FSU Superensemble is restricted to the NHC, certain people at FSU, and anyone willing to pony up a ton of cash (think five digits).

Jeanne (et al.) synopsis...

Jeanne is currently along the south-southeast edge of a mid-level ridge of high pressure centered near the Delmarva peninsula. A gradual westward turn should begin to commence shortly. A vigorous longwave trough is currently situated over the Rockies but beginning to progress eastward as a ridge builds in just off of the northwest Pacific coast. A weak vorticity maximum is noted in northern Mississippi rotating along the western periphery of the eastern ridge, while a digging trough is analyzed along the eastern periphery of the ridge. The first piece of energy grabbed Karl and turned it northward; it may turn back towards the east for a short period of time before the next piece of energy, currently diving off of the eastern part of Canada, picks it up and turns it into the maritimes. A weak (and weakening) ridge is noted in the NW Caribbean with an upper low in the Bay of Campeche; this is establishing a region of upper-level diffluence around Ivan, enhancing the convection (but, at the same time, the upper low is providing some shear) and allowing the storm to return from the dead.

There are two scenarios that I can see playing out with Jeanne and the current set up.

The first keeps the ridge well-entrenched for the most part where it is now, allowing the storm to progress further westward into north central Florida before recurving along the periphery of the ridge. This is similar to the Frances path, although if this pans out, it is more likely the storm does not re-enter the Gulf at all and instead rides through Florida into Georgia somewhere east of Tallahassee, perhaps near Valdosta. In my opinion, this is the least likely of the two scenarios but feasible under the following situation: the piece of energy riding around the north side of the ridge is rather strong and could cause the ridge to become cut off -- essentially setting up an omega block situation. In any case, the ridge should erode a bit on the western side, allowing the storm to begin to turn near shore.

The other scenario does not involve the ridge becoming cut off from the flow and setting up a blocking pattern. This follows with the Canadian storm diving south, but just enough to pick up Karl and not enough to create a blocking situation. As it picks up Karl and the trough in the Rockies progresses eastward, the ridge should continue to move eastward, perhaps weakening slightly. This would allow Jeanne to travel westward initially, then turn somewhere offshore of Florida and affect the Carolinas. I feel this is the more likely of the two scenarios and would result in a target area between Cape Hatteras and Savannah.

Bottom line -- progressive pattern, Carolinas (with a close call for Florida); blocky pattern, Florida. I feel it's somewhere between 2/3 and 3/4 likely for the former, but reserve the right to change that. I do not feel that south Florida is in line for a landfall and also feel that the region from Jacksonville to Savannah will likely not see a direct impact but could see tropical storm force winds in either scenario. This isn't good for me, as I've got something to attend in Jacksonville Sunday night!

A good marker to get a grasp for this storm is the band of dry air on water vapor imagery that currently extends from Jeanne NW to Jacksonville and Memphis and onward around the ridge. This is essentially the periphery of the ridge as it stands, and also an inhibiting factor on the strength of Jeanne. Warmer waters lie ahead, although so do waters churned up by Frances. Shear should remain relatively low, but the dry air is keeping the storm in check and the overall structure appears to be a fairly stable one. The current intensity, give or take a few mph either way, is a good bet in the short-term with some slight weakening likely as the storm nears shore. Time frame we're looking at is late Sunday into early Monday, depending on which scenario pans out. Of course, further north equates to a later time.

My track forecast is similar to the last run of the GFDL, albeit a few miles further offshore, and is similar in nature to the NHC forecast. I do not have much to find fault with in the NHC forecast as-is, but can see the potential for the second scenario to pan out. We'll know more in a day or day and a half as to which way this is going to pan out; thankfully, things appear a bit clearer than they did in the past with this one.

And to think -- all at once, we have a loopy storm affecting the U.S. mainland, another loopy storm that has already affected the mainland redeveloping and doing something that is very likely unprecedented in the Atlantic basin, one (finally) well-behaved fish spinning Cape Verde storm, and a case where a storm and a disturbance are interacting, with the circulation associated with the storm and the convection associated with the disturbance combining forces to result in one overall system. And this is just the midst of the season -- let's not even go back into what's already taken place this year, nor look ahead to a potential Gulf/NW Caribbean season in the next month to month and a half.

Final word on Jeanne -- everyone from Palm Beach, FL northward to the Delmarva, due to the track potential, needs to watch where this thing is going. The highest probability areas are noted above, but no one is clear yet and regions not expected to see a direct landfall may likely see tropical storm force winds nonetheless.

Good night everyone...