[StBernard] G.O.P. outlook fm Weather Underground

Westley Annis Westley at da-parish.com
Wed Sep 19 19:28:55 EDT 2007


Jeff Masters' blog update:

No development of 93L is expected until the surface circulation emerges off
the Gulf Coast of Florida Thursday.

Once 93L emerges into the Gulf of Mexico Thursday, all of the models
indicate the storm will intensify. This is a very complex forecast
situation, since the storm is starting out with the cold core of an ordinary
non-tropical low pressure system, and will transition to a warm-cored
tropical storm. The transition to a warm core system will probably take at
least a day. A storm undergoing such a process cannot intensify rapidly
while this is occurring. This means that if 93L hits New Orleans Friday
night/Saturday morning as the GFS and GFDL models are predicting, the storm
will likely still be below hurricane strength--as predicted by the 8am EDT
run of the SHIPS intensity model--or a minimal Category 1 hurricane--as
predicted by this morning's 06Z run of the GFDL model. I think a tropical
storm is more likely. Such a track would take it just north of the high heat
content waters of the Loop Current in the central Gulf of Mexico (Figure 2).
If 93L takes a more southerly track as the ECMWF and NOGAPS models predict,
it will have an extra day over water, and more time to firmly establish a
warm core. A warm core, fully tropical system is capable of must faster
intensification rates. A more southerly track would also take the storm over
the high heat content waters of the Loop Current, further aiding the
transition to a warm core system. Texas could see a Category 1 or 2
hurricane on Sunday in this scenario. Slowing down the intensification will
be the presence of plenty of dry air to the northwest, however, and a
tropical storm may be all that Texas would see.

The NOAA jet is scheduled to fly this evening and collect data to help with
the Wednesday evening (00Z Thursday) model runs. The first Air Force
Hurricane Hunter mission is scheduled for Thursday afternoon.

Spaghetti models:

http://www.wunderground.com/tropical/tracking/at200793_model.html


Jim





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