ATL: IRMA - Post-Tropical - Discussion

[northjaxpro]

Msbee, great hearing from you this morning! Keep us posted as much as you are able. Praying for the best for everyone in the Islands.

[Blown Away]

http://www.nhc.noaa.gov/archive/2017/IR ... e_and_wind
Decent W shift with the cone to include more of the NE Caribbean & PR... NHC has been subtly moving that cone more SW...

[Gustywind]

nhc continues on the southerly side of guidance and that is concerning regardless of any modeling i see because nhc is extremely good on track even out to 5 days..very important for the islands, bahamas and se united states...they have held firm on the s/sw side of the equation..first up cycloneye, msbee, etc....how far south and west does it get and does it make the turn when expected, its all about the angles, rare to see intensity locked down so far out in time..until nhc changes their tune, i am looking to the left of guidance and ensembles...yikes for now

A very good post! first and foremost, our immediate concerns are the islands. I'm very concerned for our friends and neighbors down in the Northeast Caribbean . Cycloneye, gustywind and msbee in particular, I know you all are watching this situation extremely close given that Irma potentily will be bearing down on the islands later in the next 5-6 days. Keep us posted!!

Good blessed your my friend!!! ! We appreciate really those type of post ! Congrats! I can tell you that many shops have no water because of Irma possible arrival or not in Guadeloupe. So you understand that we hope that all the posters could bring some positive and pertinents informations each day. Thanks to you my friend. Regards.
Gustywind

[cycloneye]

02/1145 UTC 18.8N 42.5W T5.0/5.0 IRMA -- Atlantic

[GCANE]

Living in New York, it sends shivers down my spine to think what would happen if they had to evacuate all of Coastal Nassau County, and NYC. Any suggestions for what I should do/ buy now?

At least plywood for the windows.
You don't want to be in a long line at Home Depot later, or find out they ran out.
Can always store it somewhere.

Sump pump backup & spare batteries for it.

5-gal buckets to store fresh water.

5-gal bucket for potty and bleach to dump on it.

Canned food.

[Gustywind]

02/1145 UTC 18.8N 42.5W T5.0/5.0 IRMA -- Atlantic

Looks like more west than NHC 5 am Position... and little South.

[Blown Away]

Area Forecast Discussion
National Weather Service San Juan PR
514 AM AST Sat Sep 2 2017

.SYNOPSIS...Moisture will remain fairly rich over the area through
the next 7 to 10 days with the exception of a few narrow dry
slots that pass through. This will allow scattered to numerous
showers through the period. Hurricane Irma was located about 1500
miles east of Saint Thomas and was moving west at 15 mph. A turn
toward the west southwest is expected tomorrow. Interests in the
northeast Caribbean should monitor the progress of this system as
some impacts appear very likely.

.LONG TERM...Tuesday through Saturday...
On Tuesday the first effects of Hurricane Irma are expected as
modest lower level winds turn northeast. Weak moisture bands from
Irma are expected on Tuesday and moisture will increase over the
forecast area through Wednesday night. At this time the most
significant effect of Hurricane Irma, based on the current track
forecast by the National Hurricane Center, will be seas on the
Atlantic side of the forecast area. These will turn hazardous
beginning Tuesday even if the hurricane deviates from this track
by a significant amount. Other impacts will be primarily
determined by the track of the Hurricane, which has been
oscillating across the Atlantic east of the Virgin Islands,
according to the GFS and ECMWF, by some 400 miles. Certainly
preparations must be made for strong winds and areas of heavy
rains that could arrive as early as Wednesday. On its current
course the worst of the impacts should be over by late Thursday.
Current models leave little to no drying in the forecast, however,
and the GFS has another tropical system approaching the eastern
Caribbean on Saturday morning of next week.

** NWS PR says WSW begins tomorrow, seems to have begun already based on latest 12z 18.8N position... I edited out some of the Disco...

[GCANE]

Upper-level conditions are phenomenal.
And it'll be like that all the way to landfall.

[tolakram]

source: http://rammb.cira.colostate.edu/products/tc_realtime/storm.asp?storm_identifier=AL112017

[weathaguyry]

Living in New York, it sends shivers down my spine to think what would happen if they had to evacuate all of Coastal Nassau County, and NYC. Any suggestions for what I should do/ buy now?

At least plywood for the windows.
You don't want to be in a long line at Home Depot later, or find out they ran out.
Can always store it somewhere.

Sump pump backup & spare batteries for it.

5-gal buckets to store fresh water.

5-gal bucket for potty and bleach to dump on it.

Canned food.

Thank you for the suggestions! Much appreciated! Maybe we'll do a Home Depot run later today.

[wxman57]

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.

[GCANE]

Massive tower now spinning on the eyewall.
Spewing cirrus and layering the CDO.
Ramping up.

[Alyono]

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.

think you're giving 40 basis points too many on a recurve. I do not see a viable recurve scenario

[Blown Away]

Irma S of the forecast, maybe a wobble or trend...

[Hurricane Andrew]

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.

think you're giving 40 basis points too many on a recurve. I do not see a viable recurve scenario

Wonderful. Juuuuust wonderful.

Better start prepping a hurricane briefing for my FD, just in case.

[GCANE]

Even though there is a dry slot of low TPW to the west and south,
there is a large infeed of high CAPE air from the east.
That massive CAPE air just before the Bahamas is ominous.

[tolakram]

This was stated above, probable a good time to repeat.

We love watching models and trying to figure out where storms will go. It's all fun AS LONG AS YOU ARE PREPARED! If you're the type waiting for us, or the models, or the NHC to figure out where a storm will go YOU'RE DOING IT WRONG. Don't wait to be prepared, your only decision at this point should be if and when to execute your emergency plan.

I cringe when I see statements asking where we think it will go because someone is waiting to stock up. Get your butt to the store today if you haven't already! Many of you reading this will not be impacted by this storm, that's not the point. Be prepared, have a plan.

 https://twitter.com/Readygov/status/903962438479081472



Readygov ✔ @Readygov
Disasters Don't #PlanAhead. Make sure your family & pets have supplies ready to go in case of an evacuation. http://ready.gov/kit #Irma
8:46 AM - Sep 2, 2017

[Hypercane_Kyle]

Irma S of the forecast, maybe a wobble or trend...

Hurricanes rarely follow a straight line between two forecast points. The average position though is right on track with what the NHC is predicting.

[cycloneye]

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.

Hopefully you are right about PR but our friends in the northern Leewards could see much more right? How you see things for Guadeloupe northward

[otowntiger]

Local NWS discussion mentions strong trough at 120 hours moving through SE states and possibly affecting Irma's track. Usually 120-hour maps are fairly accurate (Harvey forecast maps were a good example, most correctly indicating 50" rainfall).

Right now we (FL) have a trough overhead, and when that pattern is in place going into September it usually persists, replaced by the subtropical high for short periods.

That could present a problem in October, but for now it always helps keep things to our east...

while it is true a trough is forcasted to be pushing in and affecting the track of Irma, (and I happen to believe it will at least to the extent Florida will be spared) however the devil is in the details. Just because a front will affect the path the critical yet to be known details are: timing, strength, tilt and other countless smaller elements in combination will make all the difference. The path could be altered from south Florida all the way to Nova Scotia.