ATL: DELTA - Post-Tropical - Discussion

[CrazyC83]

Lowest pressure measured was 985.3 mbar, Delta really is gonna become something special if its RI is still ahead of us. Also, since pretty much every model initialized this 15 - 20 mbar too weak, we'll have to wait for the new runs to see how this changes the forecast. When will this new data enter the models, 00z?

It may be in the early stages of RI right now. Winds right now support 55 kt.

[ElectricStorm]

Satellite looks a little ragged then before but I’m sure that’ll fix itself later tonight.

Also this plane usually has a low MSLP bias and the actual pressure is likely 3-4 mb higher then extrapolated. Real pressure is likely 988-989 mb pending dropsonde. This plane also had some issues during Isaias as well.

That's still about 10mb less than expected though...

[GCANE]

60 knt FL outbound and close to the CoC.

[Dave C]

Nice feeder band north and east of center ready to wrap in.

[GCANE]

At one point Wilma was a pinhole, 2 nm wide eye.
Just saying.

[SouthDadeFish]

The recon findings are very concerning. The inner core structure is there. Once dry air gets mixed out by ongoing precipitation and increasing BL fluxes, I suspect we will see an eruption of deep convection during diurnal maximum, when the real RI begins.

[aspen]

This pass confirms Delta has a very compact core and, like Gamma, is in a region of low background pressures. Those two combined with the exceptionally favorable conditions and high chance of RI indicate Delta is on the verge of exploding into a very intense TC that could challenge Laura as the strongest system of the year. It could continue to have a lower-than-expected pressure for its wind speeds.

[supercane4867]

At one point Wilma was a pinhole, 2 nm wide eye.
Just saying.

Current pressure readings match up with Wilma at similar intensity too. TS Wilma was ~987mb when it just strengthened to 55kt

[GCANE]

Nice feeder band north and east of center ready to wrap in.

This will probably take out the PVS

[Kingarabian]

Gonna be an interesting one to track. Hope everyone in its path is preparing.

[ElectricStorm]

Nice feeder band north and east of center ready to wrap in.

This will probably take out the PVS

The fact that Delta is already in the mid 980's even with the PVS is concerning. It's gonna get real once that PVS exits the scene.

[chaser1]

This has that look, like a tornado developing within a tropical cyclone. Small tight core + 30C = nasty strong if all else fall into place

[wxman57]

So much for my vacation and comp days this week... Delta is tracking west of south now, but should be turning NW soon. Adjusted my landfall point west to eastern Vermilion Bay mid afternoon Friday. Could be a hurricane at landfall, but I do think it will be weakening due to a combination of wind shear, dry air, and cooler water after it makes the N-NNE turn early Friday.

Hmmmm, so you're putting SE Texas in the cone now?

Beaumont is in the "cone" but that is absolutely irrelevant. The cone does not define either track uncertainty in this case or Delta's wind field. All the cone identifies is typical track error over the past 5 seasons. It never changes all season long for each storm and for each advisory. Ignore the cone! With a SW-NE jet stream along the TX coast Thu/Fri, we should be "protected". Also, Delta will be a relatively small hurricane, with hurricane force winds extending only about 20-25 miles west of the track. Finally, new guidance indicates landfall may be delayed until late Friday evening. All models do indicate significant weakening after it makes the NNE turn on Friday.

[p1nheadlarry]

This pass confirms Delta has a very compact core and, like Gamma, is in a region of low background pressures. Those two combined with the exceptionally favorable conditions and high chance of RI indicate Delta is on the verge of exploding into a very intense TC that could challenge Laura as the strongest system of the year. It could continue to have a lower-than-expected pressure for its wind speeds.

I would think intuitively that being in high background pressure would increase the radial inflow which increases the surface enthalpy fluxes since the pressure gradient is larger. Laura and Matthew are recent examples.

[EquusStorm]

[Fancy1001]

So much for my vacation and comp days this week... Delta is tracking west of south now, but should be turning NW soon. Adjusted my landfall point west to eastern Vermilion Bay mid afternoon Friday. Could be a hurricane at landfall, but I do think it will be weakening due to a combination of wind shear, dry air, and cooler water after it makes the N-NNE turn early Friday.

Hmmmm, so you're putting SE Texas in the cone now?

Beaumont is in the "cone" but that is absolutely irrelevant. The cone does not define either track uncertainty in this case or Delta's wind field. All the cone identifies is typical track error over the past 5 seasons. It never changes all season long for each storm and for each advisory. Ignore the cone! With a SW-NE jet stream along the TX coast Thu/Fri, we should be "protected". Also, Delta will be a relatively small hurricane, with hurricane force winds extending only about 20-25 miles west of the track. Finally, new guidance indicates landfall may be delayed until late Friday evening. All models do indicate significant weakening after it makes the NNE turn on Friday.

Not the GFS or parallel.

[aspen]

Already very impressive with a tiny core and expansive banding and outflow. I have a feeling Dmax will be very productive for Delta.

[catskillfire51]

interesting that most models don't have Delta breaking 990MB's until 30 hours from now.

[AutoPenalti]

Already very impressive with a tiny core and expansive banding and outflow. I have a feeling Dmax will be very productive for Delta.
https://i.imgur.com/R2Qy15x.jpg

If going by NHC's current estimates of 6 mph, it has only gone roughly 50 miles since 8am this morning... it still has a lot of time to intensify.

[wxman57]

Not the GFS or parallel.

Don't know what you're referring to.