Key West: mandatory evacuation

There's a church in Key West called the St. Mary's Star of the Sea Roman Catholic Church. In 1922, a nun built a "hurricane grotto" on the grounds of the church in memory of the 600 who died during the great Atlantic-Gulf hurricane of Sept. 10, 1919, a Category 4 hurricane that made a direct hit on Key West. The nun vowed that as long as the grotto stood, Key West would not suffer the brunt of another hurricane. Key West residents regularly make pilgrimages to the grotto to pray for protection from hurricanes. And so far, the grotto has worked--no Key West resident has died from a hurricane strike since the 1919 hurricane. I've heard from at least one Key West resident that plans to pay a visit to the grotto today, which I think is a good idea. A little divine intervention is what is needed this Hurricane Season of 2005. The current model runs were apparently not initialized last night with the "grotto factor", since they all show Rita's path taking the storm over or very near Key West. Still, the average error in a 24 hour forecast has been about 60 miles the past 10 years, so Key West may yet miss the brunt of this hurricane.

And a hurricane it will be. Satellite images show that deep convection has now wrapped all the way around the west side of Rita and into the center, where a complete eyewall is starting to form. Spiral bands from the storm are already visible on Miami long-range radar as Rita moves towards Florida and expands in size. Winds at George Town in the Bahama Islands were 37 mph, gusting to 57 mph at noon today. The 12:15 satellite intensity estimate from the University of Wisconsin was 991 mb and 68 mph surface winds. There won't be another hurricane hunter aircraft in the storm until 2pm EDT today, but I think we can anticipate that they will find a continuation of the strengthening trend observed today. Rita will be a hurricane by early this evening, and probably a Category 2 hurricane tomorrow. A 6 - 9 foot storm surge can be expected near and 50 miles to the to the north of where Rita's eye passes, and a foot higher if she hits near high tide (11am Tuesday). The surge plus the wind damage will cause hundreds of millions in damage in the Keys, but should cause no major loss of life, since I'm sure after Katrina residents of low-lying areas under evacuation orders will be compelled to comply more readily than usual. Key West and all of the lower and middle Keys were given a mandatory evacuation order this morning. This is a bit of a risky call by the emergency managers; They'll never get everyone out in time, and risk having people stuck on the bridges when the storm hits. Still, they have a lot of experience evacuating the Keys the past seven years, so hopefully it will go smoothly.


Figure 1. Expected maximum storm surge from Rita.

Rita in the Gulf
Once Rita emerges into the Gulf of Mexico, continued strengthening is expected, and she will likely attain at least Category 3 status by Wednesday. However, water temperatures over the middle of the Gulf of Mexico are 1 - 2C cooler than those near Key West, thanks to all the cold water stirred up by Katrina. This cooler water should not allow Rita to grow as strong as Katrina (not a very bold statement, considering Katrina was the 4th strongest hurricane on record!) Rita will probably grow to a Category 3, and has a chance at Category 4 status if she passes over the Gulf Stream loop current, an eddy of very warm water south of New Orleans near 26N latitude.


Figure 2.Sea Surface temperatures for Sunday, September 18. Note the cooler wake in the center of the Gulf left by Katrina.


Figure 3.Ocean heat potential for Sunday, September 18. The big red spot south at 26N 89W shows where the Gulf Loop Current is, a very deep eddy of warm water that will enhance intensification of Rita if she passes over it.

Where will Rita hit?
Take your pick of today's models runs:

GFDL: Central Louisiana (Houma)
GFS: Western Louisiana (Lake Charles)
UKMET: Eastern Texas (Galveston)
NOGAPS: South Texas (Corpus Christi)

Each set of model runs has moved the track of Rita progressively further east. The official NHC forecast has been following along, but staying further back. What we've seen so far this hurricane season is that when the models start trending this way, that's where the storm eventually winds up going. So my best guess is that Rita will hit Louisiana Friday as a Category 3 hurricane. What's the average error for a 5-day forecast? 270 miles. So, everyone from the Florida Panhandle to the Mexican border is still at risk.

Philippe
Philippe is slowly strengthening but heading northward out to sea. Philippe will continue to strengthen and head north, and is now not expected to affect any land areas, including Bermuda.

Wave between Africa and the Antilles
A large low pressure system is halfway between Africa and the Antilles islands. While this system does have a surface circulation and considerable deep convection, 15 knots of upper-level wind shear will keep this system from developing into a tropical depression for at least the next two days.

Jeff Masters