model is also good and it says a turn toward Florida is most likely.

The ECMWF Model says Louisiana. They may both be wrong!

What I want you to take away from this is that there is very high uncertainty in where this system will go, so if you live along the Gulf, from Lake Charles to Tampa, assume that it may be headed your way.

I suspect we may see the guidance all pick a similar track within the next 24 hours but that may not happen until close to landfall. One other thing to not here is that of the currents stay this weak at landfall, we could be talking some incredible rainfall totals. Never forget, that it’s not the wind that causes the most destruction, and loss of life in a hurricane. It’s almost always the water (Hurricane Andrew being a notable exception).

Oh, and call me crazy, but I think Florida as of now…