ATL: KATIA - Post Tropical - Discussion

[Ptarmigan]

Agree...it took Irene almost 2400 miles....to 60W before she got her act together...by then she was too far west to fade away without making a splash. The further east we can get these systems going, the more likely they are going to be influenced by upper-level steering troughs, and the more likely they are fish!

If it developes fairly quickly as most models suggest i'd lean towards a quick recurve. Looks like a signifcant hurricane in the making.

But several hurricanes developed well east of 50W among them Hugo and Georges to name two.

Don't forget Ike, Allen, 1900 Galveston, and 1915 Galveston. They developed well east of 50W.

[Extratropical94]

Aww, I love these plots for being so beautifully symmetric



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[wxman57]

Don't forget Ike, Allen, 1900 Galveston, and 1915 Galveston. They developed well east of 50W.

Remember Allen well, it was my first hurricane as a professional met. This is a completely different setup as far as the ridge to the north. Very strong ridging north of Allen, relatively weak for "Katia"-to-be. I believe that this storm will pass NE of the Caribbean and recurve east of the U.S. Could be a Bermuda threat, and possibly a threat to eastern Canada in a few weeks.

[cycloneye]

18z Tropical Models. Wow,SHIP is superagressive.

Code: Select all

WHXX01 KWBC 281859
CHGHUR
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS NATIONAL HURRICANE CENTER MIAMI FL
1859 UTC SUN AUG 28 2011
 
DISCLAIMER...NUMERICAL MODELS ARE SUBJECT TO LARGE ERRORS.
PLEASE REFER TO NHC OFFICIAL FORECASTS FOR TROPICAL CYCLONE
AND SUBTROPICAL CYCLONE INFORMATION.
 
ATLANTIC OBJECTIVE AIDS FOR
 
DISTURBANCE INVEST (AL922011) 20110828 1800 UTC
 
        ...00 HRS...   ...12 HRS...   ...24 HRS. ..   ...36 HRS...
        110828  1800   110829  0600   110829  1800   110830  0600
 
         LAT    LON     LAT    LON     LAT    LON     LAT    LON
BAMS    10.7N  22.8W   10.5N  25.5W   10.4N  28.3W   10.2N  31.3W
BAMD    10.7N  22.8W   10.9N  25.6W   11.2N  28.4W   11.5N  31.3W
BAMM    10.7N  22.8W   10.8N  25.5W   11.0N  28.3W   11.0N  31.0W
LBAR    10.7N  22.8W   10.8N  25.5W   11.4N  29.0W   12.2N  32.3W
SHIP        25KTS          34KTS          48KTS          61KTS
DSHP        25KTS          34KTS          48KTS          61KTS
 
        ...48 HRS...   ...72 HRS...   ...96 HRS. ..   ..120 HRS...
        110830  1800   110831  1800   110901  1800   110902  1800
 
         LAT    LON     LAT    LON     LAT    LON     LAT    LON
BAMS     9.9N  33.7W    9.4N  36.8W   10.9N  37.1W   15.7N  38.2W
BAMD    11.7N  34.0W   11.5N  38.9W   10.5N  42.6W   10.2N  44.6W
BAMM    11.1N  33.4W   10.9N  37.0W   11.5N  38.7W   14.6N  40.4W
LBAR    13.4N  35.7W   15.5N  41.7W   14.2N  46.2W   14.6N  42.8W
SHIP        73KTS          92KTS         107KTS         119KTS
DSHP        73KTS          92KTS         107KTS         119KTS
 
         ...INITIAL CONDITIONS...
LATCUR =  10.7N LONCUR =  22.8W DIRCUR = 275DEG SPDCUR =  12KT
LATM12 =  10.3N LONM12 =  20.5W DIRM12 = 273DEG SPDM12 =  11KT
LATM24 =  10.4N LONM24 =  18.2W
WNDCUR =   25KT RMAXWD =   75NM WNDM12 =   20KT
CENPRS = 1009MB OUTPRS = 1012MB OUTRAD =  180NM SDEPTH =   S
RD34NE =    0NM RD34SE =    0NM RD34SW =    0NM RD34NW =   0NM
 


[Meteorcane]

Don't forget Ike, Allen, 1900 Galveston, and 1915 Galveston. They developed well east of 50W.

Remember Allen well, it was my first hurricane as a professional met. This is a completely different setup as far as the ridge to the north. Very strong ridging north of Allen, relatively weak for "Katia"-to-be. I believe that this storm will pass NE of the Caribbean and recurve east of the U.S. Could be a Bermuda threat, and possibly a threat to eastern Canada in a few weeks.

Why is the ridging so consistently weak it seems? I thought a positive NAO is forecast? Does it have something to do with the Greenland gyre producing large numbers of shortwave disturbances?

[southerngale]

12z EURO @ 240 hours

[Florida1118]

12z EURO @ 240 hours

Hmm...Powerful Hurricane, that would be a great long tracker and ACE builder if Bermuda was going to get ruined

[painkillerr]

A good argument for this disturbance gaining latitude more quickly than the pre-Irene disturbance would be the general low pressure to its north. For Irene, the SAL was VERY strong due to a massive high to its north. Not so with this disturbance:

Wxman57, If I read you correctly, the strong SAL over Irene impeded her development until she approached 50w + or -. This is not so with 92L so development is likely to happen sooner (as it is already happenning). My question is, couldn't the high to the north impede the gain in latitude even if the SAL is not so strong?

There isn't much of a high to the north compared to when Irene was tracking west across the Atlantic. The earlier development will also significantly increase the chance of it passing north of the Caribbean and recurving out to sea well east of the U.S. The 12z Euro is in through 144 hours, indicating a path north of the eastern Caribbean with a deep trof in its path just west of Bermuda. That would give it a clear shot to recurve between 55-65W.

Thanks!

[cycloneye]

If the models are right on intensity,this will climb bigtime the North Atlantic ACE much more than what Irene did.

[BigA]

That is an epic trough that the ECMWF has toward the end of the run moving across the eastern half of the US. The 00 run didn't have it. If it exists, no way 92L gets near the US.

[BigA]

12Z GFS ensembles



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[cycloneye]

The last visible image of the day.

[cycloneye]

18z Models. Saved image.

[superfly]

Fish. Next.

[HurricaneWarning92]

Fish. Next.

its not a fish as of yet since it could affect Bermuda... plus, its days out.

[BigA]

Fish. Next.

Premature much?

This hasn't even developed. Heck, we aren't even sure it will ultimately develop at 10.5 N and not 8.5 N. And Bermuda is land.

[fci]

This thing is really far south I am skeptical of a recurve before the islands with this one.

If it gets stronger early, climatology and history say "recurve".
There are always exceptions of course, but as this point; I go with history and trends until something more definitive says to think otherwise.

[fci]

Fish. Next.

Premature much?

This hasn't even developed. Heck, we aren't even sure it will ultimately develop at 10.5 N and not 8.5 N. And Bermuda is land.

I know the term "fish" can be insensitive but many who live in the CONUS consider a storm that does not strike the CONUS to be a "fish".
I know that if a storm affects any Islands, it is technically not a "fish".

Perhaps we can invent a new, more convoluted term like "CONUS Fish"????

[CYCLONE MIKE]

Before getting to worried about the early models runs lets think back two weeks ago or so at the early model runs with Irene. Some were as far west as Houston and central gulf early on. Then started trending east, while most people thought they would eventually shift back west, they kept going east. Point is they could very well start curving more east as time goes by after some major west shifting runs.

[Extratropical94]

If this one does develop today (on August 28th), we would only be running ONE system behind 2005.
Tropical storm Lee formed on 28/8/05.
So far we have seen 10 storms (Arlene through Jose), plus one depression: TD Ten.
2005 had 11 storms (Arlene through Katrina), plus one depression: TD Ten.
Interesting similarity, right?

I know this is too early to predict, but I vote for Greek!