August 29, 2008
As of early this evening Hurricane Gustav is in the vicinity of the Cayman Islands and on a strengthening trend. Winds are currently at 80 miles per hour and there remains a much higher than normal probability that it will strengthen quickly during the next 24 hours. Check the National Hurricane Center website for the latest.
What follows are a few thoughts that I have had over the past few days. I have not been watching Gustav intently, (I’m still too busy returning to a normal life to have time for that), but I have been paying attention and the desire to publish my thoughts finally hit the threshold tonight.
After Tropical Depression Seven formed and became Gustav and the initial forecast pointed it to the Sunshine State, Florida residents collectively said, “No, we really don’t this.” Over the course of the next day the course shifted to suggest a general and later specific aim towards New Orleans.
It was at this point that coverage in televised media started to aggrevate me with inaccurate statements and hype. A local meteorologist (that really disappointed me when he said this as I respect him to the point of listening closely to what he says) made the ridiculous statement that the forecast track was similar to that of Katrina’s. While the forecast suggested the ultimate point of landfall as being similar, there was no chance of the track being similar because Katrina was never in the Caribbean. The Katrina talk was bothersome to me because it gave the appearance that the storm was a New Orleans problem when it actually was a storm that could potentially affect any of the Gulf coast.
Of course you can’t make Katrina comparisions on track alone, you have to compare on strength as well. Televised media has not failed here either as they breathlessly state that Gustav could become a category five hurricane. While it is true that it’s possible, it is not quite as probable as some make it out to be. The scenario is not quite as simple as ‘the storm will hit the hot water and it will go straight to category five, guaranteed’. Exceptionally favorable atmospheric conditions made that the case in 2005, that is not the case in 2008.
A pair National Hurricane Center forecast discussions on Wednesday had conclusions that made me wonder if they were concerned with the media coverage as well. There was this at 5:00 PM :
IT IS IMPORTANT TO NOTE THAT THERE STILL REMAINS SIGNIFICANT
UNCERTAINTY REGARDING GUSTAV’S ULTIMATE TRACK AT DAYS 3-5…AND IT
IS MUCH TOO SOON TO KNOW WHAT IMPACT THIS SYSTEM MAY HAVE ON THE
NORTHERN GULF COAST.
Followed by unusual candor at 11:00 PM
IT PROBABLY WOULDN’T HURT TO REMIND EVERYONE THAT THE AVERAGE 5-DAY
OFFICIAL TRACK ERROR IS ABOUT 300 MILES…AND THE AVERAGE 5-DAY
INTENSITY ERROR IS ABOUT 25 MPH.
Since Wednesday the forecast has shifted to the west a bit. Via Brendan Loy, I see that Jeff Masters issued a now is the time to get out of New Orleans message this afternoon. When one looks at the forecast situation and reads Masters’ words, it is clear that this on a very conservative ‘err on the side of caution’ basis. First his words:
…I don’t think Gustav is going to bring hurricane force winds to New Orleans, and I estimate there is 10% chance Gustav will bring a Category 3-level storm surge to the city. However, if I lived in the city, I’d get out tonight, because the storm is going to be plenty mean and is going to come uncomfortably close to you. A 10% chance is a big chance when it’s your life.
And second, the models at the time he was writing that:
(Plot provided courtesy of Jonathan Vigh, Colorado State University. For more information about this graphic, click here.)
The model providing the most concern to New Orleans was the GFDL, which was to the right (east) of the other models, but was (and continues to be on) a trend of shifting to the left (west). All other credible models suggest Gustav getting either as it possibly could without seriously harming New Orleans or being so far west that it is of no concern whatsoever.
I’m not sure I would have come to the same conclusion Dr Masters did. If I had to make a statement/give advice this afternoon it would have been, “If you don’t have a plan to get out, you are behind the curve and need to make a plan now. However, if it were me in New Orleans, I would hold out until the morning to review the situation before executing the plan.” Ultimately it’s a matter of risk tolerance, Dr Masters point is 10% (chance of catastrophic conditions), mine, possibly due to my relative youth and inexperience is a bit higher.
For residents of the central coast of Texas to the central coast of Louisiana, this will be a working weekend so that they are ready for Gustav’s arrival. They need worry about whether Gustav will be a category five, a category three is more than enough to ruin their day and they need to plan accordingly.