ATL: IKE Discussion

[MiamiensisWx]

I disagree with that. A stronger storm will feel any breaks that happen to be there more than a weaker storm will. Its more into the vertical. Steering for a hurricane is all the way up to 300mb level (and I would argue a little higher)...whereas a weak TS or TD is steered by low levels.

In 4 days...there is still ridging to the north at 850...but the 300 and 500 shows it is wide open. A weak storm could move further south and west under that ridge...not a stronger one...it will get steered by the deeper flow...and that deeper flow has a break.

Its like this for every storm. Stronger storms don't go more south and west...they are steered that way by something. They don't do it because that is their nature. Their nature is to want to go to the poles. They look for any break they can find...and when you are stronger...its a lot easier to find them.

Have you also noted the fact that the Euro, UKMET, and other models have trended slower with the Midwest shortwave around day four and day five? I believe that would imply stronger residual ridging south of departing Hanna, although the Euro is clearly "overcooking" it, as evidenced by the track depicted in the 12Z run. The cutoff low in the Southwest is definitely another anomalous case where the Euro falsely indicates the presence of a deep SW CONUS cutoff low. It is possible that some models have been too fast with the shortwave over the past few days. Personally, what do you think?

[deltadog03]

Ok, so take the GFS as an outlier to the right and EURO outlier to the left...You do the math what is in the middle....

[Air Force Met]

LOL...We can't dissagree...haha I def. see your point and its the correct one. I also do believe that the GFS is breaking down that ridge too quickly. (again as you said model bias) I would like to see it hold a cyclone better though. Its prolly not significant, but just, I guess for my confidence in a model that dosn't really represent a well defined cyclone its hard to trust into it.

I would like to see it hold it better...but I am more concerned with how it does with the ridge. If the ridge is really at 27/55 with another one over the w gulf...then the break will be over FL...which means a recurve just east of there.

The other thing I notice that the GFS is doing with the ridge...that I will keep tabs on...is that it is making it N-S oriented. That would certainly argue for recurving E of Fl.

The CMC ridge is much further N and egg shaped E-W.

[Cyclenall]

I believe after breif weakening, Ike is strengthening again with a more symmetrical eye and a thin red band returning around the eye. I'd guess 120 knots right now. This is happening over 25 knots of shear? What shear? If this is what Ike is doing in these conditions, just picture non-existent shear and warmer waters ahead.

An ERC still has not occured. These types of systems that lack defined rainbands don't have them as often.

[MiamiensisWx]

I would like to see it hold it better...but I am more concerned with how it does with the ridge. If the ridge is really at 27/55 with another one over the w gulf...then the break will be over FL...which means a recurve just east of there.

The other thing I notice that the GFS is doing with the ridge...that I will keep tabs on...is that it is making it N-S oriented. That would certainly argue for recurving E of Fl.

The CMC ridge is much further N and egg shaped E-W.

That's true. The orientation of the mid/upper level ridge (as well as the amplitude/orientation of the s/w trough) is critical. It should be noted that the Euro, UKMET, and other models depict a more "elongated" (E to W) orientation of the subtropical ridge at 500 mb. As I previously mentioned, these models appear to be slower with the timing of the shortwave trough in the Midwest, as opposed to preceding runs. Your thoughts on that issue and recent trends would be interesting.

[KWT]

Cyclenall, sometimes the upper air conditions aren't very accurate to what is happening, there is some shear but it may well be in a little pocket of slightly less shear, still there thoiugh evidenced by the outflow being stronger on that SE side.

I'd go 120kts but who knows really?

miami, I noticed that as well, I think thats a key point as the models have had a habit in the past of being too quick with these features coming in and also sometimes over amplify them as well.

[Air Force Met]

AFM, i think Derek was talking about the fact the high is stronger at the upper levels, therefore the system will dive WSW more then a weak system, the BAM suite does sort of agree with that point...

a deeper system would in theory have a more amplified track i'd guess.

I would buy that better....but I personally see a more slowing down than a diving WSW. I do think it will move WSW...but due to its relationship to the high...I think it will be shorter lived than advertized (on the GFDL) and after it passes the ridge center...it will slow and resume a more westerly motion and slow down. There will probably still be some southward component...but I don't see a prolonged WSW motion. I see the latest NHC track barely has a WSW motion for a day. I think thats about right.

[cycloneye]

The 00:00 UTC BEST TRACK mantains the winds at 115kts and has a due west movement as position of 23.6n is the same as the 5 PM Advisory.

AL, 09, 2008090500, , BEST, 0, 236N, 589W, 115, 945, HU,

[canetracker]

The 00:00 UTC BEST TRACK mantains the winds at 115kts and has a due west movement as position of 23.6n is the same as the 5 PM Advisory.

AL, 09, 2008090500, , BEST, 0, 236N, 589W, 115, 945, HU, 64

Barely a Cat 4 according to that.

[Air Force Met]

Have you also noted the fact that the Euro, UKMET, and other models have trended slower with the Midwest shortwave around day four and day five? I believe that would imply stronger residual ridging south of departing Hanna, although the Euro is clearly "overcooking" it, as evidenced by the track depicted in the 12Z run. The cutoff low in the Southwest is definitely another anomalous case where the Euro falsely indicates the presence of a deep SW CONUS cutoff low. It is possible that some models have been too fast with the shortwave over the past few days. Personally, what do you think?

I did notice it. The one thing I see with the EURO is it still bolts Ike off to the W with no ridging to the north of it. I think that is fishy. The UKMET is kinda doing the same thing. There is still trofing left over from Hanna at 72 hrs and another trof coming into the midwest.

My personal attention will be forcused on the ridge and Hanna. This determines Ike's track.

[KWT]

So holding at 115kts, I suppose thats reasonable enough given the presentation hasn't really changed much.

Also yep its heading due west now, it was looking like that as the sun was setting and IR has continued that look...should start to see it drop latitude soon enough...

[MiamiensisWx]

I've also been concentrating on Hanna's forward speed and the evolution of the ridging to the southeast as well...

Personally, I believe Hanna's faster forward movement (than originally progged by the NHC) will allow the 500 mb subtropical ridge to expand west faster than your expectations. However, I also vehemently disagree with the Euro's solution, which depicts a very strong residual ridge and a movement into the Gulf of Mexico. Personally, I believe Hanna's faster forward speed and the evolving H5 set-up (as seen on CIMSS streamline analysis) will be important, especially when it is coupled with the fact that Ike has started to turn west south of the TPC forecast points.

GOES visible imagery:

http://www.ssd.noaa.gov/goes/flt/t4/loop-vis.html

CIMSS streamline analysis:

http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/wg8dlm2.html

The Floyd comparison is valid, but I personally believe the WSW turn will evolve as anticipated (in terms of duration) by the NHC; the main difference is the fact that the turn is occurring slightly earlier than progged, so Ike may be slightly farther south than the NHC's track within the medium term. That would make a difference down the road, though it largely hinges on the evolution (amplitude/speed) of Hanna's departure and the succeeding shortwave, as you and I mentioned.

Personally, it is possible that Ike could move NW or WNW through the upper Keys/southeast FL and recurve over the peninsula, though it is only one of the numerous possibilities on the table (none of which suggest a threat significantly farther west than the Florida peninsula or east of the central/eastern Bahamas). In a nutshell, I'm basically implying that it is too early to state that it will scrape or pass east of the Florida peninsula, though it is also too early to state (with 100 percent confidence) that a direct strike will take place.

[fasterdisaster]

The 00:00 UTC BEST TRACK mantains the winds at 115kts and has a due west movement as position of 23.6n is the same as the 5 PM Advisory.

AL, 09, 2008090500, , BEST, 0, 236N, 589W, 115, 945, HU, 64

Barely a Cat 4 according to that.

What? Where were you the last 4 hours?

[fasterdisaster]

Just so people are clear Ike's size will probably increase eventually from ERC(s).

[shah8]

That band of higher convection keeps trying to wrap around to the western side as of latest infrared. However, SE has a second band forming. EWRC might be beginning...

[cycloneye]

04/2345 UTC 23.6N 58.9W T6.0/6.0 IKE -- Atlantic Ocean

http://www.ssd.noaa.gov/PS/TROP/CI-chart.html

http://www.ssd.noaa.gov/PS/TROP/positions.html

[meteorologyman]

when is recon going to fly into Ike?

[cycloneye]

when is recon going to fly into Ike?

Tommorow morning NOAA plane and in the Afternoon Air Force plane.

[fasterdisaster]

That band of higher convection keeps trying to wrap around to the western side as of latest infrared. However, SE has a second band forming. EWRC might be beginning...

Yes it does look like a second eyewall may (MAY) be forming however we can't know for sure YET.

[Weatherboy1]

With Floyd, wasn't there a relatively strong cold front/trof that extended all the way down into the Gulf to steer/deflect him to the N and NE ... whereas here, the setup is more of a zonal flow/shallower trough that will eventually erode the ridge? It would seem to me that if that is the case, Ike might slow/stall rather than recurve and the turn N and NE quickly ... wether over or east of FL.