ATL : HARVEY - Tropical Depression - Discussion

[SoupBone]

The one thing to remember is that any model run more than 96 hours (4 days) is subject to constant change from run to run and it's useless to get upset over a "monster ridge" that may end up being very weak or absent - many times folks will jump up and down over a feature like that that shows up on the long-range charts - only to find a day or two later that the ridge is no longer there...

So far the Texas high of all summer is holding firm, so any troughiness will be to it's east and west and so far here in South Florida we are without the strong easterlies - a sure sign the ridge to our northeast is absent...

In fact, all of our weather this week has been coming from west to east, so another sign that a trough is present...

Frank

I believe this is a very reasonable post. I love seeing the long range models, but I always have to remind myself that it's so far off that major errors and changes can occur. I still have trouble believing that the ridge over the Gulf Coast just mysteriously goes away just in time for a storm to hit. I'm not saying it doesn't happen because I know that it does, but this ridge has been ridiculousy dominant.


Are there any other models that show this breakdown in the ridge (aside from the tropical ones)?

[Portastorm]

240 hours or 10 days = science/fiction (lol)...

Looking at the IR loop, it doesn't look as nearly as dire as the TWO is implying - with the exception of one decent but small swirl (92L) and one large swirl that's becoming extratropical (95L), all four invests really aren't that impressive right now:

http://www.goes.noaa.gov/HURRLOOPS/huirloop.html

http://www.ssd.noaa.gov/goes/flt/t1/vis-l.jpg

http://www.ssd.noaa.gov/goes/flt/t2/vis-l.jpg

http://www.ssd.noaa.gov/goes/flt/t3/vis-l.jpg

Using the word "dire" says to me that you interpret the TWO as including language which suggests the proverbial sky is falling. I don't read that at all from the TWO. The forecasters at your old place of employment are merely examining every relevant tropical system in the Atlantic basin and meteorologically evaluating each system's chances at development.

They can't help it if there are a number of active systems. It is mid August after all! So I guess I'm confused why you would think they have issued a "dire" TWO.

[underthwx]

The one thing to remember is that any model run more than 96 hours (4 days) is subject to constant change from run to run and it's useless to get upset over a "monster ridge" that may end up being very weak or absent - many times folks will jump up and down over a feature like that that shows up on the long-range charts - only to find a day or two later that the ridge is no longer there...

So far the Texas high of all summer is holding firm, so any troughiness will be to it's east and west and so far here in South Florida we are without the strong easterlies - a sure sign the ridge to our northeast is absent...

In fact, all of our weather this week has been coming from west to east, so another sign that a trough is present...

Frank

I believe this is a very reasonable post. I love seeing the long range models, but I always have to remind myself that it's so far off that major errors and changes can occur. I still have trouble believing that the ridge over the Gulf Coast just mysteriously goes away just in time for a storm to hit. I'm not saying it doesn't happen because I know that it does, but this ridge has been ridiculousy dominant.


Are there any other models that show this breakdown in the ridge (aside from the tropical ones)?

http://blog.myfoxhurricane.com/wp-conte ... grange.jpg
I dont know if this illustration shows a different perspective, but I hope it helps.

[BigB0882]

I believe this is a very reasonable post. I love seeing the long range models, but I always have to remind myself that it's so far off that major errors and changes can occur. I still have trouble believing that the ridge over the Gulf Coast just mysteriously goes away just in time for a storm to hit. I'm not saying it doesn't happen because I know that it does, but this ridge has been ridiculousy dominant.


Are there any other models that show this breakdown in the ridge (aside from the tropical ones)?

Someone please correct me if I am wrong but I don't think the models show the ridge just breaking down or dying but they show it sliding East? That would open up some parts of the Gulf but the runs don't go out far enough to show landfall, it could be in Mexico.

[underthwx]

https://my.sfwmd.gov/sfwmd/common/image ... orm_92.gif






help me understand why sfwmd models for 92L indicate a recurve, but not 93L?

[Rgv20]

This is the afternoon NWS Brownsville discussion.

.LONG TERM...THE HEAT AND DROUGHT PRODUCING MID LEVEL RIDGE WILL
REMAIN MORE OR LESS ENTRENCHED OVER THE U.S./MEXICO BORDER REGION
UNTIL FURTHER NOTICE RESULTING IN A CONTINUATION OF THE SWELTERING
CONDITIONS. MEAN RH VALUES REMAIN LIMITED UNDER THE RIDGE AXIS
KEEPING THE CONV POPS TO NEAR ZERO. WITH THE ONGOING DROUGHT
CONDITIONS MAINTAINING FAIRLY LOW SOIL MOISTURE VALUES...THE
COMBINATION OF THIS AND THE STRONG DIURNAL HEATING AND HIGH
1000-500 MB THICKNESS VALUES WILL KEEP FAIRLY STATUS QUO MAX/MIN
TEMPS AND NIL POPS THROUGH DAY 7. LOOKING OUT IN THE TROPICS...NHC
IS TRACKING SEVERAL FEATURES ACROSS THE ATLANTIC. THE EASTERNMOST
OF THESE FEATURES MAY MOVE TO NEAR PUERTO RICO BY NEXT THURS. STAY
TUNED TO THE LATEST OUTLOOKS AND FORECAST FROM NHC CONCERNING THE
MOVEMENT OF THIS FEATURE.
&&

[underthwx]

This is the afternoon NWS Brownsville discussion.

.LONG TERM...THE HEAT AND DROUGHT PRODUCING MID LEVEL RIDGE WILL
REMAIN MORE OR LESS ENTRENCHED OVER THE U.S./MEXICO BORDER REGION
UNTIL FURTHER NOTICE RESULTING IN A CONTINUATION OF THE SWELTERING
CONDITIONS. MEAN RH VALUES REMAIN LIMITED UNDER THE RIDGE AXIS
KEEPING THE CONV POPS TO NEAR ZERO. WITH THE ONGOING DROUGHT
CONDITIONS MAINTAINING FAIRLY LOW SOIL MOISTURE VALUES...THE
COMBINATION OF THIS AND THE STRONG DIURNAL HEATING AND HIGH
1000-500 MB THICKNESS VALUES WILL KEEP FAIRLY STATUS QUO MAX/MIN
TEMPS AND NIL POPS THROUGH DAY 7. LOOKING OUT IN THE TROPICS...NHC
IS TRACKING SEVERAL FEATURES ACROSS THE ATLANTIC. THE EASTERNMOST
OF THESE FEATURES MAY MOVE TO NEAR PUERTO RICO BY NEXT THURS. STAY
TUNED TO THE LATEST OUTLOOKS AND FORECAST FROM NHC CONCERNING THE
MOVEMENT OF THIS FEATURE.
&&

EXTENDED...MONDAY THROUGH FRIDAY...MODELS CONTINUE TO KEEP DECENT
MID-LEVEL RIDGING ACROSS SOUTH FLORIDA THROUGH THE WEEK. A RETURN TO
A SLOWLY DEEPENING EASTERLY FLOW PATTER LOOKS MORE PLAUSIBLE BY THE
END OF THE UPCOMING WEEK. THROUGH THE PRESENTLY ANALYZED
WAVES/TROUGHS NOW WELL UPSTREAM ACROSS THE CENTRAL AND EASTERN
ATLANTIC ARE PROGGED TO MOVE MORE NORTHWESTWARD TOWARDS THE WEST
CENTRAL AND NORTHWESTERN ATLANTIC...12Z ECMWF AND GFS MODELS ARE
STILL INDICATING THAT AN INVERTED TROUGH MAY REACH SOUTH FLORIDA AND
THE KEYS LONGITUDE BY WEDNESDAY NIGHT...WITH A FEW ADDITIONAL WEAK
DISTURBANCES OR WAVES MOVING ACROSS THURSDAY AND FRIDAY. THE GFS
FORECAST SOUNDINGS REMAIN QUITE DRY...BELOW 1.50 INCHES AHEAD OF
THIS INDICATED TROUGH FOR MONDAY THROUGH WEDNESDAY...BUT PWAT
RETURNS TO BETWEEN 1.75 AND 2.00 INCHES WEDNESDAY NIGHT AND EVEN
GREATER FOR THE REST OF THE WEEK. SO WILL KEEP CLIMO POPS UNTIL
WEDNESDAY AND KEEP MIDDLE OF THE ROAD CHANCE POPS BY THE PREVIOUS
FORECAST FOR THE REST OF THE WEEK.

and... for what its worth, afternoon Discussion for Key West...93L?


_________________
The following post is NOT an official forecast and should not be used as such. It is 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 including storm2k.org For Official Information please refer to the NHC and NWS products.

[Blown Away]

Sounds like trough moving out and "return to easterly flow by end of upcoming week" means HP building in as 93L reaches the general area.

[StormClouds63]

http://goes.gsfc.nasa.gov/goescolor/goeseast/overview2/color_med/latestfull.jpg

thought this was a good pic.

Great overall perspective ... thanks for the link and it's bookmarked.

[leanne_uk]

Not only is it a great pic you can just see the next possible wave about to exit Africa. Very interesting set up right now

[underthwx]

http://goes.gsfc.nasa.gov/goescolor/goeseast/overview2/color_med/latestfull.jpg

thought this was a good pic.

Great overall perspective ... thanks for the link and it's bookmarked.

Your welcome.......I love that pic....speaks for itself.

[MGC]

93L has some good spin but is currently lacking convection. I expect it to slowly improve its organization....give it a couple of days.

The MJO in my opinion is vastly overrated when it comes to TC formation. I looked at the the MJO phase and TC formation at that time...it was about 50/50 as far as the current phase of the MJO and when the TC formed......MGC

[underthwx]

http://www.beaumontweather.com/93L-1645-081211.gif







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.
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[Typhoon_Willie]

I will attempt to answer your question there underthwx. Now this is my opinion and should not be used as a forecast. As always follow the lastest NHC tropical weather forecasts. First off 93l is further south and east in the Atlantic. Secondly if 92l begins it's predicted recurvature then high pressure will fill in bdhind 92l and thus force 93l on a more westward track. I hope I answered your question there.

[SouthDadeFish]

18Z GFS isn't develop 93L through 96 hours. Add this to the recent weak appearance in satellite imagery and I'm growing skeptical over this storm. Perhaps it will have a better chance in the Caribbean.

[underthwx]

I will attempt to answer your question there underthwx. Now this is my opinion and should not be used as a forecast. As always follow the lastest NHC tropical weather forecasts. First off 93l is further south and east in the Atlantic. Secondly if 92l begins it's predicted recurvature then high pressure will fill in bdhind 92l and thus force 93l on a more westward track. I hope I answered your question there.

Yes you did..93L seems to be a player...we shall see...and...thankyou for your response!






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.
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[SouthDadeFish]

At hour 168 on the 18Z GFS, looks like its trying to develop 93L in the C Carib SE of Jamaica.

[Kohlecane]

At hour 168 on the 18Z GFS, looks like its trying to develop 93L in the C Carib SE of Jamaica.

Interesting, may i have link

[knotimpaired]

https://my.sfwmd.gov/sfwmd/common/images/weather/plots/storm_93.gif
current models....

I know the above is a model from earlier but I have no clue how to post a newer model so for this purpose I will quote it.

I know we have pro mets here, mods and very knowledgeable weather followers. The question is, which of the models do you trust or believe may be more than 70% accurate?

For us that know very little about tutts, ridges and all of the good stuff you know, it would be appreciated to hear your personal opinions in layman’s terms.

[underthwx]

https://my.sfwmd.gov/sfwmd/common/images/weather/plots/storm_93.gif
current models....

I know the above is a model from earlier but I have no clue how to post a newer model so for this purpose I will quote it.

I know we have pro mets here, mods and very knowledgeable weather followers. The question is, which of the models do you trust or believe may be more than 70% accurate?

For us that know very little about tutts, ridges and all of the good stuff you know, it would be appreciated to hear your personal opinions in layman’s terms.

https://my.sfwmd.gov/sfwmd/common/image ... orm_93.gif

heres what I believe is the latest image...simply right click...select copy url image and click it...then when you go back to this forum...and if you make a post....right click again and select paste and you should be good to go...i am not sure if a disclaimer is necessary...i am just a novice...i hope this helps.