ATL: IRMA - Post-Tropical - Discussion

[CrazyC83]

I wonder - does the NHC explicitly forecast Cat 5 intensity on the 11 pm discussion? I think yes, probably for 24 hours (could happen sooner though).

[Blinhart]

I think we will be having a strengthening Cat 5 heading for the islands for the next 48 hours, so we definitely have to look out for them. I know most of the islands are more prepared than most of the people around here are, but a Cat 5 will be bad for anyone no matter how much they prepare.

I just got to say unfortunately for Hispaniola I got to hope that Irma goes over Hispaniola and gets disrupted or it will be bad for the Bahamas, Florida Keys, and Southern Florida, even if she goes straight through the Florida Straits it have tremendous effects on all in the path of Irma.

Irma I think if goes into the Bahamas and through Key West before turning North and goes up the Spine of Florida, this will turn into a 5 Trillion dollar storm and wouldn't be surprised to hear it be the deadliest storm in history also.

[tropicwatch]

Looking like she might still have some just south of west motion left in her.

[Noles2016]

What's absolutely crazy is that 3 weeks ago, people were talking about how the Atlantic basin didn't produce classic looking hurricanes anymore...

Whoops.

[Evil Jeremy]

I wonder - does the NHC explicitly forecast Cat 5 intensity on the 11 pm discussion? I think yes, probably for 24 hours (could happen sooner though).

I would expect them to. I think she could be a Cat 5 by sunrise at this rate.

[RL3AO]

I wonder - does the NHC explicitly forecast Cat 5 intensity on the 11 pm discussion? I think yes, probably for 24 hours (could happen sooner though).

They're usually real conservative about that. I'll predict 135 kts with an explicit mention that a cat 5 is possible as it nears the NE Caribbean.

[drewschmaltz]

I think we will be having a strengthening Cat 5 heading for the islands for the next 48 hours, so we definitely have to look out for them. I know most of the islands are more prepared than most of the people around here are, but a Cat 5 will be bad for anyone no matter how much they prepare.

I just got to say unfortunately for Hispaniola I got to hope that Irma goes over Hispaniola and gets disrupted or it will be bad for the Bahamas, Florida Keys, and Southern Florida, even if she goes straight through the Florida Straits it have tremendous effects on all in the path of Irma.

Irma I think if goes into the Bahamas and through Key West before turning North and goes up the Spine of Florida, this will turn into a 5 Trillion dollar storm and wouldn't be surprised to hear it be the deadliest storm in history also.

Wow, I've been thinking some bad things myself, but this is just ... uh ... yeah. Anyway, it leads me into this: if Irma misses all large islands, I believe she will be the strongest storm to strike the continental US. Anything with a landfall pressure sub 900 takes the cake... I believe.

[Digital-TC-Chaser]

I know the western atlantic pressure field will be slightly different when the GFS takes this to the sub 900's.. but can you imagine the wind speed ? its 945 and 140 mph.. if it were to drop another 40 to 60 ++ mb ?

Aric, do you think that sub 900 mb's will verify?

no not likely.. but I was just speaking hypothetically. It could easily become a cat 5 though..

I think there should be another category for sub 900mb storms (6).

The power upgrade of the storm is unbelievable in energy released @neg-900mb.

[Patrick99]

There is still a reasonable chance this won't happen, because from this angle, a storm would really have to thread an improbable Donna-like needle up the spine of Florida.....but wow, this has a chance to be worst-case scenario from the lower Keys to Jacksonville. It's going to be a dice roll for who gets the worst of this....but I have a feeling it's going to be lower middle Keys, Marathon to Big Pine area...which would be the worst storm to hit that area since 1919.

[tatertawt24]

Urgh. This is reminding me of early morning August 28th, 2005, when Katrina finally opened up her giant eye and everyone collectively had an "Oh, ****" moment.

[CrazyC83]

000
URNT15 KNHC 050206
AF305 0611A IRMA HDOB 32 20170905
015700 1549N 05403W 6967 03158 0057 +092 +080 190044 045 039 001 00
015730 1551N 05404W 6966 03161 0057 +090 +084 187042 043 040 001 00
015800 1553N 05404W 6966 03158 0054 +093 +080 187042 042 040 000 00
015830 1555N 05404W 6965 03161 0053 +095 +065 185041 043 040 001 00
015900 1557N 05405W 6966 03157 0047 +100 +060 181040 041 042 001 00
015930 1559N 05405W 6963 03160 0044 +100 +068 179041 041 043 001 00
020000 1601N 05405W 6966 03156 0045 +100 +069 176042 042 044 001 00
020030 1604N 05405W 6966 03156 0044 +099 +067 174044 044 044 001 00
020100 1606N 05406W 6965 03156 0044 +097 +066 174045 045 046 003 00
020130 1608N 05406W 6967 03152 0043 +100 +063 173047 047 047 003 00
020200 1610N 05406W 6965 03155 0048 +093 +071 171046 047 045 003 00
020230 1612N 05407W 6967 03150 0051 +089 +080 170048 049 044 003 00
020300 1614N 05407W 6966 03152 0053 +089 +072 169049 050 044 002 00
020330 1617N 05407W 6967 03150 0051 +090 +066 167048 049 044 002 00
020400 1619N 05408W 6967 03150 0053 +087 +069 167048 049 045 002 00
020430 1621N 05408W 6964 03152 0057 +082 +076 166050 051 044 003 00
020500 1623N 05408W 6967 03149 0073 +076 //// 166051 051 043 004 01
020530 1625N 05409W 6966 03146 0069 +073 //// 162053 053 044 004 01
020600 1627N 05409W 6965 03146 0075 +072 //// 161055 056 045 005 01
020630 1630N 05409W 6967 03146 0079 +070 //// 159056 057 043 005 01
$$
;

[Blinhart]

I think we will be having a strengthening Cat 5 heading for the islands for the next 48 hours, so we definitely have to look out for them. I know most of the islands are more prepared than most of the people around here are, but a Cat 5 will be bad for anyone no matter how much they prepare.

I just got to say unfortunately for Hispaniola I got to hope that Irma goes over Hispaniola and gets disrupted or it will be bad for the Bahamas, Florida Keys, and Southern Florida, even if she goes straight through the Florida Straits it have tremendous effects on all in the path of Irma.

Irma I think if goes into the Bahamas and through Key West before turning North and goes up the Spine of Florida, this will turn into a 5 Trillion dollar storm and wouldn't be surprised to hear it be the deadliest storm in history also.

Wow, I've been thinking some bad things myself, but this is just ... uh ... yeah. Anyway, it leads me into this: if Irma misses all large islands, I believe she will be the strongest storm to strike the continental US. Anything with a landfall pressure sub 900 takes the cake... I believe.

Have you been to Miami in the past few years?? They have brand new 30 to 50 story buildings right there on Biscayne Bay and in downtown and all over. There is all types of construction going on all over Miami-Dade. Some of these new buildings I'm sure are insured for over a billion dollars, so it wouldn't take much for this to get up to a trillion just in Miami-Dade/Fort Lauderdale.

[Chris_in_Tampa]

 https://twitter.com/TropicalATL/status/904890634435223553




Radar from earlier (4:09pm to 10:44pm EDT):

https://www.youtube.com/watch?v=0-hT4F885ck

[Yellow Evan]

I think we will be having a strengthening Cat 5 heading for the islands for the next 48 hours, so we definitely have to look out for them. I know most of the islands are more prepared than most of the people around here are, but a Cat 5 will be bad for anyone no matter how much they prepare.

I just got to say unfortunately for Hispaniola I got to hope that Irma goes over Hispaniola and gets disrupted or it will be bad for the Bahamas, Florida Keys, and Southern Florida, even if she goes straight through the Florida Straits it have tremendous effects on all in the path of Irma.

Irma I think if goes into the Bahamas and through Key West before turning North and goes up the Spine of Florida, this will turn into a 5 Trillion dollar storm and wouldn't be surprised to hear it be the deadliest storm in history also.

Wow, I've been thinking some bad things myself, but this is just ... uh ... yeah. Anyway, it leads me into this: if Irma misses all large islands, I believe she will be the strongest storm to strike the continental US. Anything with a landfall pressure sub 900 takes the cake... I believe.

1935 Labor Day was 892 mbar at landfall.

[tolakram]

Keep in mind some of the models are having issues with forecasting intensity. Both the GFS and HMON have this issue. It may be a big storm, but probably cat 4, not 5. 5's are very rare, near impossible to predict, and they usually don't last very long.

SLIDER. The huge low pressure that will cause all the model issues is spinning over Canada, dropping a cold front through the Ohio valley. Impressively huge.

http://rammb-slider.cira.colostate.edu/?sat=goes-16&sec=full_disk&x=10152&y=7424&z=1&im=18&ts=1&st=0&et=0&speed=130&motion=loop&map=1&lat=0&p%5B0%5D=10&opacity%5B0%5D=1&hidden%5B0%5D=0&pause=0&slider=-1&hide_controls=0&mouse_draw=0&s=rammb-slider

[CrazyC83]

000
URNT12 KWBC 050212
VORTEX DATA MESSAGE AL112017
A. 05/01:49:08Z
B. 16 deg 40 min N
055 deg 30 min W
C. NA
D. 112 kt
E. 116 deg 12 nm
F. 211 deg 117 kt
G. 118 deg 13 nm
H. 945 mb
I. 13 C / 2449 m
J. 20 C / 2445 m
K. 15 C / NA
L. CLOSED
M. C25
N. 12345 / NA
O. 0.02 / 1 nm
P. NOAA2 0511A IRMA OB 22
MAX OUTBOUND FL WIND AND MAX FL WIND 133 KT 313 / 18 NM 01:54:01Z
MAX FL TEMP 20 C 308 / 5 NM FROM FL CNTR
CNTR DROPSONDE SFC WIND 360 / 05 KTS

[cjrciadt]

Raw T number has increased to 6.6!!

[Sanibel]

Can't wait to see what trend GFS midnight run sniffs...

[CryHavoc]

I don't use annular because it is an over used term (like the word genius) mostly by people who don't really understands what it means....but in the case...if she keeps this up for about 12 hours...I will have to say it too...amazing

Sorry, this is not an annular storm. It's not even close. Irma "keeping it up" would not meet the general requirements for an annular storm as those are not necessarily tied to any specific feature of intensity -- otherwise nearly every Atlantic hurricane that maintains intensity over warm SST would meet annular requirements. She exhibits strong rainbanding around her core and there are no mesos in her eye as of yet. Her wind field also doesn't seem to correspond to an annular storm although that is obviously in flux with her increasing in strength.

None of those are characteristic of an annular hurricane.

[CrazyC83]

000
URNT15 KNHC 050216
AF305 0611A IRMA HDOB 33 20170905
020700 1632N 05410W 6965 03149 //// +070 //// 156055 055 043 003 01
020730 1634N 05410W 6963 03150 //// +072 //// 156054 055 041 004 01
020800 1636N 05410W 6965 03149 0059 +079 +073 154052 053 042 004 00
020830 1639N 05411W 6965 03148 0059 +078 +072 151052 052 041 004 00
020900 1641N 05411W 6969 03144 0057 +080 +069 150054 054 042 004 00
020930 1643N 05411W 6963 03149 0065 +074 //// 149054 055 042 004 01
021000 1645N 05412W 6967 03146 0065 +074 //// 148054 054 041 004 01
021030 1647N 05412W 6966 03148 0059 +078 +072 145053 054 043 004 00
021100 1649N 05412W 6967 03146 0063 +078 +077 146054 054 043 004 00
021130 1652N 05412W 6968 03145 0066 +079 +079 143052 053 042 005 00
021200 1654N 05413W 6956 03160 0063 +077 +076 139055 056 042 005 00
021230 1656N 05413W 6968 03146 0059 +081 +077 140056 057 043 007 03
021300 1658N 05413W 6965 03149 0059 +081 +080 138059 061 043 005 03
021330 1700N 05414W 6971 03144 0060 +080 +078 138059 061 042 006 00
021400 1702N 05414W 6967 03148 0055 +086 +072 137057 059 040 005 00
021430 1704N 05414W 6967 03148 0053 +086 +071 138058 059 039 005 00
021500 1707N 05415W 6967 03149 0052 +089 +068 139057 057 039 005 00
021530 1709N 05415W 6967 03149 0053 +089 +065 139056 057 039 002 00
021600 1711N 05415W 6967 03150 0053 +090 +065 138058 059 040 001 00
021630 1713N 05416W 6970 03150 0052 +092 +060 134056 058 039 001 00
$$
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