ATL: IRMA - Post-Tropical - Discussion

[Aric Dunn]

FLorida sraights on the Euro that ridging is quite strong !

[Aric Dunn]

The eye has filled in... first ERC maybe ? its small storm .. quite possible. it was pretty concentric on that last microwave image..

[KWT]

AL, 11, 2017083118, , BEST, 0, 171N, 343W, 100, 967, HU

Irma is now a major hurricane, the second in a week

Wow, I had thought it had slowed down in intensifying but clearly not. Welcome to the major hurricane list Irma, I think your stay is going to be a long one!

Been a long time since we've had a really classic CV major, now we've got it and I think judging by the model trends, its going to be getting as much attention as Harvey got sadly. What do they say about London Buses? Don't get one for ages, then several come at the same time...

Aric, I don't expect much more strengthening from this point because as you say the eye has filled, and to be fair its pretty rare for a major hurricane this far east regardless.

[Evenstar]

Okay, I know I'm being extremely simplistic here, but I'm not a meteorologist (professional, amateur or otherwise) and need this dumbed down for me a bit. If someone lives on the GOM side, which is better news (in terms of influence), a ridge or a trough? Same question applies if someone lives (as I do) just North of OBX, which is better news, a ridge or a trough?

[Nimbus]

FLorida sraights on the Euro that ridging is quite strong !

So if you believe the Euro strong ridge scenario, then either Puerto Rico and Hispaniola have to disrupt the core of a major hurricane or its lights out in Florida.

The high resolution Euro was in the 920's close to Florida, I thought only the GFS went off like that?

Also what do you think about the ULL rolling SW ahead of Irma?

[Hammy]

First time since 2010 to have two majors in August (And the first time since 2004 to have three if Gert is upgraded post-season)

[Kingarabian]

AL, 11, 2017083118, , BEST, 0, 171N, 343W, 100, 967, HU

Irma is now a major hurricane, the second in a week

Wow, I had thought it had slowed down in intensifying but clearly not. Welcome to the major hurricane list Irma, I think your stay is going to be a long one!

Been a long time since we've had a really classic CV major, now we've got it and I think judging by the model trends, its going to be getting as much attention as Harvey got sadly. What do they say about London Buses? Don't get one for ages, then several come at the same time...

Aric, I don't expect much more strengthening from this point because as you say the eye has filled, and to be fair its pretty rare for a major hurricane this far east regardless.

Agreed, looks like just before the islands it'll begin to really bomb out.

[Aric Dunn]

FLorida sraights on the Euro that ridging is quite strong !

So if you believe the Euro strong ridge scenario, then either Puerto Rico and Hispaniola have to disrupt the core of a major hurricane or its lights out in Florida.

The high resolution Euro was in the 920's close to Florida, I thought only the GFS went off like that?

Also what do you think about the ULL rolling SW ahead of Irma?

yeah, conditions look quite good for this to stay strong pretty much anywhere it goes within the range of the models.

[SoupBone]

Can anyone explain the reason why Euro and GFS differ so much on ridges and troughs? They couldn't be more opposed at this point.

[WeatherGuesser]

When should we expect model agreement/final predictions for this storm?

Current five day cone goes to Monday/Tuesday, so I wouldn't expect much before then.

[KWT]

Can anyone explain the reason why Euro and GFS differ so much on ridges and troughs? They couldn't be more opposed at this point.

Interestingly they aren't *that* different by 192hrs, the difference comes earlier in the run as the GFs lifts up alot sooner than the ECM which keeps it deep enough that it never lifts out and sticks on a purely WNW track.

[SouthFLTropics]

Can anyone explain the reason why Euro and GFS differ so much on ridges and troughs? They couldn't be more opposed at this point.

Basically they are seeing the synoptic pattern differently. The GFS has had the low off to the NW of Irma weaken the ridge whereas the Euro hasn't really done that. The other thing is that the Euro is showing the trough over the CONUS cutting off and retrograding whereas the GFS doesn't cut it off and it erodes the western edge of the Bermuda high. Something will give at some point. Normally the answer lies somewhere in the middle.

[tolakram]

SLIDER IR

http://rammb-slider.cira.colostate.edu/?sat=goes-16&sec=full_disk&x=19852.5&y=7452.5&z=5&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

[Hurricaneman]

Looks like maybe an ewrc is starting

[Aric Dunn]

The eye has filled in... first ERC maybe ? its small storm .. quite possible. it was pretty concentric on that last microwave image..

sooo eye continues to fill in... microwave from a couple hours ago.. its a little blurry but it appears to have already started an ERC.. the outter convective band is pretty intense and quite a bit away from the very clear inner eyewall..

original image.


possible ERC.. again its a small hurricane and they can happen faster and more often than larger hurricanes and was likely a hurricane last night which means it has had time. ( sorry my inner circle is a little big so it does not cover it up just highlighting it. )

[txwatcher91]

Can anyone explain the reason why Euro and GFS differ so much on ridges and troughs? They couldn't be more opposed at this point.

Euro seems to be a bit too overpowering with ridging at times and the GFS seems to overdo a trough (or break down a ridge too fast). At this stage a good blend would be a middle ground solution, further north than the Euro but more south than the GFS shows. The 12z CMC is actually fairly close to that with a storm in the Bahamas, which seems to be the most likely solution at this point and favors climo for a storm that passes through the Herbert Box. IMO in 8-9 days we will be looking at a powerful hurricane in or near the Bahamas, and from that point where it goes will ultimately depend on the strength/position of the ridging and the location of any weaknesses.

[weathaguyry]

Jeez, 4 Hurricanes, with 2 of them Majors in one month, makes me nervous to see what the rest of the season holds

[Kingarabian]

The eye has filled in... first ERC maybe ? its small storm .. quite possible. it was pretty concentric on that last microwave image..

sooo eye continues to fill in... microwave from a couple hours ago.. its a little blurry but it appears to have already started an ERC.. the outter convective band is pretty intense and quite a bit away from the very clear inner eyewall..

original image.
[img]https://www.nrlmry.navy.mil/tcdat/tc17/ATL/11L.IRMA/gmi/color36/20170831.1626.gpm.x.color36.11LIRMA.75kts-987mb-167N-334W.55pc.jpg[img]

possible ERC.. again its a small hurricane and they can happen faster and more often than larger hurricanes and was likely a hurricane last night which means it has had time. ( sorry my inner circle is a little big so it does not cover it up just highlighting it. )

[img]https://image.ibb.co/h004Z5/20170831_1626_gpm_x_color36_11_LIRMA_75kts_987mb_167_N_334_W_55pc.jpg[img]

Man its core is so compact that it's hard to see the ERC @ 85ghz .

[p1nheadlarry]

The eye has filled in... first ERC maybe ? its small storm .. quite possible. it was pretty concentric on that last microwave image..

The wind field expands on the model runs, could possibly be ewrc

[Aric Dunn]

and sheessssh I would really like the SSD floater switched lol.. I feel like a broken record..