ATL: HERMINE - Post-Tropical - Discussion

[CrazyC83]

000
URNT15 KWBC 291812
NOAA3 0709A CYCLONE HDOB 08 20160829
180230 2452N 08600W 8359 01661 0103 +186 +156 064017 018 022 000 03
180300 2451N 08601W 8529 01484 0103 +194 +166 062018 018 /// /// 03
180330 2451N 08603W 8903 01111 0103 +210 +183 070019 019 015 003 03
180400 2452N 08606W 9127 00897 0105 +221 +197 075020 020 024 000 00
180430 2453N 08607W 9187 00841 0107 +226 +199 074020 020 023 000 03
180500 2455N 08608W 9212 00817 0109 +227 +208 075019 020 023 000 03
180530 2456N 08606W 9216 00811 0109 +226 +210 076019 019 019 000 03
180600 2455N 08605W 9225 00807 0107 +226 +207 077019 019 022 000 00
180630 2454N 08603W 9218 00809 0106 +226 +208 077020 020 022 000 03
180700 2453N 08602W 9216 00811 0102 +230 +201 077020 021 021 000 00
180730 2452N 08600W 9217 00808 0101 +229 +199 076020 020 020 000 00
180800 2451N 08559W 9217 00808 0100 +230 +198 076020 020 020 000 00
180830 2450N 08557W 9217 00808 0100 +231 +200 075020 020 022 000 00
180900 2448N 08556W 9216 00808 0100 +227 +205 076020 020 022 000 00
180930 2447N 08554W 9219 00806 0100 +227 +204 074020 020 019 000 00
181000 2446N 08553W 9221 00805 0100 +227 +207 071021 021 020 000 00
181030 2445N 08551W 9219 00805 0099 +228 +208 069020 022 021 000 00
181100 2443N 08550W 9218 00805 0098 +231 +210 065019 019 022 000 00
181130 2442N 08549W 9216 00806 0097 +231 +210 058020 021 024 000 00
181200 2441N 08547W 9219 00805 0098 +232 +204 062018 020 024 000 00

[Aric Dunn]

Your statement about the poor initialization made me curious so I took a look at the 12Z initialization. I'm looking at a high-res plot of the 12Z EC & GFS, with pressure plotted at 1/2 mb increments (I can plot pressure down to 0.1mb increments). The 12Z GFS initialized the center at 23.08N / 84.95W. The EC had it at 23.62N / 84.76W. The Euro is a bit closer than the GFS, which is too far south. Both initialized it pretty well, I think.

well I dont have the higher resolution .. the GFS is quite a bit farther west than where it is now..maybe your better resolution fixes the issue idk..

but most of the models were off a little to well quite a bit like the gfs.

https://s17.postimg.io/mzne2ixlr/gfs_ms ... 09_L_1.png

That automated chart on Levi's page has the low in the wrong place. If you look at the surface low with the 10m winds plotted then you can see the low is well east of where it was placed on his map.

ok with the 10m wind the GFS is not in the yucatan channel but near the Euro which is still about 75 miles off but maybe your resolution is different.

[Airboy]

This "must" be a TS now, would be suprised if it's not.

[chaser1]

Hello everyone. Long time lurker, first time poster from SE LA. I do have a question. Since most computer models already have TD9 on a wnw to nw track, how will it's current wsw movement affect the result? We all remember what wsw did to Katrina.

Welcome! Well, its pretty hard to say right now. Firstly, until there is a well identified center of circulaton then the recent (or current) motion is speculative. Of course getting recon into the system shortly will definately help clear up a couple of things. "Where" is there an alligned low/mid level center (presumably under the present bursting convection) and what is its actual motion and speed of motion. Very generally one could assume that the further west this goes, than potentially the further west any point of landfall could also be too. Bottom line is that weaker systems move with a lower flow of air while stronger storms tend to be moved by a mid-level flow. Furthermore, how deep or strong of a T.D. or T.S. that we might have also plays a larger role in how well the various models are able to predict motion and eventual intensity. This is largely why so many have been pulling their hair out trying to figure what will actually occur and why the models thus far have been up and down. So... what does near term WSW mean? I don't think it means all that much until we at least know if we finally have a somewhat deep core tropical system. Stay tuned

[Aric Dunn]

This "must" be a TS now, would be suprised if it's not.

recon. pressure 1009 well away from the center

[DucaCane]

Thanks for your reply StormHunter72. Still keeping my guard up until it makes that easterly move.

[toad strangler]

Agreement as far as landfall location goes between 12z ECMWF and 12z GFS
Right in the ARMPIT of FL

[chaser1]

This "must" be a TS now, would be suprised if it's not.

recon. pressure 1009 well away from the center

hmmmmm; well i'd guess it should be at least down to 1005mb, otherwise we're not talking about too tight of a gradient and perhaps evidence that it hasnt strengthen too much. By appearance though, i'd have to think thats not the case. I'm feeling 1003mb

[CrazyC83]

000
URNT15 KWBC 291822
NOAA3 0709A CYCLONE HDOB 09 20160829
181230 2439N 08546W 9221 00802 0098 +231 +205 061021 021 022 000 00
181300 2438N 08544W 9220 00803 0098 +228 +208 062021 021 022 000 00
181330 2437N 08543W 9219 00803 0097 +230 +202 061020 021 022 000 00
181400 2436N 08541W 9218 00803 0097 +226 +198 069020 020 024 000 00
181430 2435N 08540W 9218 00803 0097 +225 +200 070019 019 022 000 00
181500 2433N 08538W 9221 00800 0098 +229 +198 067019 019 022 000 00
181530 2432N 08537W 9220 00800 0096 +228 +202 068020 020 022 000 00
181600 2431N 08535W 9221 00800 0095 +228 +205 070020 021 021 000 00
181630 2430N 08534W 9222 00799 0096 +227 +206 071020 020 021 001 00
181700 2428N 08532W 9216 00803 0097 +226 +204 072021 022 021 001 03
181730 2427N 08532W 9220 00800 0098 +225 +209 068021 022 021 000 00
181800 2425N 08532W 9222 00798 0097 +225 +205 069021 021 021 000 00
181830 2423N 08531W 9223 00798 0096 +225 +207 068021 021 020 000 00
181900 2421N 08531W 9223 00797 0096 +225 +212 064020 021 020 000 00
181930 2419N 08531W 9225 00795 0094 +227 +215 065020 020 021 000 00
182000 2417N 08530W 9225 00794 0094 +226 +216 063019 020 020 000 00
182030 2416N 08530W 9225 00794 0093 +227 +217 064018 019 022 000 00
182100 2414N 08529W 9225 00795 0093 +228 +209 062019 020 020 000 00
182130 2412N 08528W 9223 00795 0093 +230 +200 061018 018 017 000 00
182200 2410N 08527W 9225 00793 0092 +230 +200 059016 016 018 000 00

[hurrtracker79]

 https://twitter.com/hurrtrackerapp/status/770323407267323904

[Hurricane Andrew]

This "must" be a TS now, would be suprised if it's not.

recon. pressure 1009 well away from the center

hmmmmm; well i'd guess it should be at least down to 1005mb, otherwise we're not talking about too tight of a gradient and perhaps evidence that it hasnt strengthen too much. By appearance though, i'd have to think thats not the case. I'm feeling 1003mb

Imma go with 1004 for the first vortex message, and 1000 for the last.

[wxman57]

also clearly from the resolution i have.. even the Euro is about 75 miles to far to the NW initially..

http://www.tropicaltidbits.com/analysis ... seus_1.png

Have to be careful with that low-res data. I measure the 12Z EC to be about 27nm west of the 12Z position. The center actually jumps east to be over the 15Z position at the 3-hr forecast point. Pretty darn close.

[GCANE]

The outflow is actually inducing shear all an axis running east / west around 25 to 26N
Low and mid-level winds are out of the east.
Upper level winds out of the south from the outflow.
Small convection firing off from the shear.
Will help with the mid-level dry air intrusion.

[benh316]

recon. pressure 1009 well away from the center

hmmmmm; well i'd guess it should be at least down to 1005mb, otherwise we're not talking about too tight of a gradient and perhaps evidence that it hasnt strengthen too much. By appearance though, i'd have to think thats not the case. I'm feeling 1003mb

Imma go with 1004 for the first vortex message, and 1000 for the last.

If we are playing Price is Right rules - I will go with 1001mb Bob

[DucaCane]

Hello everyone. Long time lurker, first time poster from SE LA. I do have a question. Since most computer models already have TD9 on a wnw to nw track, how will it's current wsw movement affect the result? We all remember what wsw did to Katrina.

Welcome! Well, its pretty hard to say right now. Firstly, until there is a well identified center of circulaton then the recent (or current) motion is speculative. Of course getting recon into the system shortly will definately help clear up a couple of things. "Where" is there an alligned low/mid level center (presumably under the present bursting convection) and what is its actual motion and speed of motion. Very generally one could assume that the further west this goes, than potentially the further west any point of landfall could also be too. Bottom line is that weaker systems move with a lower flow of air while stronger storms tend to be moved by a mid-level flow. Furthermore, how deep or strong of a T.D. or T.S. that we might have also plays a larger role in how well the various models are able to predict motion and eventual intensity. This is largely why so many have been pulling their hair out trying to figure what will actually occur and why the models thus far have been up and down. So... what does near term WSW mean? I don't think it means all that much until we at least know if we finally have a somewhat deep core tropical system. Stay tuned

Thank you for the explanation. I'll definitely be watching. Up until now this has been extremely entertaining. Still entertaining, although it's getting real for those of us along the Gulf coast.

[chaser1]

recon. pressure 1009 well away from the center

hmmmmm; well i'd guess it should be at least down to 1005mb, otherwise we're not talking about too tight of a gradient and perhaps evidence that it hasnt strengthen too much. By appearance though, i'd have to think thats not the case. I'm feeling 1003mb

Imma go with 1004 for the first vortex message, and 1000 for the last.

If you're right, than i'll be REALLY curious to see how the 0Z models begin to handle future intensity.

[Aric Dunn]

also clearly from the resolution i have.. even the Euro is about 75 miles to far to the NW initially..

http://www.tropicaltidbits.com/analysis ... seus_1.png

Have to be careful with that low-res data. I measure the 12Z EC to be about 27nm west of the 12Z position. The center actually jumps east to be over the 15Z position at the 3-hr forecast point. Pretty darn close.

I try with what I have

[chargurl]

Are there areas south over land, that recon can't fly, and if not, doesn't that effect the model input?

[Hurricane Andrew]

hmmmmm; well i'd guess it should be at least down to 1005mb, otherwise we're not talking about too tight of a gradient and perhaps evidence that it hasnt strengthen too much. By appearance though, i'd have to think thats not the case. I'm feeling 1003mb

Imma go with 1004 for the first vortex message, and 1000 for the last.

If you're right, than i'll be REALLY curious to see how the 0Z models begin to handle future intensity.

FWIW, HRRR has this system down to 998 by 18 hours, tracking mostly WNW. Now. HRRR accuracy is somewhat...uncertain at 18 hrs, but it is food for thought.

[chargurl]

I mean to add, south of depression, over Cuba?