ATL: IRMA - Post-Tropical - Discussion

[Blinhart]

How far N will the NHC need to shift that 5 day point? Upper Keys my guess.

I don't think the cone will move that much at all since she is still on a slightly south of west movement still.

[Sciencerocks]

noaa

005030 1521N 05614W 7504 02541 0043 +146 +093 302035 036 024 001 00
005100 1521N 05611W 7499 02544 0042 +145 +092 300036 036 023 002 00
005130 1521N 05609W 7501 02541 0042 +143 +091 298036 036 022 002 00
005200 1521N 05607W 7500 02541 0040 +144 +091 299036 037 023 002 00
005230 1521N 05604W 7502 02538 0040 +145 +091 299036 036 022 002 00
005300 1521N 05602W 7500 02537 0037 +145 +092 297037 038 026 001 00
005330 1521N 05559W 7499 02538 0036 +146 +088 294038 038 025 002 00
005400 1521N 05557W 7498 02539 0034 +147 +090 292038 038 026 001 00
005430 1521N 05555W 7500 02535 0034 +145 +093 290039 040 027 001 00
005500 1521N 05552W 7499 02533 0036 +141 +097 285037 038 027 001 00
005530 1521N 05550W 7504 02530 0038 +139 +101 284038 039 026 001 00
005600 1521N 05547W 7499 02532 0035 +139 +109 281037 038 028 001 00
005630 1521N 05545W 7497 02536 0035 +140 +093 282038 039 028 001 00
005700 1521N 05542W 7500 02530 0037 +136 +100 279037 038 028 001 00
005730 1522N 05540W 7501 02528 0038 +136 +104 275038 038 027 001 00
005800 1522N 05538W 7498 02532 0035 +137 +101 273039 040 027 002 00
005830 1522N 05535W 7499 02528 0033 +138 +096 270038 038 029 001 00
005900 1522N 05533W 7500 02528 0033 +137 +103 268037 038 027 001 00

[Aric Dunn]

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 ?

[SootyTern]

Here is a great site for predicting storm surge potential. You can zoom in to s FL and then choose your storm category from 1-5. http://noaa.maps.arcgis.com/apps/MapSer ... ad&entry=1

That surge will be epic if GFS verifies. Everything East of US 1 up to Cutler is under water in that scenario. Evacs are going to be massive and unprecedented. Better book now folks! Tallahassee is my refuge and I booked it last night waiting on the Euro.

I visited the NHC on a public tour they had the first year I moved down here (2000) and asked them what would keep a storm surge from crossing from the Atlantic to the Gulf at our latitude (I'm in Homestead/Florida City, due east of Turkey Point). The answer was that theoretically it was possible if a dome of surge lasted long enough, but usually surge events move fast enough that friction over land slows down the progress of seawater inland. I'm about 5 miles inland; way more concerned with rainfall flooding and wind damage than saltwater surge.

[SFLcane]

 https://twitter.com/MJVentrice/status/904869577712132096

[Aric Dunn]

latest image is in..

deepening.. .. very classic hurricane. now if that convection can deepen and the tops cool some more. then we will have a CAT 5..

[Ntxw]

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 ?

She's not that small as it is now so as she drops pressure her wind field will expand rather than precipitous rise in winds. The storms that pack crazy winds with the sub 900s (not all) tends to be tightly packed cores. If this thing were about to really tank in the upper echelon of pressures with wind we'd probably get an idea if BD starts showing ring of Grey with a small eye and wicked pressure gradient

[Sciencerocks]

000
URNT15 KNHC 050106
AF305 0611A IRMA HDOB 26 20170905
005700 1718N 05556W 6963 03094 9994 +096 +096 062070 073 048 014 00
005730 1717N 05555W 6968 03086 9974 +094 +079 056071 073 048 015 03
005800 1716N 05553W 6966 03087 9975 +093 +072 048072 073 052 015 03
005830 1715N 05552W 6967 03082 9975 +089 +076 044071 071 054 011 03
005900 1714N 05551W 6962 03084 9973 +087 +078 041074 076 055 007 00
005930 1712N 05550W 6969 03071 9962 +092 +072 040080 081 058 007 00
010000 1711N 05548W 6967 03070 9967 +083 +074 040083 084 057 011 00
010030 1710N 05547W 6967 03059 9969 +080 +080 044082 087 059 014 03
010100 1709N 05546W 6970 03047 9968 +081 +081 050079 082 066 008 00
010130 1708N 05545W 6971 03039 9946 +086 +086 054085 086 071 005 00
010200 1707N 05544W 6964 03037 9917 +091 +089 053094 097 072 005 00
010230 1705N 05543W 6966 03025 9909 +090 +087 052091 095 074 007 00
010300 1704N 05541W 6970 03010 9879 +103 +087 050087 089 075 004 00
010330 1703N 05540W 6974 02993 9866 +103 +087 051093 096 077 004 00
010400 1702N 05539W 6970 02985 9854 +100 +087 054096 100 078 011 00
010430 1701N 05538W 6959 02979 9843 +093 +090 055101 103 079 012 00
010500 1700N 05537W 6969 02951 9831 +092 +092 056109 111 082 016 00
010530 1659N 05536W 6974 02930 9809 +097 +097 056105 109 091 008 00
010600 1658N 05535W 6966 02919 9774 +103 //// 055111 112 094 004 01
010630 1657N 05534W 6962 02904 9759 +107 //// 054116 118 099 005 01
$$
;

[eastcoastFL]

Too get an idea as to how warm the waters are around Florida and in that vicinity. 30°C equates to 86°F.

That can't be right 86 degrees? I was in key largo last weekend and the water didn't feel that warm. But I'm sure the maps are pretty close. Crazy.

[Aric Dunn]

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 ?

She's not that small as it is now so as she drops pressure her wind field will expand rather than precipitous rise in winds. The storms that pack crazy winds with the sub 900s (not all) tends to be tightly packed cores. If this thing were about to really tank in the upper echelon of pressures we'd probably get an idea if BD starts showing ring of Grey

true but there are always exceptions ( many ) .. we are also talking about 40 to 60 plus mb.. size wont matter with that type of pressure change.

[Blown Away]

Looks like just N of the next forecast point, could drop down before, but due W seems to be the course...

[tropicwatch]

Just becoming incredible.

[seaswing]

New trend in the models is a tad bit more North of the islands which is great for them. Of course, that just means even more time for Irma to tap into those hot waters before that *likely* turn into S.Fla.

Is Thursday or Friday too late for evacuations from Miami-Dade if this approaches starting Saturday into Sunday?

Rely on local authorities, but just my two cents: No, not too late at all, if a hit on Miami is forecast, and you are in an unsafe structure, plan on going somewhere at any time, even a few hours before TS winds arrive. Traffic, gas supplies and hotels will be a problem. If you can leave late at night or very early morning you might avoid traffic. Plan to not go any farther than necessary to get out of surge/flood zone and into sturdy shelter. FIU is one choice, although it may fill up from Keys residents. For Andrew I took US 27 up to Highlands county to avoid the interstates, but people were having to go to Orlando or farther to find hotel rooms. In Wilma the turnpike was a nightmare for evacuation. If the current track holds, Miami will not get the full force, and you may be OK unless in a mobile home or low-lying area.

Not sure any part of Florida is completely safe at this point because inland will have a lot of rain and depending on the category, we are constantly under tornado watches and warnings. But for Andrew, people came to Gainesville and did fine. We opened school auditoriums, etc. I worked at Santa Fe College and the gym was full of people.

[eastcoastFL]

Windfield appears quite a bit larger than NHC's last advisory.

ESTIMATED MINIMUM CENTRAL PRESSURE 944 MB
EYE DIAMETER 15 NM
MAX SUSTAINED WINDS 115 KT WITH GUSTS TO 140 KT.
64 KT....... 35NE 30SE 20SW 30NW.

Recon shows 70 to 80 kt FL winds up to 80 nm from the center in the NE and NW quadrants.

Why do they still show 40miles for hurricane and 140 for TS winds?

[RL3AO]

Windfield appears quite a bit larger than NHC's last advisory.

ESTIMATED MINIMUM CENTRAL PRESSURE 944 MB
EYE DIAMETER 15 NM
MAX SUSTAINED WINDS 115 KT WITH GUSTS TO 140 KT.
64 KT....... 35NE 30SE 20SW 30NW.

Recon shows 70 to 80 kt FL winds up to 80 nm from the center in the NE and NW quadrants.

Why do they still show 40miles for hurricane and 140 for TS winds?

It's from the 5 pm advisory

[Cuda]

In terms of damage, if a cat 5 were to make landfall and travel directly up the spine, how much damage would be done (how much intensity would be lost) when it got to an area like Orlando or Tampa. Would we still be looking at Cat 3 winds that could potentially damage buildings etc?

[Prof]

I'm getting really stressed about figuring out where to go. Will the roads be too crazy to drive on Thursday?

[AFWeather]

Do the Hurricane Hunters have a secondary Caribbean location to fly out of if (when) St. Croix can't be flown out of.

Barbados I would think

Just spoke with my Hurricane Hunter buddy... they fly the mission out of St. Croix tomorrow morning, and will recover at Curacao upon completion.

[GeneratorPower]

I'm getting really stressed about figuring out where to go. Will the roads be too crazy to drive on Thursday?

You need to put your location in your profile.

[RL3AO]

130 kt FL/117 kt SFMR in NW eyewall which is the strongest so far.