Not Symmetric

Dwight writes:

HI Marc - Here is something on Fay that I found on the Weather Channel. Any thoughts?

The Weather Channel discussion (written by Stu Ostro) is interesting:

Within the past few hours, though (I'm posting this around 2:30 am EDT Monday), the most robust convective flareup the storm has had in a long time has sprouted, and it's spinning like a top as evidenced both by rapid scan infrared satellite imagery (in which images are taken every few minutes and looped) and the Key West radar.

At first it appeared as if this was one of two seemingly innocuous spins aloft, one on the west side of the center and one on the east. However, this eastern one has persisted, and it'll have to be monitored very closely given that it's not out of the question that the surface center relocates under the convection given how broad and weak the circulation was earlier.

My response:

Hi Dwight:

That discussion on the Weather Channel is very informative, and pertinent. Hurricanes are usually pretty axisymmetric, but tropical storms like Fay can have the center of circulation displaced considerably from the center of convection, creating an unsightly sloppy appearance, but making the storm susceptible to darting, unpredictable changes in direction, as the center of circulation will suddenly snap back to where the center of convection is.

I'm afraid that is what's happening right now with Fay. It's almost as if the storm is trying to hop over Cuba. All of a sudden, the storm looks like it is choosing some of the eastern paths I had hoped it would skip.

Currently, the NOGAPS model shows that the center of circulation will remain just off the western coast of Florida, and the center of convection will remain well on-shore. Then the storm moves south to north, raking the entire state with heavy rain.

If anything, the GFS model forecast is even more alarming. It carries the storm NNE across South Florida, hitting the Miami area quite hard, and perhaps clipping Tampa. Then the storm crosses back into the Atlantic near Jacksonville, strengthens, then comes westwards, crosses the Florida peninsula, clips Tampa a second time, before heading westward across the northern Gulf of Mexico, stopping, turning right, and plowing into the Mobile, AL area.

As much as dislike the GFS model, for this storm, it seems to have a better track record so far.

So, we will have to see. If Fay dallies too long, you might have to delay a return to Florida a second time.