24 June 2012
Forecast Track For Debby: You’re On Your Own Son!
Posted by Dan Satterfield
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.
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…
Dan, the Sunday AM run of the Euro model is even more bizarre, as it takes it into Lower Alabama for a landfall…on Thursday! (I’d like to see that because it would bring Columbus, GA some good rain!)
Somewhere in Florida is as good a guess as any right now, though.
Yes the drought in Georgia could be relieved greatly by a good tropical storm. A slog as it stops at 5 inches or so!
Crutcher & Quayle’s climatology did a fair job with Debby.
If you’d like a pdf of the dozen or so most significant pages for the N. Atl – Gulf of Mex area, email me & I can forward it.
A few copies of the whole book can still be found online.
Crutcher, H.L., and R.G. Quayle, 1974: Mariners Worldwide Climatic Guide to Tropical Storms at Sea. GPO Stock # 003-19-00024-0, 312 pp. (Out of print, I think).
Indeed Rob! I’d like to see it.