ATL: ZETA - Post-Tropical - Discussion

[aspen]

Zeta is starting look a bit like delta as it came in. Given that it’s pressure is still coming down a bit, it will probably peak in the next couple hours before maintaining to landfall

Zeta is basically Delta Lite — almost identical to Delta in terms of track, but not nearly as strong.

[tolakram]

recon

[Dean4Storms]

AF307 finds Extrapolated pressure of 975.7 MB

This might be good news for New Orleans as I would expect a stronger storm to move more into the Ridge to its east. Just 25 miles further east of a center track than currently forecast would be good news for New Orleans as not much wind is getting recorded by Recon on the Western side of Zeta. Now that is worse news for MS Coast and Mobile on the flip side though.

Looks like there is very little difference in the layers.

http://tropic.ssec.wisc.edu/real-time/d ... oom=&time=

Have to remember this is all shifting east and the ridge is losing ground to the Trough. Talking just 25 or so miles makes a sizable difference here for NO, that cone extends still well to the east of NO for just that possibility.

[HurricaneAndre2008]

Current Intensity Analysis



UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.0
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 28 OCT 2020 Time : 115019 UTC
Lat : 25:49:11 N Lon : 91:28:12 W


CI# /Pressure/ Vmax
5.5 / 953.4mb/102.0kt

[SconnieCane]

Current Intensity Analysis



UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.0
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 28 OCT 2020 Time : 115019 UTC
Lat : 25:49:11 N Lon : 91:28:12 W


CI# /Pressure/ Vmax
5.5 / 953.4mb/102.0kt

This shows that recon is a double edged sword (for that euro guy that's always on about how WPAC storms are underestimated because they don't have recon).

[Dean4Storms]

I certainly don't want to sound like I am down playing the threat to New Orleans but any wobbles or jogs eastward would be welcome news for those folks and a deeper storm allows that possibility in my opinion.

[Stormgodess]

Looking at the GFS, Zeta goes from New Orleans to Richmond VA in 18hrs, about as fast as you can drive it.

Saw a wind gust forecast for Alabama with it still packing 60mph gust as it leaves the Northeast corner of the state, early Thurs morning

[LowerAlabamaTider]

I certainly don't want to sound like I am down playing the threat to New Orleans but any wobbles or jogs eastward would be welcome news for those folks and a deeper storm allows that possibility in my opinion.

That would be good for them, but not so good for the Ms & Al coasts. I live about 2 miles from the west side of Mobile Bay, and right now they are saying west side of bay and rivers will have 5-8 FT surge.

[Stormgodess]

Current Intensity Analysis



UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.0
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 28 OCT 2020 Time : 115019 UTC
Lat : 25:49:11 N Lon : 91:28:12 W


CI# /Pressure/ Vmax
5.5 / 953.4mb/102.0kt

953????

[wxman57]

Current Intensity Analysis



UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.0
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 28 OCT 2020 Time : 115019 UTC
Lat : 25:49:11 N Lon : 91:28:12 W


CI# /Pressure/ Vmax
5.5 / 953.4mb/102.0kt

953????

Dvorak is far from perfect. Recon is in there. If it would only keep reporting through the next eyewall pass.

[Bamagirl2408]

I certainly don't want to sound like I am down playing the threat to New Orleans but any wobbles or jogs eastward would be welcome news for those folks and a deeper storm allows that possibility in my opinion.

That would be good for them, but not so good for the Ms & Al coasts. I live about 2 miles from the west side of Mobile Bay, and right now they are saying west side of bay and rivers will have 5-8 FT surge.


I live near Grand Bay, my son lives on the bay beside Dog River bridge. Determining if he needs to move his truck from his complex. He is 19 so of course he doesnt want to or listen.

[Iceresistance]

Current Intensity Analysis



UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.0
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 28 OCT 2020 Time : 115019 UTC
Lat : 25:49:11 N Lon : 91:28:12 W


CI# /Pressure/ Vmax
5.5 / 953.4mb/102.0kt

953????

Dvorak is far from perfect. Recon is in there. If it would only keep reporting through the next eyewall pass.

There are 2 Recon Planes inside Zeta, NOAA2 & AF307

[SconnieCane]

I'm trying not to play that whole "It's strengthening-no, it's weakening, no it's strengthening again!" frame-by-frame analysis game, but the IR satellite presentation does seem to have hiccuped recently compared to earlier this morning. It's possible Zeta is already past its narrow window to look like a classic, impressive hurricane with the onset of baroclinic interaction and rapid acceleration northward. This does not mean it cannot maintain intensity or even strengthen a little more with baroclinic enhancment*, but I do think anything above a low-end Cat. 2 is looking less likely this morning. In other words, the current NHC forecast is spot-on.

*Remember the not-so-long-ago last couple days of Epsilon?

[Dean4Storms]

I certainly don't want to sound like I am down playing the threat to New Orleans but any wobbles or jogs eastward would be welcome news for those folks and a deeper storm allows that possibility in my opinion.

That would be good for them, but not so good for the Ms & Al coasts. I live about 2 miles from the west side of Mobile Bay, and right now they are saying west side of bay and rivers will have 5-8 FT surge.


I live near Grand Bay, my son lives on the bay beside Dog River bridge. Determining if he needs to move his truck from his complex. He is 19 so of course he doesnt want to or listen.

He certainly should react to any recommendations by his local authorities and then some to evacuations and suggestions. Better safe than sorry is the rule I live by with these storms.

[GCANE]

Eye appears to be in steady state.
Running about 70% RH.

[Iceresistance]

The Eye of Zeta seems elongated to the SE.
Note that Dropsonde #18 is the NW eyewall, #19 is the eye, & #20 is the SE eyewall.

[Do_For_Love]

Zeta looking pretty tough this morning...be safe everyone.

Just to follow up on the climo discussion from earlier this week - would Zeta be the first hurricane to make landfall in the northern gulf this late in the year?

Hurricane Kate 1985 made landfall on panhandle mid-late November.

Interesting - Steve brought up Juan from '85 as well. That was a pretty active late gulf season! Hopefully this year doesn't decide to do something similar.

[Steve]

I'm trying not to play that whole "It's strengthening-no, it's weakening, no it's strengthening again!" frame-by-frame analysis game, but the IR satellite presentation does seem to have hiccuped recently compared to earlier this morning. It's possible Zeta is already past its narrow window to look like a classic, impressive hurricane with the onset of baroclinic interaction and rapid acceleration northward. This does not mean it cannot maintain intensity or even strengthen a little more with baroclinic enhancment, but I do think anything above a low-end Cat. 2 is looking less likely this morning. In other words, the current NHC forecast is spot-on.

It's hard to say. +/-7am was the likely peak per the 00z HWRF though it did drop pressure more until landfall. Currently the HRRR does as well (taking it from 979 initial at 11z down to 974 at landfall). So level but maintaining.
https://www.tropicaltidbits.com/analysi ... 2811&fh=10

[Do_For_Love]

Zeta is starting look a bit like delta as it came in. Given that it’s pressure is still coming down a bit, it will probably peak in the next couple hours before maintaining to landfall

Zeta is basically Delta Lite — almost identical to Delta in terms of track, but not nearly as strong.

Very true overall, although sadly the US landfall intensity might be about the same.

[Iceresistance]

Uh oh, NOAA2 Recon signal may have failed, no update for 30 minutes. (8:04 AM CDT)