Major Hurricane Fiona

[WxWatcher007]

Tropical Storm Fiona Discussion Number   5
NWS National Hurricane Center Miami FL       AL072022
1100 AM AST Thu Sep 15 2022

Moderate westerly shear continues to displace Fiona's deep
convection about a degree to the east of the low-level center, with
convective cloud tops as cold as about -80 degrees Celsius.
A recent ASCAT pass showed a solid area of 40- to 45-kt winds, and 
with the scatterometer's known undersampling characteristics, it's 
not out of the question that Fiona's intensity could be a little 
higher. For now, the initial intensity will be held at 45 kt, 
pending additional data from an Air Force Reserve Hurricane Hunter 
aircraft that is scheduled to investigate the storm this afternoon.

Moderate shear, generally out of the west, is expected to continue 
for much of the forecast period.  That in itself should suppress 
significant strengthening, but it may not be enough to prevent any 
strengthening at all.  Fiona's current intensity is a testament to 
its resilience in the face of the shear it has experienced over the 
past 24 hours.  There has been a general uptick in the intensity 
guidance after 48 hours, and the new NHC intensity forecast has 
been nudged upward during that time.  It is important to note, 
however, that the official forecast still lies below the IVCN, 
HCCA, and FSSE consensus aids from day 3 onward, and additional 
adjustments to the intensity forecast could be required in 
subsequent advisories if these trends continue.

Strong low- to mid-level ridging over the western Atlantic is
steering Fiona due west, or 270 degrees at 12 kt, and this general
motion, with some gradual decrease in forward speed, is likely to
continue for the next couple of days.  There is notable model
divergence after 36 hours, with the stronger GFS, HWRF, and HMON
solutions turning a slower Fiona northwestward over the northern
Leeward and Virgin Islands.  On the other hand, the ECWMF, UKMET,
and all of the consensus aids maintain a faster westward to
west-northwestward motion across the far northeastern Caribbean Sea
through day 3.  Given the expectation that moderate shear is likely
to continue, the NHC track forecast favors the less-intense
scenarios and shows a solution moving just south of the Virgin
Islands and then near Puerto Rico in a few days.  After day 
3, a weakness near the western extent of the ridge should allow 
Fiona to gain some latitude and possibly turn toward the northwest, 
moving across the Greater Antilles into the far southwestern 
Atlantic.  On the whole, the NHC track forecast remains steady from 
previous predictions, largely following a blend of the TVCN and HCCA 
consensus aids.

Additional watches or warnings will likely be required later today 
for portions of the Leeward Islands, Puerto Rico, and the Virgin 
Islands, and interests in these locations should monitor the latest 
forecast updates.


Key Messages:

1. Tropical storm conditions are expected in portions of the
Leeward Islands within the warning area by Friday evening.  
Tropical storm conditions are possible in portions of the Leeward 
Islands within the watch area by Friday night.

2. Heavy rains from Fiona will reach the northern Leeward Islands 
Friday afternoon, spreading to the British and U.S. Virgin Islands 
and Puerto Rico Saturday into Sunday morning, and reaching eastern 
Hispaniola Sunday.  This rainfall may produce flash and urban 
flooding, along with isolated mudslides in areas of higher terrain.

3. Fiona is expected to move near the Virgin Islands, Puerto Rico,
and Hispaniola this weekend and early next week, and watches will 
likely be issued for some of those areas later today.


FORECAST POSITIONS AND MAX WINDS

INIT  15/1500Z 16.6N  54.3W   45 KT  50 MPH
 12H  16/0000Z 16.6N  56.2W   45 KT  50 MPH
 24H  16/1200Z 16.7N  58.7W   45 KT  50 MPH
 36H  17/0000Z 16.9N  61.2W   50 KT  60 MPH
 48H  17/1200Z 17.2N  63.4W   50 KT  60 MPH
 60H  18/0000Z 17.5N  65.2W   50 KT  60 MPH
 72H  18/1200Z 17.8N  66.6W   55 KT  65 MPH
 96H  19/1200Z 19.3N  68.6W   55 KT  65 MPH
120H  20/1200Z 21.5N  70.4W   60 KT  70 MPH

$$
Forecaster Berg

 

[GaWx]

11 AM NHC kept it at 16.6N (straight west since last advisory). 

[ldub23]

JB chimes  in

 

 

[MANDA]

Have a hard time envisioning the rather sharp turn to the NW in latest TPC outlook UNLESS system becomes more vertically stacked before then.  Questionable.  I have a feeling they are going more on persistence and continuity to their prior tracks.  I think 12Z guidance is going to show some shifts and we'll see what LLC/convection looks like by this evening.  Tricky forecast on the longer range solutions for Fiona...IMO.

[Ed, snow and hurricane fan]

33 minutes ago, ldub23 said:

JB chimes  in

 

 

I'm not surprised JB is talking ECUSA and mentioning Carol.  I think all pro-mets became pro-mets because of weenie tendencies, but most pro-mets (there is someone on this board from Florida who is JB-ish) seem to feel a professional responsibility not to weenie.  He may not be wrong, but he can't help an East Coast bias.

[olafminesaw]

GFS is further south. Also, curious how that feature over Florida will end up coming into play

 

[GaWx]

MET OFFICE TROPICAL CYCLONE GUIDANCE FOR NORTH-EAST PACIFIC AND ATLANTIC

             GLOBAL MODEL DATA TIME 1200UTC 15.09.2022

        TROPICAL STORM FIONA      ANALYSED POSITION : 16.3N  53.7W

     ATCF IDENTIFIER : AL072022

                        LEAD                 CENTRAL     MAXIMUM WIND
      VERIFYING TIME    TIME   POSITION   PRESSURE (MB)  SPEED (KNOTS)
      --------------    ----   --------   -------------  -------------
    1200UTC 15.09.2022    0  16.3N  53.7W     1008            39
    0000UTC 16.09.2022   12  16.5N  56.3W     1007            40
    1200UTC 16.09.2022   24  16.7N  58.9W     1007            37
    0000UTC 17.09.2022   36  17.0N  61.4W     1006            32
    1200UTC 17.09.2022   48  17.4N  63.5W     1006            34
    0000UTC 18.09.2022   60  18.1N  65.4W     1005            36
    1200UTC 18.09.2022   72  17.8N  67.5W     1004            43
    0000UTC 19.09.2022   84  19.2N  68.9W     1001            43
    1200UTC 19.09.2022   96  19.9N  69.8W      997            56
    0000UTC 20.09.2022  108  20.7N  71.2W      994            54
    1200UTC 20.09.2022  120  21.3N  72.0W      996            51
    0000UTC 21.09.2022  132  22.0N  72.2W      993            47
    1200UTC 21.09.2022  144  23.1N  72.2W      990            48

[WxWatcher007]

17 minutes ago, olafminesaw said:

GFS is further south. Also, curious how that feature over Florida will end up coming into play

 

There’s a big kicker over the northeast. Likely well out to sea verbatim.

[MJO812]

2 minutes ago, WxWatcher007 said:

There’s a big kicker over the northeast. Likely well out to sea verbatim.

Cmc is still into the gulf

[SnoSki14]

2 minutes ago, WxWatcher007 said:

There’s a big kicker over the northeast. Likely well out to sea verbatim.

Wild to see the run to run changes a week out though. 

[TheDreamTraveler]

1 hour ago, WxWatcher007 said:

I don’t think I’d make substantive changes to intensity or track yet if I were the NHC absent recon and additional data. This one “overperformed” in terms of intensifying to 50mph, but the environment remains marginal to hostile and that is going to remain the case for at least a few days. That was never in question. 

That does make me think those quick intensification/early turn ensemble members are going to correct westward eventually. Maybe not enough to change the eventual outcome for the continental US, whatever that is, but we have a long way to go.

For sure. The adjustments west is something we've seen with so many storms in the past in this area. Would not be surprised if we see the same thing with this if it doesn't get its act together soon enough

[WxWatcher007]

4 minutes ago, SnoSki14 said:

Wild to see the run to run changes a week out though. 

The mid-level change on this run is radically different at the time frame than the prior three runs, which speaks to the volatility of the pattern itself. We’ll see what the ensembles do.

Edit: not sure if it’s truly radical, but there are significant changes verbatim in the amplitude and placement of the ridge/trough. Not a big deal in the whole scheme of things as it’s still early and we don’t have recon, but just worth discussing the model run.

[Prismshine Productions]

There’s a big kicker over the northeast. Likely well out to sea verbatim.

Yep, and Bermuda got absolutely rocked with 40+ foot waves

Sent from my SM-S102DL using Tapatalk

[Prismshine Productions]

12z GEFS supports full recurve

Sent from my SM-S102DL using Tapatalk

[MJO812]

4 minutes ago, Sandstorm94 said:

12z GEFS supports full recurve

Sent from my SM-S102DL using Tapatalk
 

It has been on that bandwagon for a while 

[Chinook]

For what it's worth, Reed Timmer has been streaming about Fiona for the last 24 minutes. I wonder what happened to Tropical Tidbits videos?

[olafminesaw]

Bye bye LLC 

[Ed, snow and hurricane fan]

1 hour ago, MJO812 said:

Cmc is still into the gulf

Canadian builds an August like ridge over it in the Gulf, but earlier on, with the weakness in the heights to the N and NE, Canadian isn't pulling this one North.  I'd think Fiona would feel that.

[Superstorm93]

30 minutes ago, Chinook said:

For what it's worth, Reed Timmer has been streaming about Fiona for the last 24 minutes. I wonder what happened to Tropical Tidbits videos?

Levi works at the JTWC now. I think he said he'll have a video out later this afternoon. 

[TheDreamTraveler]

15 minutes ago, Brian5671 said:

Of course he would mention Carol and Edna lol

[Superstorm93]

17 minutes ago, Brian5671 said:

If I had a dime for every time he's brought up that storm in the last 12 years, I'd be able to retire. 

[Superstorm93]

6z HAFS seems to be nailing the current structure 

 

 

[AChilders]

12Z euro is south of Hispaniola at 90 hours

[hawkeye_wx]

The Euro is remaining farther south this run, continuing wnw and weak over the islands.

[WxWatcher007]

Euro still runs it through Haiti/DR between 96 and 120, and then interestingly has it brushing eastern Cubs at 144. Pretty weak verbatim but may have some downstream impacts on track. 

[olafminesaw]

In the upper levels the Euro seems to have taken a step towards the Canadian with the ridging shifting east and closing the escape route. Keeps it really weak though and seems to make a broad messy system that may have a hard time organizing 

[ldub23]

All in all we still havent  had a trackable  storm this season. Its  not a tropical storm now. Maybe  its remnant will dance thru all the  islands and revive  in the  future  but  for  now  its  2022 on steroids.

 

Given its  sick appearance right  now  i would say the stronger  models may be  off just a  bit.

[AChilders]

12 minutes ago, olafminesaw said:

In the upper levels the Euro seems to have taken a step towards the Canadian with the ridging shifting east and closing the escape route. Keeps it really weak though and seems to make a broad messy system that may have a hard time organizing 

Euro does seem to trap and force it into the coastline

[olafminesaw]

The Euro is crawling. makes landfall in West Palm Beach in 9 days as a moderate TS

[floridapirate]

3 hours ago, Ed, snow and hurricane fan said:

I'm not surprised JB is talking ECUSA and mentioning Carol.  I think all pro-mets became pro-mets because of weenie tendencies, but most pro-mets (there is someone on this board from Florida who is JB-ish) seem to feel a professional responsibility not to weenie.  He may not be wrong, but he can't help an East Coast bias.

Sure, if it hits, he can take credit and if it doesnt good for everyone, something changed.  Its a win-win