ATL: FIONA - Post-Tropical - Discussion

[IsabelaWeather]

To my eye, it looks like shear has lessened. The huge thunderstorms still pumping up are still moving west with the CoC. I wonder what this will do to the storm by the 11pm Advisory.

[tolakram]

[REDHurricane]

Big burst of convection near what appears to be the LLC, it will be interesting to see whether or not this leads to increased organization at the currently not-so-pretty upper levels of the storm. Like others have said, the lower levels have maintained vorticity throughout this period of stronger shear, but I'd imagine it would take another two to three days at least for everything to kind of stack up again, right? So I still remain very skeptical of the GFS forecast of this developing into a sub-980mb hurricane within just about three days from now -- until Fiona actually begins to show signs of strengthening I will lean towards the weaker/more westerly short-term path verifying as opposed to the stronger/out-to-sea path that the models are apparently favoring as of right now.



850mb vort


500mb vort


GFS 18z run at +72 hours

[BobHarlem]

 https://twitter.com/NWSSanJuan/status/1570942735716327424

[skyline385]

Fiona decided to wake up huh

[aspen]

Fiona decided to wake up huh

https://i.imgur.com/ikuxGMw.jpeg

It’s actually running 6-12 hours ahead of the 18z HWRF in terms of its convective structure. It still had Fiona looking kinda anemic with small hot towers are late as 06z tomorrow morning. This could lead to a temporary intensification phase before Hispaniola like on the HWRF and HMON…but no way we’re getting a hurricane this early, even if it’s brief.

[Sciencerocks]

[CrazyC83]

With the 60 kt forecast intensity just before the Dominican Republic landfall, I'd personally hoist a Hurricane Watch for the southern and eastern coasts.

[skyline385]

Lots of activity in the last few hours along with expansion of cold tops, might get dangerous for PR and DR at this rate

[Hurricane Mike]

With the 60 kt forecast intensity just before the Dominican Republic landfall, I'd personally hoist a Hurricane Watch for the southern and eastern coasts.

Yeah it's probably coming later Saturday.

[ThetaE]

Lots of activity in the last few hours along with expansion of cold tops, might get dangerous for PR and DR at this rate

https://s5.gifyu.com/images/goes16_ir_07L_202209162225.gif

The band of convection to the SW of the LLC is an especially big change from the past few days. Shear is not enough to keep Fiona asymmetric, currently.

[BobHarlem]

Lots of activity in the last few hours along with expansion of cold tops, might get dangerous for PR and DR at this rate

https://s5.gifyu.com/images/goes16_ir_07L_202209162225.gif

The band of convection to the SW of the LLC is an especially big change from the past few days. Shear is not enough to keep Fiona asymmetric, currently.

Between that and the 0z gfs showing it reaching hurricane strength right before PR, I wonder if hurricane watches (at least) should go up for PR and DR.

[Teban54]

The convective burst and the 1000mb pressure from recon may suggest Fiona is finally getting her act together, IMO. Shame no one is watching anymore when Florida becomes more likely to be in the clear.

[Landy]

It would appear Fiona is taking another dip southward again tonight, according to VDMs. Already almost half a degree south of where NHC had it marked at 11.

[AtlanticWind]

The convective burst and the 1000mb pressure from recon may suggest Fiona is finally getting her act together, IMO. Shame no one is watching anymore when Florida becomes more likely to be in the clear.

I am watching( from Florida) and yes seems to be getting its act together tonight
As for being in the clear I think Florida may be , but Bahamas are not and also
until I see it make that turn I never turn my back on storms.

[SconnieCane]

A reminder you can get some really bizarre tracks in the eastern Caribbean. It's not always a nice pretty WNW arc followed by a gradually sharpening rightward bend to the NW, N and NE. Matthew was down almost on the coast of South America and then shot straight north across western Haiti before bending back to the west, scraping Florida and hitting SC. Fiona is currently located roughly where Maria was in 2017, coming in south of where Irma had been a couple weeks earlier (and right through Hebert Box #1) yet it missed the CONUS. It's all very sensitive to the trough/ridge timing and the models don't usually get a good handle on that more than a few days out.

[AtlanticWind]

One other thing that concerns me slightly and is very worrisome for Hispaniola is
if this doesnt turn before the big Island I have seen a lot of storms interact with Hispaniola
and they often seem to get pulled west as the center gets disrupted.

If this ends a little further west and weaker I wonder if that will change the model output
at that point.

Also unfortunately would mean heavy rains for DR/Haiti

[CrazyC83]

One other thing that concerns me slightly and is very worrisome for Hispaniola is
if this doesnt turn before the big Island I have seen a lot of storms interact with Hispaniola
and they often seem to get pulled west as the center gets disrupted.

If this ends a little further west and weaker I wonder if that will change the model output
at that point.

Also unfortunately would mean heavy rains for DR/Haiti

In general, the weaker/more disrupted tracks are farther west, and if it slides beneath Hispaniola then all bets are off.

[drezee]

 https://twitter.com/andretrotter/status/1571009417075892225

[galaxy401]

Fiona is starting to look increasingly dangerous over there. Hurricane is within the realm of possibility tomorrow if she keeps this up.