ATL: IRMA - Post-Tropical - Discussion

[tropicwatch]

Whose flying the plane? Stevie Wonder! Just kidding, probably having some instrumentation issues would be my guess.

[Blown Away]

Irma looks to pass a couple degrees N of the forecast point, could average out, but steady close to due W for past few hours...

[flamingosun]

Puerto Rico has declared a state of emergency and activated the National Guard.

[galaxy401]

Get ready everyone, this is where things are going to get very stressful for the next week. Category 4 now. Going to be a very long week. Stay prepared everyone in Irma's potential path...

[Jimsot]

Why would the storm do that in such a short period of time. Irma is addicted to EWRC'S.

Large new eyewall showing up on satellite now. Intensification likely to continue.

https://i.imgur.com/iD99pC5.gif

The dry air intrusion is over. She has crossed the mid-Atlantic, now entering warmer waters. Nothing holding her back moving forward, except for further EWRCs. Would not surprise me if we're looking at RI this evening.

luckily for the islands.. IRMA will likely be going through another ERC as it passes thorugh the islands.

[galaxy401]

Slight north shift in the new forecast cone.

[caneseddy]

New 5 PM track has Irma off he coast off Northern Cuba...just north of the 11am track...also South Florida now in the 5 day cone

[floridasun78]

miami weather man start get very worry their worry too people are thinking this not coming here not getting kit ready miami perople have bad habit getting ready last few days what weather man other channel saying????? my was from wfor met cheif

[SeaBrz_FL]

I live in brevard county about 7 miles from the coast and I see people already boarding up....

Wpec 12 Met said it is too early to put up shutters.

Although a lot of work, boarding up practice or a trial run never hurts. Usually you will find something to improve on next time.

[bob rulz]

NHC has also officially acknowledged westward motion @ 265 degrees as well. More than likely any additional southwest movement will be very slight.

[AdamFirst]

5 PM Discussion...maintains Category 4 throughout forecast period

The hurricane will be moving through an environment of low vertical
wind shear, a moist mid-level atmosphere, and increasing upper-ocean
heat content. These conditions favor intensification and the
intensity guidance continues to call for some additional
strengthening during the next couple of days. However, there are
likely to be eyewall cycles that are difficult to predict, which
could result in some fluctuations in intensity. Barring land
interaction with the islands of the Greater Antilles, Irma is
forecast to remain a powerful hurricane throughout the 5-day
forecast period.

Irma has been moving a little south of due west today, and the
longer-term motion estimate is 265/11 kt. The hurricane will
reach the southwestern portion of a strong mid-level ridge that is
centered over the central Atlantic later today or tonight. This
should result in a westward, then west-northwestward turn over the
next 24 to 36 hours. This motion is expected to bring the hurricane
near or over the northern Leeward Islands on Tuesday night or early
Wednesday. A large mid-latitude trough that is predicted to deepen
over the eastern U.S. during the next few days is forecast to lift
northeastward late in the week, which is expected to cause the
subtropical ridge over the western Atlantic to build westward.
As a result, Irma is predicted to remain on a general
west-northwestward heading on days 3 through 5. The dynamical
model guidance is in excellent agreement through 72 hours, with
some increase in spread late in the period, however the typically
more reliable ECMWF and GFS are in very good agreement through day
5, and the new NHC track forecast lies very close to those models.

Six hourly upper-air soundings began at 1800 UTC today over the
central United States to better sample the upstream mid-latitude
trough. In addition, the NOAA G-IV aircraft is currently sampling
the environment around Irma, and these data will be included in
tonight's 0000 UTC model runs.

Users are reminded to not focus on the exact forecast track since
strong winds and heavy rainfall extend well away from the center.
In addition, average NHC track errors are about 175 and 225 statute
miles at days 4 and 5, respectively.

KEY MESSAGES:

1. Irma is expected to affect the northeastern Leeward Islands a
dangerous major hurricane, accompanied by life-threatening wind,
storm surge, and rainfall impacts. Hurricane warnings are in effect
for portions of the Leeward Islands. Preparations should be rushed
to completion, as tropical-storm force winds are expected to first
arrive in the hurricane warning area by late Tuesday.

2. Irma could directly affect the British and U.S. Virgin Islands
and Puerto Rico as a dangerous major hurricane later this week.
Hurricane watches have been issued for these areas, and tropical-
storm-force winds could arrive in these areas by early Wednesday.

3. Irma could directly affect Hispaniola, the Turks and Caicos, the
Bahamas, and Cuba as a dangerous major hurricane later this week.
Residents in these areas should monitor the progress of Irma and
listen to advice given by officials.

4. There is an increasing chance of seeing some impacts from Irma in
the Florida Peninsula and the Florida Keys later this week and this
weekend. Otherwise, it is still too early to determine what direct
impacts Irma might have on the continental United States. However,
everyone in hurricane-prone areas should ensure that they have their
hurricane plan in place.


FORECAST POSITIONS AND MAX WINDS

INIT 04/2100Z 16.7N 54.4W 115 KT 130 MPH
12H 05/0600Z 16.6N 56.2W 125 KT 145 MPH
24H 05/1800Z 17.0N 58.7W 130 KT 150 MPH
36H 06/0600Z 17.8N 61.3W 130 KT 150 MPH
48H 06/1800Z 18.7N 64.1W 125 KT 145 MPH
72H 07/1800Z 20.4N 69.7W 120 KT 140 MPH
96H 08/1800Z 21.6N 74.8W 115 KT 130 MPH
120H 09/1800Z 23.0N 79.0W 115 KT 130 MPH

[Blown Away]

Lowest Latitude Predicted By Past Few NHC Forecasts:
11pm: ??? (Monday Night)
5pm: 16.6
11am:16.5
5am: 16.6
11pm: 16.5 (Sunday Night) NHC has Irma dropping father down...
5pm: 16.8
11am: 16.4
5am: 16.5
11pm: 16.5 (Saturday Night)
5pm: 16.8
11am: 17.1
5am: 17.0
11pm: 16.8 (Friday Night)

*Let's see if these subtle 6,12,18 mile adjustments N due to Irma not dropping to the predicted latitude makes a difference?

[Meteorcane]

Could you explain these plots for me please? I am quite familiar with Microwave brightness temperatures as one of my projects in grad.school was improving Tb-Rain rate algorithms associated with the TRMM satellite. Are these analogs to the Dvorak Technique (i.e. an estimator of TC intensity), but using MW instead of IR? Or are these just estimators of the exact center location using the MW imagery?

[meriland29]

She 'looks' like she is getting larger in diameter..

[jlauderdal]

miami weather man start get very worry their worry too people are thinking this not coming here not getting kit ready miami perople have bad habit getting ready last few days what weather man other channel saying????? my was from wfor met cheif

yes that is craig setzer, he is very good..setzer and john Morales on channel 6 are really the go to weather people...when they say to put shutters up then you do it..5 cases of water sitting my garage, generator ready just need 50 gallons of gas....i will be prepared for 5 days no power, no help,nothing

[Kazmit]

I hate to think of what could happen if this started rapidly intensifying. I have been to the Virgin Islands, and many of the structures are not capable of surviving Cat 4-5 winds. I'm praying for the islands now.

[GCANE]

Could you explain these plots for me please? I am quite familiar with Microwave brightness temperatures as one of my projects in grad.school was improving Tb-Rain rate algorithms associated with the TRMM satellite. Are these analogs to the Dvorak Technique (i.e. an estimator of TC intensity), but using MW instead of IR? Or are these just estimators of the exact center location using the MW imagery?

They are position estimators. Part of a suite that uses VIS and IR as well.

[johngaltfla]

I hate to think of what could happen if this started rapidly intensifying. I have been to the Virgin Islands, and many of the structures are not capable of surviving Cat 4-5 winds. I'm praying for the islands now.

Ditto. I had a wonderful time in the BVI, and I fear for those souls. Hopefully everyone is safe there as they are in my prayers. Such a wonderful area. Sigh.

[plasticup]

Whose flying the plane? Stevie Wonder! Just kidding, probably having some instrumentation issues would be my guess.

Hopefully just instrumentation

[Meteorcane]

Could you explain these plots for me please? I am quite familiar with Microwave brightness temperatures as one of my projects in grad.school was improving Tb-Rain rate algorithms associated with the TRMM satellite. Are these analogs to the Dvorak Technique (i.e. an estimator of TC intensity), but using MW instead of IR? Or are these just estimators of the exact center location using the MW imagery?

They are position estimators. Part of a suite that uses VIS and IR as well.

Thanks!