Another powerful hurricane is shaping up to strike somewhere in the Gulf region by this weekend. The graphic above shows the position of tropical storm Rita on the far right, just north of the Eastern end of the Island of Cuba as of Monday, September 19th, 2005. Rita is position between a ridge of High Pressure in the north (Green) and a low pressure system to the south (blue) which all the computer models are projecting will allow Rita to slip through the Florida straits between Florida and Cuba and into the Gulf, becoming a catagory 3 hurricane by Wednesday (the red dot in the Middle of the Gulf). Strength projections are only made for three days, but it seems likely, given that the low pressure system in the Carribean is shifting Eastward, this will reduce what is called 'shear' and the forecasters are therefore calling for 'significant strengthening', so given the very warm waters in the Gulf this year, and the favorable conditions for hurricane development concurrent with Rita (since not only warm water, but shear is also important) it seems that Rita could continue to strengthen after Wednesday and become a catagory 4 or perhaps even a catagory 5 hurricane.
If the high pressure system over the Gulf states moves significantly towards the East, this will then cause Hurricane Rita to be steered into Louisiana , otherwise the Hurricane will make landfall on the Texas coast. The GFDL model is predicting signifcant weakening of the High Pressure system over the Gulf States steering Hurricane Rita to the right of the forecast range, resulting in another big hurricane hit for Louisiana by this weekend. It is worth noting here that computer models become less reliable after two or three days and thus are subject to errors when making long forecasts of hurricane behavior.
The NOAA describes the GFDL model as follows...
The GFDL Model is a full physics model, developed as a research tool at the Geophysical Fluid Dynamics Laboratory, that has become fully operational. With its fine resolution (about 19km) and other special adaptations to the hurricane problem, it has an excellent forecasting record.
Major metropolitan areas of Texas that may be threatened by Rita, include Houston, Galveston, which are close to the Louisiana border, and thus may be hit depending on how much the high pressure system weakens and moves out thus steering the Hurricane more to the left, while the GFDL model predicts a course not far from New Orleans, which would be a double disaster. It will be interesting to see how the American government reacts to the possible emergency evacuations which may become necessary sometime later on this week.