Think we've got the reason behind the weakening down pat here...let me see if I can explain it pretty well.

Remember the upper low that had been located to the west of Frances as it traversed towards the Bahamas? Once it reached S Florida, it ceased movement and began to weaken, becoming nearly indiscernable on water vapor imagery. This was the status for a day or so, until yesterday.

Analysis of the visible and water vapor satellite imagery from yesterday shows that this weak upper low -- also reflected in the vorticity (spin) fields from the relatively high resolution RUC model -- and Frances completed somewhat of a Fujiwhara-type of interaction, leading to Frances moving northward for a time and then the upper low becoming entrained into Frances' circulation. Satellite showed that this upper low was entrained on the southwest side of the storm, moving around into the storm in a counterclockwise fashion. This is also consistant with the eyewall first breaking up on the SW side of the storm and later the erosion of the northeast eyewall and the dry slot to the west of the storm.

Essentially, Frances had lunch yesterday afternoon, ending up with an upset stomach. Now that it's had time to digest the low, it is back to strengthening over the open waters near the Bahamas. Recon should be out there shortly to provide a new fix; I imagine that a better defined eye and slightly lower pressure might be the end result. I don't expect any rapid or significant strengthening, but feel that the weakening trend is over.

Ivan is looking mighty healthy out in the E Atlantic today and is well on it's way to becoming a hurricane. Perhaps moving ever so slightly south of due west right now, it may well become a major hurricane in the next 3-5 days. as it approaches the islands. These "deep track" storms are often times the strongest ones, with climatological paths into Texas, Florida, or across many of the big islands, so it'll certainly be one to watch in the not-too-distant future. But for now...all eyes are on Frances.