ATL: FIONA - Post-Tropical - Discussion

[tolakram]

Playing with the different SLIDER views.

Day cloud phase


Red channel visible

[tolakram]

loop

[kevin]

[Jelmergraaff]

NHC has increased the sustained winds to 100 mph. Pressure down to 972 mb.

SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...20.1N 69.8W
ABOUT 130 MI...205 KM SE OF GRAND TURK ISLAND
MAXIMUM SUSTAINED WINDS...100 MPH...155 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...972 MB...28.71 INCHES

[BobHarlem]

5pm discussion late?

[cheezyWXguy]

Looking forward to what Recon finds. Fiona is rapidly improving

[kevin]

5pm discussion late?

Yep, but it's here now, forecast peak raised to 115 kt. Expected to be a MH by 18z tomorrow.

000
WTNT42 KNHC 192103
TCDAT2

Hurricane Fiona Discussion Number 22
NWS National Hurricane Center Miami FL AL072022
500 PM AST Mon Sep 19 2022

The hurricane is beginning to move away from the Dominican Republic
and over the warm waters of the Atlantic north of Hispaniola.
Fiona's cloud pattern is well organized and its inner core is
becoming better defined with very cold cloud tops becoming
concentrated near the eye. Upper-level outflow is strong over most
of the circulation. The current intensity estimate is set at 85 kt
which is a little below the latest Dvorak estimates from TAFB and
SAB. An Air Force Reserve Unit Hurricane Hunter aircraft is
scheduled to investigate the system in a few hours, and assess its
structure and intensity.

Fiona continues to move northwestward, at a slightly faster forward
speed, or at about 325/9 kt. There is little change to the track
forecast philosophy from the previous few advisory packages.
During the next couple of days, the hurricane is expected to
gradually turn toward the north while moving along the western
periphery of a mid-level subtropical anticyclone. In 3-5 days,
Fiona should turn toward the north-northeast and accelerate in
response to a vigorous mid-tropospheric trough near the northeast
coast of the United States.

Global model forecasts continue to show moderate upper-level
west-southwesterly flow over Fiona while it moves over the
southwestern Atlantic early this week. Although this flow should
cause some shear over the hurricane during the next couple of
days, the intensity guidance models indicate that this shear will
not be strong enough to prevent further intensification. The
official intensity forecast has been increased a little more for
this advisory and is in good agreement with the latest LGEM
guidance. It now appears that Fiona will become a major hurricane
sooner than previously forecast.

Near the end of the forecast period, as the system becomes more
embedded within the mid-latitude flow and interacts with the
strong mid-tropospheric trough, it should be making the transition
into a vigorous extratropical cyclone. This is also suggested by
the latest FSU cyclone phases analyses.

Key Messages:

1. Heavy rains from the trailing bands of Fiona will continue
across Puerto Rico through this evening, and across the eastern
Dominican Republic through tonight. These rains could produce
life-threatening and catastrophic flooding along with mudslides and
landslides across Puerto Rico and eastern portions of the Dominican
Republic.

2. Hurricane conditions are expected over the Turks and Caicos, with
tropical storm conditions over the southeastern Bahamas, beginning
late tonight or early Tuesday.

3. Interests in Bermuda should monitor the progress of Fiona.


FORECAST POSITIONS AND MAX WINDS

INIT 19/2100Z 20.1N 69.8W 85 KT 100 MPH
12H 20/0600Z 21.2N 70.5W 95 KT 110 MPH
24H 20/1800Z 22.8N 71.1W 100 KT 115 MPH
36H 21/0600Z 24.1N 71.3W 110 KT 125 MPH
48H 21/1800Z 25.7N 71.0W 115 KT 130 MPH
60H 22/0600Z 27.6N 70.2W 115 KT 130 MPH
72H 22/1800Z 29.9N 68.9W 110 KT 125 MPH
96H 23/1800Z 37.0N 62.3W 105 KT 120 MPH
120H 24/1800Z 48.5N 58.5W 80 KT 90 MPH

$$
Forecaster Pasch

[Iune]

Now predicting a Category 4 peak. I'm curious to see what recon finds.

[galaxy401]

If Fiona moves west enough, Nova Scotia will be in play and depending on how strong she gets they could be in for a surprise.

[InfernoFlameCat]

Bermuda may seriously get rekt. I know they are built for this, but Fiona has potential for Cat 5 status. And nothing survives Cat 5.

[aspen]

AF303 is on the pad. We’re going to have two simultaneous recon planes in Fiona tonight.

[Iceresistance]

Bermuda may seriously get rekt. I know they are built for this, but Fiona has potential for Cat 5 status. And nothing survives Cat 5.

I currently doubt that she will become a Cat 5 storm, but with how crazy she is right now, she may be able to do it. But for now, I'm giving her a very low chance that she will succeed in doing so.

[InfernoFlameCat]

Deep ring of convection now wrapping around the eye. Fiona never got disrupted in terms of structure over the DR. Yet the smallest amount of land from Puerto Rico devastates the structure to the point it lost half its eyewall.

[Iceresistance]

Deep ring of convection now wrapping around the eye. Fiona never got disrupted in terms of structure over the DR. Yet the smallest amount of land from Puerto Rico devastates the structure to the point it lost half its eyewall.

She likely bounced off higher mountains while crossing SW Puerto Rico, which may be why it may have lost parts of the eyewall before going over the Dominican Republic, which normally shreds Tropical Cyclones, but Fiona may have found an area of lower elevation over the island, which is why it never lost the structure while passing over the island.

[cheezyWXguy]

Eye temps look to be flirting with positive values on IR, it’s possible this could be approaching cat3 by the time recon gets there

[PavelGaborik10]

If Fiona moves west enough, Nova Scotia will be in play and depending on how strong she gets they could be in for a surprise.

It's a 50/50 chance at this point, and if it happened the storm would likely be significantly stronger than any potential Newfoundland strike as well.

Quite a few models take it near/into Eastern CB, which isn't overly populated.

[Zonacane]

Eye clearing out. I think Fiona may have made it to major.

[Category5Kaiju]

Bermuda may seriously get rekt. I know they are built for this, but Fiona has potential for Cat 5 status. And nothing survives Cat 5.

Hmm, not sure if it'll become that powerful as there haven't been any recorded Cat 5s at that latitude, let alone in that region of the ocean at least in historical records. But a solid Cat 4? Certainly plausible.

Also, Turks and Caicos better be prepared, as this storm is expected to come dangerously close.

[Ntxw]

Warming eye. I don't see anything in the near term to prevent this from being 120-130kts soon.

[Landy]

Fiona is wasting no time tonight. New burst on the western eyewall.