Although the storm has weakened to an open trough, this does not rule out the possibility that it could regenerate once conditions improve. Depending on the details how this happens, it could be classified as 6/Franklin or maintain 5/Emily. To pull from a a 6-year old advisory written by Stacy Stewart at NHC:
THE NWS RULES GOVERNING THE NAMING OF TROPICAL CYCLONES SPECIFY THAT...WITHIN A BASIN...WHEN A CYCLONE FORMS FROM THE REMNANT OF A PREVIOUSLY EXISTING CYCLONE...THE OLD NAME/NUMBER IS RETAINED. TROPICAL DEPRESSION TWELVE HAS A COMPLEX GENESIS THAT LIKELY INCLUDES A MID-LEVEL REMNANT OF FORMER TROPICAL DEPRESSION TEN. A REVIEW OF SATELLITE AND RAWINSONDE DATA OVER THE PAST WEEK OR SO SUGGESTS THAT A SECOND DISTURBANCE APPROACHED AND COMBINED WITH THE MID-LEVEL REMNANT OF TROPICAL DEPRESSION TEN ON 20 AUGUST. BECAUSE IT IS IMPOSSIBLE TO DETERMINE WHICH OF THESE TWO SYSTEMS IS ASSOCIATED WITH TODAY'S GENESIS...WE HAVE ELECTED TO USE THE DESIGNATION TWELVE RATHER THAN TEN FOR THE NEW DEPRESSION. THIS SITUATION DIFFERS FROM LAST YEAR'S REGENERATION OF IVAN...IN WHICH THE LOW-LEVEL REMNANT OF THAT SYSTEM REMAINED A DISTINCT FEATURE THAT COULD BE FOLLOWED CONTINUOUSLY UNTIL IT REGENERATED.
So in this case from 2005, TD10 dissipated, and after careful analysis, the new circulation that formed from its remnants did not have enough of TD10 in its gene pool to keep the same name. TD12 was classified as a new system from the remnants of TD10 (TD11 had formed elsewhere in the meantime). Incidentally, TD12 would eventually hit southern FL as Tropical Storm Katrina and then the northern Gulf coast as Hurricane Katrina.
Many models do re-develop this storm, and the track passes over the Bahamas on Friday and Saturday, then recurving out to sea before reaching Florida. The forecast intensity spread in 2 days (near closest approach to FL) is anywhere from 25-60kts for the models that re-develop it, and of course nothing for those that don't.
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