re: Hurricane Florence - Catastrophic Flooding Potential

95L continues to fire deep convection tonight.



A weak tropical wave moved into an area of upper level divergence and that has allowed storms to fire the last couple of days. There is an Upper Low over the Yucatan that is helping drive this process.



The red circle highlights the ULL and the green circle is where we have seen deep convection firing.

At the surface, there appears to be a sharpening wave axis or trough but it is hard to tell without any recent ASCAT passes and few reliable surface observations.



The surface trough is highlighted by a kink in the low level flow. As this flow runs up against the Yucatan the trough can get kind of folded over allowing surface vorticity to increase. We have seen that today with steadily increasing vorticity at 850mb.



We have also seen increasing vorticity at 700mb and 500mb just down shear. This is a situation were shear can aid in development, since shear is helping drive deep convection. Deep convection is needed to consolidate the surface vorticity.

700mb



500mb



The NHC is currently giving this area a 60% to develop and that seems about right. I could see them going up to 70% with the 2:00 am update but they may wait until the full set of 00z model runs are in and make a move at 8:00am, if the models are aggressive with development.



The 12z Euro EPS was fairly aggressive with many members reaching TS.



We also saw an uptick on the 18z GEFS



An lastly, the experimental GFDL 3k hfvGFS. It shows the typical rolling fist in water vapor and then a TD/TS forming in the NW Gulf.