Major Hurricane Fiona

[GaWx]

 Invest 96L was just designated. Other than the precursor to Earl, this AEW to the best of my memory has had the most convection this far west in the MDR (40-45W) since the precursor to Bonnie way back in late June. The first model run with this as a TC was the UKMET way back at 12Z on September 4th though that had tropical genesis way too early (Sept 9th near 26W).

 Since then, just about every operational model has had this on some runs though it is still on and off. For example, the 6Z Euro dropped it as a TC after having it on the prior two runs. A good number of EPS and GEFS  members have shown this as a hurricane threatening the CONUS Sept 22-26, including quite a few of them landfalling in the SE, some in the Gulf, and even a few runs in the NE US including one on NYC.

 There are eight third year cold ENSO analog seasons I've been following. Among those, three of them had either the biggest or near the biggest impact of the entire season (strongest impact overall Gulf coast of FL) become a TC between 51W and 57W and during the period 9/13 and 9/20 fwiw.

 TWO odds have just increased to make this a 5 day orange from the previous lemon:

ZCZC MIATWOAT ALL
TTAA00 KNHC DDHHMM

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Tue Sep 13 2022

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

1. Central Tropical Atlantic:
Conventional and Low-earth orbit satellite data indicate that 
showers and thunderstorms associated with a tropical wave located 
about midway between the west coast of Africa and the Windward 
Islands have increased and become better organized since yesterday 
afternoon.  Further development of this system is possible and a 
tropical depression could form over the next several days while it 
generally moves westward to west-northwestward over the central 
tropical Atlantic and approaches the Leeward Islands on Friday.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 5 days...medium...40 percent.

[shaggy]

It doesn't look horrible. Hard to get angood grasp on any singular idea as the models are pretty much across the spectrum like you said from some ensemble members having a hurricane to some not developing it at all. Let's see how well it sustains during DMIN today.

[Ed, snow and hurricane fan]

GEFS aren't impressed.  Canadian and Euro ensembles are impressed.  Canadian ensembles destroy some of 96L via Hispaniola, but the ones that avoid the G. Antilles have a chance at Florida.  SHIPS is slow developing it, but GFS not seeing much LL vorticity is one of the factors affecting SHIPS.  Starting it at 15 knots also would suppress SHIPS intensity.  Puerto Rico threat per medium steering guidance used in SHIPS.

[Modfan2]

ECMWF suite appears to support recurve north; something to watch for the East Coast? Maybe discounting strength of ridge and allowing for a turn north.
 

 

[GaWx]

The 12Z ICON is a bit further south and a little weaker with it initially getting to just S of PR at 120 hours before later curving NW and then N while strengthening into a H. It ends up just E of the SE Bahamas, which is the furthest W of any run. Is this a sign that there this will keep trending SWard on later runs? I wouldn't be surprised if this ends up in the Gulf based partially on analogs fwiw.

 The 12Z GFS does ~nothing with this through 204. Its vorticity gets into the W Caribbean and may be a hint to consider.
 
 For the 2nd run in a row, the 12Z CMC has this as a TC in the Gulf with this run having it as a TS in the far E Gulf at 192. It then turns west and ends up as a H in the W GOM aiming for TX.

 The 12Z JMA, which had this as a TC the prior two days, is slightly weaker through 72 (1012 mb vs 1011 mb near the LAs). The rest of the run won't be for awhile.

 The 12Z UKMET, which has it initially only because that's how this model handles all Invests, drops this immediately afterward:

 TROPICAL DEPRESSION 96L        ANALYSED POSITION : 15.3N  46.0W

     ATCF IDENTIFIER : AL962022

                        LEAD                 CENTRAL     MAXIMUM WIND
      VERIFYING TIME    TIME   POSITION   PRESSURE (MB)  SPEED (KNOTS)
      --------------    ----   --------   -------------  -------------
    1200UTC 13.09.2022    0  15.3N  46.0W     1011            25
    0000UTC 14.09.2022   12              CEASED TRACKING

[Rhino16]

@GaWx thanks for your insane tracking on this the past couple days.

[Floydbuster]

Ugh I hate systems like this. Center reformations and not knowing if they'll end up in the Bahamas or the Gulf. 

Atleast it is something to watch.

[Normandy]

Has some definite spin and vorticity but is stretched out east to west (like every system this year)

[Ed, snow and hurricane fan]

Why aren't my 2 go to tropical satellite imagery pages not updating?

[Rhino16]

4 minutes ago, Ed, snow and hurricane fan said:

Why aren't my 2 go to tropical satellite imagery pages not updating?

“GOES data is running behind” is the message on TT.

[Windspeed]

A potential strong mid-to-upper anticyclonic wave breaking event is modeled by the 12z GFS between 72 and 144 hrs off the SECONUS that would impose shear. However, if the system can persist and position itself just north or near to the Bahamas in 5-6 days, a very favorable upper pattern may unfold for whatever potential disturbance would be in the area. There are major discrepancies between the operational GFS and ECMWF. GFS is strong with unfavorable shear out to 200 hours vs the Euro which is more favorable in the mid range. The GFS creates a mega favorable upper pattern in the 200 hrs range however. Probably would be a dangerous setup if this can make it to around Bahamas/S Florida/Cuba with an ECONUS build in heights, but that's getting into the long range, so just unknown chaos from 200+ hrs. At least something to watch.

[GaWx]

TWO remains 30%/40% but the wording seems slightly less bullish:

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Tue Sep 13 2022

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

1. Central Tropical Atlantic:
Showers and thunderstorms associated with a tropical wave located 
about 1000 miles east of the Lesser Antilles have changed little in 
organization since this morning.  Although environmental conditions 
are only marginally conducive, some gradual development of this 
system is possible over the next few days.  A tropical depression 
could form while the system moves westward to west-northwestward 
over the tropical Atlantic and approaches the Leeward Islands on 
Friday.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 5 days...medium...40 percent.

 

[shaggy]

6 minutes ago, GaWx said:

TWO remains 30%/40% but the wording seems slightly less bullish:

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Tue Sep 13 2022

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

1. Central Tropical Atlantic:
Showers and thunderstorms associated with a tropical wave located 
about 1000 miles east of the Lesser Antilles have changed little in 
organization since this morning.  Although environmental conditions 
are only marginally conducive, some gradual development of this 
system is possible over the next few days.  A tropical depression 
could form while the system moves westward to west-northwestward 
over the tropical Atlantic and approaches the Leeward Islands on 
Friday.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 5 days...medium...40 percent.

 

Hate to be in their shoes with the models having little to no consensus between them

[GaWx]

12z Euro looks to be taking a little bit further SW track based on 96 hours, when the very weak low center is 200 miles south of PR.

Edit: At 192, it is in the W Caribbean with a strong high to its north. 

Upon further review, the 12Z Euro seems to be combining 96L with some energy coming from the SW Caribbean. Anyone notice this? So, I'll need to later look at the 6 hour maps to see exactly where 96L tracked.

 And upon even more review: Check out the 12z Euro 850 mb vorticity maps. If you look closely, the NE portion of the 240 hour Bahamas low actually is associated with vorticity that is still over Africa, not the low now just offshore Africa, and won't come off til hour 48! I mean this vorticity speeds like a racehorse across the MDR! This is pretty fascinating.

 

[NorthHillsWx]

One common theme is development of this system will be a marathon, not a sprint. 

[ldub23]

2 hours ago, GaWx said:

12z Euro looks to be taking a little bit further SW track based on 96 hours, when the very weak low center is 200 miles south of PR.

Edit: At 192, it is in the W Caribbean with a strong high to its north. 

Upon further review, the 12Z Euro seems to be combining 96L with some energy coming from the SW Caribbean. Anyone notice this? So, I'll need to later look at the 6 hour maps to see exactly where 96L tracked.

 And upon even more review: Check out the 12z Euro 850 mb vorticity maps. If you look closely, the NE portion of the 240 hour Bahamas low actually is associated with vorticity that is still over Africa, not the low now just offshore Africa, and won't come off til hour 48! I mean this vorticity speeds like a racehorse across the MDR! This is pretty fascinating.

 

Which probably  means  nothing will happen. Hopefully this  is the  map in 12 days with lowering  pressure  over the  bahamas with a  large high to the  north.

 

 

I found  myself  rather disappointed  in Rick Knabb today. Just  before  3pm after the  new  Euro was  out  he was still using  last  nights  Euro to show  how  96L was going to develop off the SE  coast. He  had to know the  new Euro was totally  different. Sad to see he did  that.

[TheDreamTraveler]

Oof. That turned around quickly :/

 

[Windspeed]

Not expecting anything in the short-to-midrange. Really just need to survive as a disturbance and get better dynamics after the wave breaking event. There may be some pretty good dynamics to enhance whatever 96L is / wave near the GA or just north of it. This means a lot of boring watching until next week. I think this could be a player if it's positioned well at that time.

Specifically this setup. Any tropical surface low under that is going to intensify:


This is borderline long range however. So really how and when those upper dynamics set up is a huge ?. ECMWF is actually faster at kicking out the TUTT. So all we can do is watch how modeling evolves and if there is a disturbance in the vicinity, if that would be 96L or something behind it.

[tiger_deF]

The collapse of the convection to the left and dramatic blowup of convection tonight has made 96L look 10x better

[WxWatcher007]

Don’t really have much to add other than it looks pretty solid based on prior microwave imagery, a partial ASCAT pass, and current IR.

Agree with Windspeed and some others that we need to see this survive long enough to reach a *potentially* favorable environment. I remain skeptical but if this can persist, and that’s been a challenge all season in the tropical Atlantic, it has a shot. I think this needs to be a coherent enough disturbance to survive potential interaction with the Greater Antilles. The size may help in that regard. 

Good to see deep convection and hints of curved banding. 

[GaWx]

 Convectively, the IR satellite looks more impressive than either GFS or CMC IR simulation maps look. Also, it looks more impressive than 24 hours ago, which itself looked rather impressive, itself. Shear is pretty low and SSTs are warming as it moves westward. This is moving over a climo favored region for development in mid Sept in a non-El Nino season. Several third year cold ENSO analogs have had genesis within 51-57W between 9/13 and 9/20. Thus, I remain confident this will become a TC and it will probably become a TD before 60W. It doesn't matter much to me how the season has gone so far.

 

 That being said, the UKMET (0Z) once again does nothing with it:

TROPICAL DEPRESSION 96L        ANALYSED POSITION : 15.7N  47.3W

     ATCF IDENTIFIER : AL962022

                        LEAD                 CENTRAL     MAXIMUM WIND
      VERIFYING TIME    TIME   POSITION   PRESSURE (MB)  SPEED (KNOTS)
      --------------    ----   --------   -------------  -------------
    0000UTC 14.09.2022    0  15.7N  47.3W     1011            24
    1200UTC 14.09.2022   12              CEASED TRACKING

[Floydbuster]

Well regardless of development, the pattern favors impacts to land. I'd be surprised if this turns east of the Bahamas.

[WxWatcher007]

28 minutes ago, Floydbuster said:

Well regardless of development, the pattern favors impacts to land. I'd be surprised if this turns east of the Bahamas.

The steering pattern does look pretty ripe as long as there are no unmodeled shortwaves that erode the coming ridge. 

[Normandy]

This thing is looking well ahead of schedule

[Ed, snow and hurricane fan]

CMC still having a party, but the reliable ensembles, the weaker systems run into the G Antilles where most die, and the stronger ones recurve.  Looks decent on satellite.

[shaggy]

11 minutes ago, Ed, snow and hurricane fan said:

CMC still having a party, but the reliable ensembles, the weaker systems run into the G Antilles where most die, and the stronger ones recurve.  Looks decent on satellite.

06 GeFs is far more active with it.

[Ed, snow and hurricane fan]

Two of the more reliable globals' ensembles and the Canadian.  

 

 

 

[cptcatz]

Looking really close to a TC if not there already

[WxWatcher007]

It’s pretty close. Let’s see if it can persist through the day. 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Wed Sep 14 2022

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

Central Tropical Atlantic:
Showers and thunderstorms associated with a broad and elongated 
area of low pressure located about 800 miles east of the Lesser 
Antilles have persisted overnight and are showing signs of 
organization.  Although upper-level winds are not particularly 
conducive for additional development, only a slight increase in 
organization would result in the formation of a tropical 
depression. The system is forecast to move generally westward
over the tropical Atlantic during the next day or so, and move 
near or over portions of the Leeward Islands Friday and Friday 
night.  Regardless of development, the system is likely to bring 
gusty winds and locally heavy rainfall to portions of the Leeward 
Islands Friday through Saturday. Interests in the Leeward Islands, 
the Virgin Islands, and Puerto Rico should monitor the progress of 
this system. 
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 5 days...high...70 percent.

$$
Forecaster Brown

[WxWatcher007]

Reposting from the MA thread. 

Let's talk Invest 96L, which I highlighted as the Atlantic Lemon a week ago. 

While the guidance has waffled the last week over development odds for this one, in the last 18 hours 96L has made a sizable move toward development in advance of reaching the Lesser Antilles.

This invest has been buoyed by a large moisture envelope that to date has kept dry air from significantly disrupting convective activity. While convection did collapse yesterday, this wave has not had the look of virtually every other wave crossing the tropical Atlantic this season. 

That said, there remains reason to be skeptical. Even in the visible image above you see issues. On the NW side you can see arc clouds shooting outward, a clear sign of dry air. To the SW, you see wind shear as the cloud tops ahead get blown away. The shear analysis from this morning shows 96L threading the needle. 

I don't think this one is going to fizzle out at this point, but the above does tell me that this still has the potential to sputter as it tries to find its footing organizationally. That has implications downstream as land interaction will be key to both track and intensity. The image below is busy but important. 

This is an overlay of 00z EPS and GEFS ensemble tracks with water vapor. Once again, despite a large moisture envelope, the ever present dry air is...well...present. It wouldn't take much IMO to hold this one back, and that's basically what the guidance shows. 

There's a clear consensus, at least in this model cycle, that it remains relatively weak and heads toward the northern part of the Antilles. Places like Puerto Rico should watch this closely in case this becomes the first system of the year in the tropical Atlantic to overperform a little, which it has done so far. 

So while it has certainly made progress that may allow it to become a player in the medium to longer range, the environment is still marginal to hostile, and it has some work to do organizationally. We need to see if this organizational trend continues. If it does, that significantly increases the odds that it develops before the Antilles. 

I don't think it's really worth talking long range track right now, but this early I think all options are on the table.