A few interesting notes...

1) Charley was the first cat. 4+ hurricane to make landfall in the U.S. since Hurricane Andrew in 1992.
2) Only 17 cat. 4+ hurricanes have made landfall in the U.S. since 1900.
3) The last four cat. 4+ storms to make landfall in the U.S.? Camille (1969), Hugo (1989), Andrew (1992), Charley (2004)
4) Only twice has the U.S. mainland *possibly* been impacted with two landfalling cat. 4+ storms since 1900 - 1906 and 1915. In 1906, it's debateable regarding hurricane #8 and the Fl. Keys; in 1915, it's debateable about the intensity at landfall of hurricane #2.

I post there partially because my major professor asked me if two cat. 4+ storms had ever made landfall in the U.S. in a year and partially because it's a scenario we could see play out over the remainder of this season, starting with Frances. It's a rarity folks, but it can happen.

Frances' eye looks to be becoming better defined on IR satellite imagery, although we're currently in satellite "twilight" for a couple of hours. We'll probably have a cat. 2 storm on our hands sometime tomorrow....well, today now. Outflow is excellent N to SW, becoming a little less defined on the S side. It's there on the east side, but is not nearly as well-defined as on the west side. It is moving into a region of very low shear - even less than what it was encountering, although it wasn't high to begin with - and despite mid-level dry air, precipitable water values are still high across the ocean, so further strengthening is likely.

It is interesting to note that a couple of models take the storm into the cat. 3-4 range within 5 days, most within 3 with a leveling in intensity beyond then. This includes some runs of the GFDL and the FSU Superensemble. The trends westward have stopped to some degree, and I think the current forecast track looks about right. If it slows as much as is forecast late in the period, Frances could be out there 10 or so more days. As is, somewhere around 8-10 sounds good.

The ultimate question will be how far to the west that the subtropical ridge builds over time, and how fast the storm moves in response to it. A faster storm will likely move further to the west with a stronger ridge. If the ridge builds to between Bermuda and the Outer Banks, a NC landfall or brush off the coast looks like a good bet. If it builds to the islands, then a NC/SC track looks like a better bet. If it builds inland a bit, then all bets are off.

The first scenario has played out the most times through history under these circumstances and tend to produce category 2 storms affecting the Wilmington to Cape Hatteras area; the last scenario has played out the least number of times but tends to result in strong storms affecting Florida, then getting into the Gulf and landfalling again between Lake Charles and Destin.

By all means though, it's one we're definitely going to have to follow.