katrina should be ashore in 24-30 hours. right now it's gotten about as strong as i'd reckoned it could.... there is some guidance making it a bit stronger, but i'd say more than half has it a bit weaker at landfall. there are no guarantees, either way... the ssts katrina is moving over can support a stronger hurricane, but by nature category fives don't tend to maintain themselves. of course, a bit weaker than a 140kt hurricane is not much of a favor. now, keep in mind that the fairy godmother can always intervene and knock 20-25kt off if the storm hits at the bottom end of an ERC. hurricanes also rarely maintain cat 5 status for more than a day or two. ivan kept going there, but never stayed very long. katrina will probably not be at category 5 at landfall, like the official says.. but there just isn't much to weaken the storm besides inner-core changes. no considerable shear in the forecast, and subsidence entrainment doesn't look to be a significant factor either. guidance hasn't really shifted.. so a direct hit on NO is quite possible. guidance won't shift significantly to the left.. the ridge-building and weakness don't support that kind of change, so it coming in at biloxi is more likely than, say, houma.
i'll just reiterate what many have already said on here. if you're in southeastern louisiana or coastal mississippi, staying behind could very well be a death sentence. if you're inland in some place like bogalusa or mccomb or laurel, you're still likely to get hurricane force winds... make sure you're in a sturdy structure tomorrow afternoon. significant wind impact will likely be felt as far inland as the starkville/columbus or even tupelo.. east of I-55, up towards northeast mississippi.
with a category 5 a day away from landfall on the central gulf coast, there shouldn't be other news.. but there is a little.
90L will operationally be a depression soon. it is around 15/47 right now moving wnw. the track should take it north of the caribbean, as the weakness left by 97L should draw it up a bit. most models take it up towards bermuda through a ridge weakness. 97L is a displaced low near 22/57 drifting west under heavy shear... trying to break through an upper trough. its convection is displaced well to the east and being drawn poleward.
a new invest will likely be issued by nrl as the last ssd cycle tagged the well-defined wave which left africa late yesterday as 91L. it's already rated 1.0 and starting at a low latitude... numerous models track and develop it, and take it as far as the western atlantic. it won't be nearing the caribbean until late in the week, if it develops.
HF 1427z28august