Weather Nerd

Fay struggling; computer models split

Tropical Storm Fay is struggling a bit this morning, with no indication yet of significant intensification. Wind shear has unexpectedly increased, and may inhibit development somewhat. However, according to the National Hurricane Center’s 11am EDT discussion, “THE SHEAR IS STILL LIGHT ENOUGH FOR STRENGTHENING TO OCCUR IF FAY CAN DEVELOP AN INNER CORE.” As of now, though, no such core exists; the storm is disorganized and ragged-looking. If it stays that way, Fay may be fairly weak when she hits Cuba tonight, and even weaker when it emerges in the Florida Straits tomorrow morning.

The storm’s long-term track remains somewhat of a mystery. There is now an unusually well-defined split in the computer models, with some calling for the storm to track toward the central or western Florida panhandle, while others expect it to recurve fairly sharply and make landfall somewhere south of Tampa Bay. Remarkably, none of the models on the CSU “spaghetti” plot expect a landfall along the 300-mile-long stretch of coastline in between Apalachicola and Tampa:

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The National Hurricane Center favors the right-turn scenario. In fact, the official forecast track for Tropical Storm Fay has been nudged slightly to the right as of 11:00 AM EDT, and landfall is now predicted to occur very near where Hurricane Charley came ashore in 2004. That said, the “cone of probability” still encompasses most of the state, and everyone in that area should be preparing for a possible hit. The track forecast remains very uncertain and “low confidence.”

Thankfully, although the intensity forecast is also very uncertain, Fay is currently expected to be a Category 1 hurricane at landfall in Florida, not a Category 4 monster like Charley. And lay hurricane buff and weatherblogger Alan Sullivan — who plans to ride out the storm in Dania Beach, north of Miami on the state’s east coast — doubts it will get stronger than that:

Fay is not a big deal. In fact it will be fascinating for this weather nut: a tropical storm or minimal hurricane right in my vicinity, yet denied the dangerous vigor sometimes attained by cyclones over the local waters. Why? The storm’s history, its course, and its environment.

First, Fay was slow to develop, and just when it started to pull together, it passed over large chunks of land. Second, although a little stronger this morning, Fay must now take a diagonal route over Cuba before it can reach the Florida Strait. Third, upper winds in the northern Gulf resemble what one might see in early October. Fay will be sheered by the time it reaches the latitude of Tampa.

The course of the storm remains very uncertain, but overnight those hostile upper winds have dug even further south over the northern Gulf and northern Florida. This has caused many of the models to nudge the track of Fay further right. Landfall in South Florida now appears probable. The storm will have a brief opportunity to strengthen over the Gulf Stream in the Florida Strait. I see high likelihood that I will be live-blogging a borderline hurricane here tomorrow evening.

After landfall Fay should drift up the peninsula, weakening from friction and sheer. Yesterday’s declaration of emergency by Governor Crist was premature and panicky. This man has the disposition of an old Auntie — in fact he reminds me of Fargo’s one-time Republican mayor, Bruce Furness, who went completely to pieces during the 1997 flood. Let’s hope John McCain will not regard him as VP material.

Sullivan, incidentally, is dying of leukemia, and Fay could be his last hurricane. He writes in a poignant post this morning: “Live-blogging tropical storm Fay will be an adventure, and fortunately I have just enough strength left to deal with it, thanks to the current course of palliatives. But beyond remission comes the reality of the end game.” He then proceeds to discuss euthanasia and end-of-life issues which are beyond the scope of this blog, but I thought his situation, and discussion thereof, was worth a mention. In any case, Sullivan’s blog will definitely be worth watching over the coming days, as he “live-blogs” Fay’s approach.

Sullivan’s locale is currently under a Tropical Storm Warning. Meanwhile, Hurricane Watches have been extended north to Anna Maria Island, the southern mouth of Tampa Bay, as of 11:00 AM EDT. Also, the Florida Keys are now under a Tropical Storm Warning. These watch and warning areas will inexorably extend northward over the next day as Fay’s impact gets closer.

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