ATL: SALLY - Post-Tropical - Discussion

[Hypercane_Kyle]

LLC likely being rocked around by that titanic burst of convection.

[bella_may]

HWRF has been right on

[xironman]

At least we have core

F. Eye Character: Open in the northwest
G. Eye Shape & Diameter: Circular with a diameter of 12 nautical miles (14 statute miles)

[cfisher]

That 993 drop is from the last pass.

[PTPatrick]

Looks like landfall around ocean springs on this advisory...and once again they phoned in the surge forecast for Jackson county, still showing 5-8 ft but have higher values west of where they have center coming in. Makes no sense. Jackson county would be in the 7-11 range if their track verifies

[GCANE]

Miss Piggy is running at 700mb - hurricane mode.

[kevin]

Pressure down to 991 mbar in the latest NHC advisory with 65 mph winds. The current NHC forecast peaks at 80 knots, up 5 knots from the previous discussion.

[Extratropical94]

991.3 mb extrapolated,

the last pass had 994.9 and the dropsonde showed 993/20 -> 991.

Smells like sub-990 to me.

[Aric Dunn]

Full on 3/4 eyewall forming...

and pressure down to 991 ish..

[hurricaneCW]

Center is still near western edge of convection. That is NOT the center in that black circle above. We have landfall near Gulfport as a 75-85 mph hurricane around 8pm tomorrow.

Concur with what others have stated. It's certainly possible the center is getting bounced around but it's clearly much closer to that convective burst. Recon has confirmed as well.

I think 75-85mph is rather conservative if the center is indeed close to the convective burst.

[kevin]

Is recon gonna make another pass?

[SouthDadeFish]

I'll be honest: the recent convective evolution over the last 3 h is deeply concerning. Radar now shows convection building into the upshear quadrants. Pressure has been dropping like a rock. These are all signs we are in the midst of an RI event. It is possible shear can disrupt the primitive inner core before it closes off, but that is seemingly less and less likely. The HWRF solution looks quite realistic right now. This system poses multiple threats (rainfall, wind, and surge).

I'm just going to re-iterate the NHC key messages below, as I cannot say them any better myself:

KEY MESSAGES:

1. It is too early to determine where Sally's center will move
onshore given the uncertainty in the timing and location of Sally's
northward turn near the central Gulf Coast. Users should not focus
on the details of the official forecast track, since NHC's average
forecast error at 48 hours is around 80 miles, and dangerous storm
surge, rainfall, and wind hazards will extend well away from the
center.

2. An extremely dangerous and life-threatening storm surge is
expected for areas outside the southeastern Louisiana Hurricane and
Storm Damage Risk Reduction System from Port Fourchon, Louisiana, to
the Alabama/Florida border, where a Storm Surge Warning is in
effect. Residents in these areas should follow any advice given by
local officials.

3. Hurricane conditions are expected tonight within the Hurricane
Warning area in southeastern Louisiana and are expected by late
Tuesday within the Hurricane Warning area along the Mississippi and
Alabama coastline. Tropical storm conditions are likely to begin
later today and this evening in these areas and preparations
should be rushed to completion.

4. Life-threatening flash flooding is likely, as well as widespread
minor to isolated major flooding, on area rivers along and just
inland of the Central Gulf Coast. Significant flash and urban
flooding, as well as widespread minor to moderate river flooding is
likely across Mississippi and Alabama through the middle of the
week. Flooding impacts are expected to spread farther across the
Southeast through the week. Sally could continue to produce flash
flooding across the Florida peninsula and prolong existing minor
river flooding across west-central Florida through today.

[FLpanhandle91]

Recon's center fix is about 15 miles northeast of the NHC 1000AM CDT position

[GCANE]

Very small, very cold-top tower now firing.
This may go sub 10nm pinhole eye.

[cfisher]

Very small, very cold-top tower now firing.
This may go sub 10nm pinhole eye.

A pinhole for now. I'd expect it to widen given the warming tops near convection further south

[Aric Dunn]

Recon's center fix is about 15 miles northeast of the NHC 1000AM CDT position

They should.

but there is also another plane that just took off.

[3090]

Still too close for comfort for the eastern side of lower Louisiana coast for first landfall. We'll see. It could miss the entire eastern side of the Louisiana coast altogether.

[tropicwatch]

Recon's center fix is about 15 miles northeast of the NHC 1000AM CDT position

They should.

but there is also another plane that just took off.

Hope this is still the center getting its act together and not actual movement.

[MGC]

With the reformation of the center to the NE and into the deep convection I think the chances of Sally becoming a hurricane now are near 100%. Sally's 5KTS forward speed is either due to center reformation or the storm is nearing where it will start to recurve. Sally is looking better on sat loop....might be getting ready to take off......MGC

[cheezyWXguy]

Very small, very cold-top tower now firing.
This may go sub 10nm pinhole eye.

Think you're right. There is a very small core forming on radar now.