Page 10 of 26

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 9:43 am
by MontgomeryCoWx
My personal feeling (and I'm not a pro met mind you) is this is headed toward a Lake Charles to Biloxi window.

The models are struggling mightily with this and that ridge isn't breaking down like they want it to.

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 9:46 am
by srainhoutx
08252016 Eric Blake Cqtk0WpVMAAeFGO.jpg
Eric Blake ‏@EricBlake12 · 12m
The @53d_HHA dropsonde flight around #99L starts soon- data should make the 18/00z model cycles- HT @ChrisLandsea

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 9:48 am
by Andrew

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 9:48 am
by CrashTestDummy
There's a pretty good amount of shear where 99L is now, which is probably contributing to the lack of development. As it moves westward, it will be moving into an area of less shear, which may help it to develop some.

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 10:26 am
by stormlover
Great break down from Meterologist Travis Herzog:
Tropical uncertainy remains high, comparisons to Ike and Rita, and is there a connection between summer rains at Hobby Airport and tropical activity over Texas?
I've got a lot of interesting tidbits to share with you, but I'll try to keep it brief.
As of Thursday morning, the tropical disturbance remains poorly organized. High wind shear coming from the Bahamas is pushing the storms south over Hispaniola. For a tropical disturbance to develop, the storms have to form over the center. That wind shear is expected to slowly decrease between now and Saturday, which should increase the chances this develops into Hermine over the weekend.
Overnight, the computer model tracks started to cluster over Florida, with only a few into the eastern Gulf of Mexico. Now as the Thursday morning computer model tracks trickle in, we're seeing more shift back into the western Gulf of Mexico.
So which ones do we believe? Right now, it's impossible to say. Until a trackable depression or storm actually develops, they're all just guessing with really sophisticated calculus equations.
For now, we continue to just keep you aware and informed while uncertainty remains high.
Some have asked about comparisons to Ike and Rita. I think it's a fair question to ask. Why? Most storms in the Bahamas don't come to Texas. Ike and Rita did.
The current position of this disturbance is actually located in the exact spot Ike crossed over in 2008 and very near where Rita formed in 2005, but that really tells us nothing about what *this* storm will do.
Ike was a completley different setup, already a major category 4 hurricane and barreling westward toward Cuba.
Rita did form in almost this exact location, and the upper level steering flow is somewhat similar. That's where the comparion ends. All this tells me is that a path toward Texas is possible based solely on history, but it says nothing about the current state of the atmosphere and what this thing will eventually do.
So this is no Ike, but there are shades of Rita.
Finally, this was an interesting connection I made this morning, but I have no idea if it means anything for us in the future.
Our local National Weather Service office pointed at that today Hobby Airport could break it's streak of longest consecutive days with measurable rain. That streak currently stands at 12. When you look at the other four years in the top 5 list, they all occurred during summers when Texas was impacted by named tropical systems:
2008 - Ike, Dolly, Edouard
2005 - Rita
2001 - Allison
1968 - Candy
Let's hope we break that connection in 2016.

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 10:28 am
by CrashTestDummy
Andrew wrote:Large rapid visible loop here:

http://rammb.cira.colostate.edu/ramsdis ... peed_ms=80
Awesome images! It's incredible to see that thunderstorm build up just west of Great Inagua Island in the Bahamas. Like a volcanic eruption! Thanks for sharing.

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 11:08 am
by sambucol
Are any models ran during the day?

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 11:19 am
by stormlover
GFS shows nothing lol, but the Ridge is stronger!!

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 11:26 am
by Skyguy
stormlover wrote:Great break down from Meterologist Travis Herzog:
Tropical uncertainy remains high, comparisons to Ike and Rita, and is there a connection between summer rains at Hobby Airport and tropical activity over Texas?
I've got a lot of interesting tidbits to share with you, but I'll try to keep it brief.
As of Thursday morning, the tropical disturbance remains poorly organized. High wind shear coming from the Bahamas is pushing the storms south over Hispaniola. For a tropical disturbance to develop, the storms have to form over the center. That wind shear is expected to slowly decrease between now and Saturday, which should increase the chances this develops into Hermine over the weekend.
Overnight, the computer model tracks started to cluster over Florida, with only a few into the eastern Gulf of Mexico. Now as the Thursday morning computer model tracks trickle in, we're seeing more shift back into the western Gulf of Mexico.
So which ones do we believe? Right now, it's impossible to say. Until a trackable depression or storm actually develops, they're all just guessing with really sophisticated calculus equations.
For now, we continue to just keep you aware and informed while uncertainty remains high.
Some have asked about comparisons to Ike and Rita. I think it's a fair question to ask. Why? Most storms in the Bahamas don't come to Texas. Ike and Rita did.
The current position of this disturbance is actually located in the exact spot Ike crossed over in 2008 and very near where Rita formed in 2005, but that really tells us nothing about what *this* storm will do.
Ike was a completley different setup, already a major category 4 hurricane and barreling westward toward Cuba.
Rita did form in almost this exact location, and the upper level steering flow is somewhat similar. That's where the comparion ends. All this tells me is that a path toward Texas is possible based solely on history, but it says nothing about the current state of the atmosphere and what this thing will eventually do.
So this is no Ike, but there are shades of Rita.
Finally, this was an interesting connection I made this morning, but I have no idea if it means anything for us in the future.
Our local National Weather Service office pointed at that today Hobby Airport could break it's streak of longest consecutive days with measurable rain. That streak currently stands at 12. When you look at the other four years in the top 5 list, they all occurred during summers when Texas was impacted by named tropical systems:
2008 - Ike, Dolly, Edouard
2005 - Rita
2001 - Allison"
1968 - Candy
Let's hope we break that connection in 2016.
Where is Travis Hertzog getting these models? The Euro still points it toward Florida. I do not see any evidence of a shift toward our region.

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 11:35 am
by Andrew
sambucol wrote:Are any models ran during the day?

Most models run every 6 hours and some, like the ECMWF run every 12 hours. Currently the GFS is finishing up and the ECMWF will run in the next couple hours.

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 11:38 am
by Scott747
srainhoutx wrote:
sambucol wrote:Srain, does this mean the models will trend back to the west again due to the stout ridge?
There was a slight shift West with the 12Z track guidance. I would rather wait until we have an actual storm declared and at least another 24 to 48 hours after TC genesis to get a better 'feel' of the synoptic pattern across the Nation. Scott mentioned yesterday that the various models may settle down with the wild run to run swings beginning around 00z tonight. I agree with his assessment.
I'm trying and impatiently waiting for the 0z models before chiming in much more though I saw your post about the sonde drops possibly making that 18z runs - Which should start resolving some of the issues.

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 11:44 am
by Andrew
GFS shows no development, UKMET and CMC shifted west with weak/moderate development.

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 11:59 am
by DoctorMu
Yeah, the GFS is pure lemonade.

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 12:18 pm
by jasons2k
Regarding the Hobby Rainfall correlation summary from Mr. Herzog:

I think it's probably not a good idea to send a thought/opinion/whatever about a topic like this without some more thorough research and vetting. A scientist should know better IMO.

Distilled to one thought: the post is trying to establish some sort of causal relationship between consecutive rainfall observations @ Hobby and tropical cyclones as a factor in predicting odds of a cyclone impact on the Upper TX Coast the rest of this season.

The problem with the sample data, is that in many of those cases, the rainfall was actually a result, not a cause or predictor, of cyclone activity.

I'm actually pretty shocked to see this published, anywhere.

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 12:39 pm
by brooksgarner
I just saw that post where T.H. wrote about how record consecutive measurable rains at Hobby could be a sign of an impending tropical system... In his defense, I'm fairly certain he was using a bit of sarcasm to say that, "basing long-range tropical forecasts on analogues of where previous storms may have tracked is not always a reliable solution". I read that to continue his critique that most analogue-based long-range forecasts are hogwash. He was basically evoking the whole, teleconnection = fiction argument: "if a butterfly flaps its wings in Indonesia, a cat 5 hurricane will strike Bermuda". Obviously there's probably no connection between rainy days in Houston and a guaranteed hurricane strike.

Son I don't believe T.H. was being, irresponsible to initiate a conversation about analogue forecasting... The only thing I've seen which to me is irresponsible is a meteorologist posting a single model solution from a single model run showing 99L definitively striking as a major hurricane, 10 days out, in [insert coastal city of choice.] Any true met knows that there is no way to be certain of location of impact, much less intensity. Doing so is simply appealing to the many weather-uneducated out in the world, for a petty attempt at a ratings grab. If something like that is posted by a verified meteorologist, it would be a dishonest and unethical move. That said, I've seen a few TV people from other markets post stuff like that to twitter and facebook.

All that said and 99L aside, anyone watching that little tropical low progged to develop in the western Gulf this weekend? EURO, WRF-ARW, NAM showing a low that would enhance our rainfall. It's a sleeper but needs to be watched too, for its heavy rain potential if nothing else.

See you guys soon on the TV side ...

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 12:53 pm
by srainhoutx
08252016 Eric Blake Shear CqtwWj7VUAAcseX.jpg
Eric Blake ‏@EricBlake12 · 2h2 hours ago
The #99L SHIPS 12Z model is revealing- Note forecast shear falling from high (red) now to low (green) this weekend


Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 1:07 pm
by jasons2k
brooksgarner wrote:I just saw that post where T.H. wrote about how record consecutive measurable rains at Hobby could be a sign of an impending tropical system... In his defense, I'm fairly certain he was using a bit of sarcasm to say that, "basing long-range tropical forecasts on analogues of where previous storms may have tracked is not always a reliable solution". I read that to continue his critique that most analogue-based long-range forecasts are hogwash. He was basically evoking the whole, teleconnection = fiction argument: "if a butterfly flaps its wings in Indonesia, a cat 5 hurricane will strike Bermuda". Obviously there's probably no connection between rainy days in Houston and a guaranteed hurricane strike.

To add my 2 cents to the previous poster's comment: I don't believe T.H. was being, "irresponsible" to initiate a conversation about analogue forecasting... The only thing I've seen which to me is irresponsible is a meteorologist posting a single model solution from a single model run showing 99L definitively striking as a major hurricane, 10 days out, in [insert coastal city of choice.] Any true met knows that there is no way to be certain of location of impact, much less intensity. Doing so is simply appealing to the many weather-uneducated out in the world, for a petty attempt at a ratings grab. If something like that is posted by a verified meteorologist, it would be a dishonest and unethical move. That said, I've seen a few TV people from other markets post stuff like that to twitter and facebook.

All that said and 99L aside, anyone watching that little tropical low progged to develop in the western Gulf this weekend? EURO, WRF-ARW, NAM showing a low that would enhance our rainfall. It's a sleeper but needs to be watched too, for its heavy rain potential if nothing else.

See you guys soon on the TV side ...
FWIW I was careful to not use the word "irresponsible" as I thought that was a bit too strong of a critique.

I didn't say that - I choose my words carefully.

Somewhere in the post I missed the sarcasm, so my apologies if I misinterpreted it to mean something else.

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 1:13 pm
by Andrew
ECMWF a lot weaker on the 12z run so far. Similar track though to 00z. Maybe a little south.

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 1:18 pm
by brooksgarner
I saw the word and now I don't. The post must have been edited. The word(s) used was either, "irresponsible" or "not responsible."

I know Travis well enough to know that he is very smart and would not suggest that rainy days at Hobby would have a serious correlation to getting hit by a tropical system. I read it as he was just taking the comparison sarcasm all the way. I guess he could've added that heavier than normal traffic on 290 could be an indicator. (At least that would be true: evactuation, contra-flow!. :lol:
FWIW I was careful to not use the word "irresponsible" as I thought that was a bit too strong of a critique.

I didn't say that - I choose my words carefully.

Somewhere in the post I missed the sarcasm, so my apologies if I misinterpreted it to mean something else.

Re: Tracking the Tropics: Hurricane Gaston & INVEST 99L

Posted: Thu Aug 25, 2016 1:18 pm
by jasons2k
Andrew wrote:ECMWF a lot weaker on the 12z run so far. Similar track though to 00z. Maybe a little south.
Not really surprising given the trend, will stay weaker and on the SW side of guidance until it gels, prob not until the FL Straits IMO.