ATL: IRMA - Post-Tropical - Discussion

[Gustywind]

Hopefully you are right about PR but our friends in the northern Leewards could see much more right? How you see things for Guadeloupe,Antigua St Marteen,St Barts BVI and U.S Virgin Islands?

Thanks Luis, very interresting post... because of there a LOT of uncertainties with cane Irma. WE SHOULD NOT LET OUR GUARD DOWN! Too close for any comfort and to be an early recurve scenario for most of us in the Leewards

The message is dont panic but start preparations just in case Irma goes to the Islands.

Right Luis we will see.

[RL3AO]

ATCF Best Track
System ID: AL11 (IRMA)
1200 UTC Sep 02, 2017
Location: 18.9°N, 42.5°W
Central Pressure: 973 mb
Maximum Winds (1-min): 95 kt (109 mph)
Type: Category 2 Hurricane (HU)
ACE (Storm Total): 9.525

[eastcoastFL]

I'm at BJ's in Jensen Beach and the water is already disappearing. No gallons left at all and everyone here has cases of water bottles. We don't even know where the storm is going and it's already like this.

So if you think it might head your way and you aren't prepared then this weekend is probably worth the time to get a few things.

I got batteries and food and I'll be back tomorrow for gallons of water .

[msbee]

I think that Luis is going to be OK there in PR. Irma is still a relatively small storm. It's likely to pass 100-150nm north of San Juan. Far enough that TS winds will pass to the north. Could pass close enough to produce 40-50 mph sustained wind there, though.

As for the East U.S. Coast, the big question is timing. Timing of the trof/front along the east coast and Irma's arrival. A faster Irma and/or slower front/trof would mean recurve. If Irma is slower and/or the trof/front is faster, then high pressure builds north of Irma late next week, blocking recurve and shoving Irma west. I'm thinking that a US landfall is more likely than not, maybe 54% east coast landfall, 44% recurve, 2% into Gulf. I don't think that the timing is right for a Florida hit, as Irma may be north of 30N before it could be blocked. That puts SC northward under the gun.

Heading out on my bike shortly to survey the Brays Bayou flooding area. This is my first day off since weekend before last. Twelve days of 12+ hr shifts. Flooding is still bad here. Only 33" at my house. Wow! Only? Street flooding was all I saw here. However, 1/4 to 1/2 mile around me north or south and houses flooded. They're saying some homes may remain flooded for weeks on the west side.

thanks for our post wxman57. would you also feel that we will be ok here in St Maarten?
I cannot imagine how exhausted you must be. what a tragedy in Texas. Everyone's thoughts are with all of you

[otowntiger]

http://tropic.ssec.wisc.edu/real-time/mimtc/2017_11L/web/last24hrs.gif

Definitely a very small storm. This is a technical meteorological question/observation: what would occur to cause Irma to grow in size? The models seem to depict a very large system east of the US in several days. It surprises me since right now it is persistently so small and despite the many prognostications on this board about it growing after ERC, it hadn't/isn't happening. So I'm curious what factors come into play to cause s storm to grow in size? I know intensity has nothing to do with overall size- see Camille, Andrew, Charley as examples or potent small storms.

[weathaguyry]

Thank you so much for the advice, this couldn't have been more helpful!

[pgoss11]

I'm curious does a smaller storm have more energy confined to a smaller area while a larger storm's energy is spread out over a larger area? Just trying to learn about the physics behind the science. Thanks.

[Michele B]

Definitely a very small storm. This is a technical meteorological question/observation: what would occur to cause Irma to grow in size? The models seem to depict a very large system east of the US in several days. It surprises me since right now it is persistently so small and despite the many prognostications on this board about it growing after ERC, it hadn't/isn't happening. So I'm curious what factors come into play to cause s storm to grow in size? I know intensity has nothing to do with overall size- see Camille, Andrew, Charley as examples or potent small storms.

Looks like dry air keeps trying to intrude into the sw side.

That's a good thing!

[Bocadude85]

I think that Luis is going to be OK there in PR. Irma is still a relatively small storm. It's likely to pass 100-150nm north of San Juan. Far enough that TS winds will pass to the north. Could pass close enough to produce 40-50 mph sustained wind there, though.

As for the East U.S. Coast, the big question is timing. Timing of the trof/front along the east coast and Irma's arrival. A faster Irma and/or slower front/trof would mean recurve. If Irma is slower and/or the trof/front is faster, then high pressure builds north of Irma late next week, blocking recurve and shoving Irma west. I'm thinking that a US landfall is more likely than not, maybe 54% east coast landfall, 44% recurve, 2% into Gulf. I don't think that the timing is right for a Florida hit, as Irma may be north of 30N before it could be blocked. That puts SC northward under the gun.

Heading out on my bike shortly to survey the Brays Bayou flooding area. This is my first day off since weekend before last. Twelve days of 12+ hr shifts. Flooding is still bad here. Only 33" at my house. Wow! Only? Street flooding was all I saw here. However, 1/4 to 1/2 mile around me north or south and houses flooded. They're saying some homes may remain flooded for weeks on the west side.

So the odds of a Florida hit appear to be low?

[Hurricane Andrew]

:oops:

I think that Luis is going to be OK there in PR. Irma is still a relatively small storm. It's likely to pass 100-150nm north of San Juan. Far enough that TS winds will pass to the north. Could pass close enough to produce 40-50 mph sustained wind there, though.

As for the East U.S. Coast, the big question is timing. Timing of the trof/front along the east coast and Irma's arrival. A faster Irma and/or slower front/trof would mean recurve. If Irma is slower and/or the trof/front is faster, then high pressure builds north of Irma late next week, blocking recurve and shoving Irma west. I'm thinking that a US landfall is more likely than not, maybe 54% east coast landfall, 44% recurve, 2% into Gulf. I don't think that the timing is right for a Florida hit, as Irma may be north of 30N before it could be blocked. That puts SC northward under the gun.

Heading out on my bike shortly to survey the Brays Bayou flooding area. This is my first day off since weekend before last. Twelve days of 12+ hr shifts. Flooding is still bad here. Only 33" at my house. Wow! Only? Street flooding was all I saw here. However, 1/4 to 1/2 mile around me north or south and houses flooded. They're saying some homes may remain flooded for weeks on the west side.

So the odds of a Florida hit appear to be low?

Wrong. In the last 24hrs, we have seen solutions ranging from Big Bend to Bermuda.

[ace]

I think that Luis is going to be OK there in PR. Irma is still a relatively small storm. It's likely to pass 100-150nm north of San Juan. Far enough that TS winds will pass to the north. Could pass close enough to produce 40-50 mph sustained wind there, though.

As for the East U.S. Coast, the big question is timing. Timing of the trof/front along the east coast and Irma's arrival. A faster Irma and/or slower front/trof would mean recurve. If Irma is slower and/or the trof/front is faster, then high pressure builds north of Irma late next week, blocking recurve and shoving Irma west. I'm thinking that a US landfall is more likely than not, maybe 54% east coast landfall, 44% recurve, 2% into Gulf. I don't think that the timing is right for a Florida hit, as Irma may be north of 30N before it could be blocked. That puts SC northward under the gun.

Heading out on my bike shortly to survey the Brays Bayou flooding area. This is my first day off since weekend before last. Twelve days of 12+ hr shifts. Flooding is still bad here. Only 33" at my house. Wow! Only? Street flooding was all I saw here. However, 1/4 to 1/2 mile around me north or south and houses flooded. They're saying some homes may remain flooded for weeks on the west side.

Can you explain something? Why does the NHC discussions mention a subtropical high pressure that should cause Irma to move west-southwest....but the models are showing Irma turning North to the East Coast?

Asking for a friend (aka the entire Houston Metroplex).

[Bocadude85]

:oops:

I think that Luis is going to be OK there in PR. Irma is still a relatively small storm. It's likely to pass 100-150nm north of San Juan. Far enough that TS winds will pass to the north. Could pass close enough to produce 40-50 mph sustained wind there, though.

As for the East U.S. Coast, the big question is timing. Timing of the trof/front along the east coast and Irma's arrival. A faster Irma and/or slower front/trof would mean recurve. If Irma is slower and/or the trof/front is faster, then high pressure builds north of Irma late next week, blocking recurve and shoving Irma west. I'm thinking that a US landfall is more likely than not, maybe 54% east coast landfall, 44% recurve, 2% into Gulf. I don't think that the timing is right for a Florida hit, as Irma may be north of 30N before it could be blocked. That puts SC northward under the gun.

Heading out on my bike shortly to survey the Brays Bayou flooding area. This is my first day off since weekend before last. Twelve days of 12+ hr shifts. Flooding is still bad here. Only 33" at my house. Wow! Only? Street flooding was all I saw here. However, 1/4 to 1/2 mile around me north or south and houses flooded. They're saying some homes may remain flooded for weeks on the west side.

So the odds of a Florida hit appear to be low?

Wrong. In the last 24hrs, we have seen solutions ranging from Big Bend to Bermuda.

The reason I asked the question is because wxman57 said he does not think the timing is right for a Florida landfall.

[cycloneye]

@NOAA_HurrHunter
#NOAA WP-3D Orion #NOAA42 and Gulfstream IV #NOAA49 prepping for weekend flights into and around #HurricaneIrma

 https://twitter.com/NOAA_HurrHunter/status/903682418120511488

[tarheelprogrammer]

Looks like due West?

It looks to be about to take that SW dive.

[jlauderdal]

:oops:

So the odds of a Florida hit appear to be low?

Wrong. In the last 24hrs, we have seen solutions ranging from Big Bend to Bermuda.

The reason I asked the question is because wxman57 said he does not think the timing is right for a Florida landfall.

the modeling backs up wxman57 but its just a forecast and subject to change this far out, i agree with him but in now way is florida safe..small shift west and its a florida problem, i remember floyd and matthew very well, shutters up for both systems and had almost no weather from either...just up road they had power outages from matthew in palm beach county, it was that close..floyd everything in south florida was boarded up and we had a few squalls but mostly it was sunny and breezy but it was that close

[GCANE]

Concerning the energy of Irma.
Enthalpy is a good measure of the energy of a system.
COAMPS depicts this well.

Here is a comparison of Harvey at landfall and Irma forecasted at end of latest model run.

[cycloneye]

It all begins on Sunday for the squadron.P-3 NOAA plane goes on Sunday afternoon. Saturday's TCPOD.

Code: Select all

000
NOUS42 KNHC 021445
REPRPD
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1045 AM EDT SAT 02 SEPTEMBER 2017
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
         VALID 03/1100Z TO 04/1100Z SEPTEMBER 2017
         TCPOD NUMBER.....17-093

I.  ATLANTIC REQUIREMENTS
    1. HURRICANE IRMA

       FLIGHT ONE -- NOAA 42        FLIGHT TWO -- NOAA 42
       A. 03/2100Z                  A. 04/0900Z
       B. NOAA2 0111A IRMA          B. NOAA2 0211A IRMA
       C. 03/1900Z                  C. 04/0700Z
       D. 17.5N 49.0W               D. 17.2N 51.0W
       E. 03/2030Z TO 04/0030Z      E. 04/0830Z TO 04/1230Z
       F. SFC TO 10,000 FT          F. SFC TO 10,000 FT

    2. SUCCEEDING DAY OUTLOOK:
       A. BEGIN 6 HRLY FIX MISSIONS ON HURRICANE IRMA AT 04/1800Z
          NEAR 17.2N 52.5W.
       B. A G-IV SYNOPTIC SURVEILLANCE MISSION AROUND IRMA
          WITH TAKEOFF OF 04/1730Z.


[cycloneye]

It all starts on Sunday with the first mission.See the details at the Main Irma Recon Thread

[pgoss11]

Thanks GCANE. Appreciate you posting about it.

[Bocadude85]

Wrong. In the last 24hrs, we have seen solutions ranging from Big Bend to Bermuda.

The reason I asked the question is because wxman57 said he does not think the timing is right for a Florida landfall.

the modeling backs up wxman57 but its just a forecast and subject to change this far out, i agree with him but in now way is florida safe..small shift west and its a florida problem, i remember floyd and matthew very well, shutters up for both systems and had almost no weather from either...just up road they had power outages from matthew in palm beach county, it was that close..floyd everything in south florida was boarded up and we had a few squalls but mostly it was sunny and breezy but it was that close

By no means do I feel that Florida is safe, I was just curious of his opinion. If the GFS forecast of Irma hitting the mid Atlantic or Northeast Coasts 10 days out comes to fruition then I will be paying a lot more respect to the GFS from here on out.