Large Scale Synoptics Impacting Where 99L Goes in the Long-t

[gatorcane]

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

I wouldn't mind having a thread for this as the other thread has been inundated on many comments regarding the situation now with 99L - but the key question is what will be the situation later and steering currents for this thing.

Right now it is embedded within a strong East to West flow which should keep it moving West for the next several days. It should slow some as it moves into the Eastern Caribbean. Down the road, I'm just not seeing the big ridging some people are talking about that should take this into Mexico or Belize. All of the models I just checked, the GFS, CMC, and NGPS ALL show weaknesses in the western periphery of the ridge at 96+ hours. That would keep 99L moving along a general West to WNW course until reaching the NW Caribbean or just before the NW Caribbean at that point it would be able to take a more NW or N movement -- (does this not remind you of 2004??)

I'm starting to wonder if a Dennis-like, Ivan-like, or even Charley-like track is in store here (whether 99L gets that strong is not the question here). I'm leaning less at the Charley-like track but we are near the time of year that Charley got scooped up by an unusual short-wave. Climatology would also argue against a low runner into Mexico for this time of year.

Some other wild cards to note. The CMC develops a low in the Northern GOM and there could also be a low forming off the SE Coast of the US. Both features could make this forecast very tricky should they develop any.

I would like to see any other thoughts on the global synoptics that could impact where 99L goes would

[gatorcane]

Let's bump this thread - as our invest did have a "down" day yesterday we should start talking about where this thing is going to go......

All of the models are showing a building ridge for the next 3-4 days followed by a weakening of the western periphery. This will allow a path into the NW Caribbean.

http://moe.met.fsu.edu/tcgengifs/

Also the TUTT low off to the west may help push it WNW some but this won't happen for at least 2-3 days once our system gets closer to the low.

If the system deepens further I would expect it to gain some more lattitude...

[Jam151]

That was then....this is now. This is no 2004, 2005, or 2006. Coming up on the date of Charley does not = recurvature into Florida either.

/thread

[SouthFloridawx]

Well, I think 99L will swiftly move off to the west into C. America.

[Stormcenter]

I don't see this entering the GOM right now.

[Sanibel]

Good topic gatorcane.

If you look at the "NW Atlantic" WV loop you can see a weakening stationary trough over the east coast that becomes W-E oriented over the east Gulf of Mexico. Go further down over southern Yucatan and you can see strong wisps shooting over towards EPAC across Central America. Since the CONUS trough isn't plunging we can assume a cyclone will do what most cyclones do and ride the periphery of whatever guiding ridge there is down there into recurve somewhere in the Gulf area. I think this will develop like other fast-moving systems we have seen 'skip' through the eastern caribbean before forming in the western caribbean. This is important because of its potential - even though it could still be early and intensity may be limited still.

So, if we assume a hurricane I would watch for recurve into the Gulf. If you go to Puerto Rican long range radar you can see some thin outer bands suggesting a NW movement. This could just be the natural expansion of rotating bands - or it could be a WNW component. Not sure. In any case, the stationary trough is significant enough that it should exert some 'pull' on the system if it develops. So it would be normal to assume a compromise between the apparent westward guidance in the caribbean and the east coast trough - IF - a ridge doesn't wedge in on top of it and steer it straight west and into Belize. But a quick view of the WV loop doesn't suggest this. There's no real Bermuda High showing itself at the moment.

If it does form I think it will go west of Florida.

[Ed Mahmoud]

I'm not a meteorologist, nor do I play one on TV


Looking at all the models that at least track an 850 mb vort, I'd say this does not get classified today, but if they fly late enough tomorrow when it gets a little farter from South America, it will become Dean, and late Sunday/early Monday be a Cat 1 or Cat 2, outside shot Cat 3 due high Heat Content, somewhere near Bluefields, NI

[Sanibel]

I'm having trouble judging if there is a wedge of High in front of it or not. If there is then Mahommed's prediction could be correct. But it doesn't look like it on WV.

[skysummit]

I argree Sanibel. I'm having a harder and harder time agreeing with the westward run considering this mess in the Gulf.

[DESTRUCTION5]

Well, I think 99L will swiftly move off to the west into C. America.

Agree..Iris type track...

[SouthFloridawx]

I say that a track into the Southern Yuch. as Derek pointed out before is most prudent.

I don't think she'll slow down too much either.

Scotty, slow the engines down... she doesn't need anymore forward speed.

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/carib/gfs/18/images/gfs_500_048l.gif

[Brent]

Well, I think 99L will swiftly move off to the west into C. America.

Agreed.

There is a ridge up here and no fronts anytime soon so a Charley-type track is out of the question. That was a MASSIVE cold front for August.

[Recurve]

DISCLAIMER: This is NOT an official forecast and should not be used as such. It's just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

The GFS SP/Precip chart here shows 1016 high building from florida westward 32 to 56 hours out and a retreat at 60h. Before that there's a trough in the western Gulf, if I'm seeing it right. That does look like no real northward turn, unless it develops right now and if it develops at all and is tracking generally wwd. Thoughts?

http://weather.cod.edu/loops/gfsUS.precip.html

[Sanibel]

Low tracking for now. Must be a ridge tongued into the caribbean after all. That means Yucatan or Belize (if it forms).

[Nimbus]

Mid level center is down around 14N. The TUTT west of 99L may induce some northerly component if the the storm builds into the higher altitude steering pattern.

The GFS is still keeping 99L weak and building the atlantic/caribbean ridge west into the gulf far enough that if the storm does not take root over the warmer SSTs near the Yucatan it could roll in south of the Texas border as a tumbleweed.

There is an upper level high over Arizona that is moving east as the atlantic ridge pushes west. It is not clear to me yet whether the GFS will bridge this high with the atlantic ridge or a TUTT stays between them? If we get a trough near the gulf, forecasting a final track gets very tricky. Troughs can shear or they can help ventilate a developing system. In the current situation a trough near Texas could bias the track further right.