Franklin survives

Franklin has proved itself to be a survivor. The significant southwesterly shear from the tropical wave in the Caribbean has relaxed a bit as the two systems have moved farther apart--Franklin has moved to the northwest and the Caribbean wave has moved to the west-northwest. There is still some substantial shear from the Caribbean wave, but it should gradually lessen today. However, Franklin has another problem to worry about--the approach of a mid-latitude trough from the west. This trough has plenty of shearing winds of its own, and unless Franklin scoots quickly to the east ahead of the trough, he will be weakened or torn apart by the shear. NHC and the various forecast models all have different ideas of what will happen. The basic scenarios are:

1) Franklin gets picked up by the trough and scooted way out over the open Atlantic, as the GFDL and GFS models are predicting (40% chance).

2) Franklin will follow the official NHC forecast and move to the northeast away from land, then get overtaken by the trough and survive the shearing action of the trough. This would leave Franklin orphaned to await the next trough to sweep it out sea--or potentially come back and threaten the East Coast (30% chance).

3) Franklin will follow the NHC forecast as above, but get destroyed sometime in the next 3 days by shear (20% chance).

4) Franklin will turn due west and move over Florida as a weak tropical storm (9% chance).

It's situations like this one that greatly increase the average hurricane forecast track error. Emily was much easier to predict!

Meanwhile, the tropical wave over the Caribbean continues to look impressive, but is too close to the Yucatan Peninsula to develop much today. On Saturday, when it emerges over the Gulf of Mexico, it has a better chance of becoming a tropical depression. The latest GFS model run calls for it to turn into Tropical Storm Gert and hit the Mexican coast a few hundred miles south of where Emily came ashore.

Jeff Masters