98L invest,W.GOM,Comments,Sat Pics,Models Thread #3

[LaBreeze]

I had the same squall come through here (Vermilion Parish) PTrackerLA. Lots of rain and very breezy. Rob Perillo on Channel 3 mentioned the possibility that the center may be trying to move a little to the east off of the Texas Coast as we speak. Hmmm, interesting. He is still showing the heavy rain to be over SE Texas. He mentioned dry air moving in from the east over our area. Stay dry!!

[PTrackerLA]

Just watched Rob as well, he seemed convinced this thing would scoot on off into Texas and we'd be dry by tomorrow afternoon. I just don't see this happening with all of the convection still funneling towards Louisiana. Guess we'll see what happens, stay dry!

[wxman57]

Just got home after working from 6:45am to 5:45pm and here I am, looking at the disturbance in the NW Gulf.

To try to explain what's going on, I created a satellite image and identified where the lowest pressure and possible weak LLC is (the "L"), where we have to watch for a possible weak LLC formation (the "X"), and I identified motions of all features with yellow arrows:

http://myweb.cableone.net/nolasue/98Lc.jpg

Lowest pressures and surface wind plots indicate a VERY weak LLC may be located over NW Cameron County to the NW of Harlingen, TX (the "L"). It's been moving to the NNW-N all day but should track generally northward now. At times, we've seen a mid-level circulation ENE-NE of Brownsville but the feature seems to come and go.

Here's a surface map showing the lower pressure area:
http://myweb.cableone.net/nolasue/98Ld.gif

Earlier this morning, a big circular "blob" of storms developed just east of Brownsville. That area died out and another has formed inside the yellow ring on my image above. It's to the left of that blob where I put the red "X" that there could be a slight chance of a weak LLC forming before the system moves ashore tomorrow morning. Note that any low developemt will not change much in terms of potential effects from this disturbance. It's a rain event, not a wind event. Swirl or no swirl at the surface as it moves ashore, rainfall is the threat.

Now a very weak LLC inland over Texas over the next 24-48 hours COULD be a major factor as far as the potential for what we sometimes call a "noctournal core dump". Such rainfall events are more common at night, because all the convergence is focused on a single area and not driven by daytime heating. That's what happened with Allison in 2001 over NE Houston. During the night, a weak area of convergence inland can concentrate all rainfall in a small area, producing incredible amounts of rain if the low is slow-moving. If this disturbance can develop a better-defined LLC then there may be a greater threat of one of these heavy rainfall events somewhere in east Texas.

[Stormcenter]

Look at the eye feature.

http://www.ssd.noaa.gov/goes/east/gmex/loop-vis.html

[stormtruth]

Now a very weak LLC inland over Texas over the next 24-48 hours COULD be a major factor as far as the potential for what we sometimes call a "noctournal core dump". That's what happened with Allison in 2001 over NE Houston. During the night, a weak area of convergence inland can concentrate all rainfall in a small area, producing incredible amounts of rain if the low is slow-moving. If this disturbance can develop a better-defined LLC then there may be a greater threat of one of these heavy rainfall events somewhere in east Texas.

Great explanation and awesome X marks the spot graphic. Thanks for that! Hopefully, the Houston Troplopex will not see another flooding incident.

[Matt-hurricanewatcher]

It looks like the the inland LLC is no longer noticeable. While the possible LLC as Wxman57 pointed out is looking to be taking over with a large area of convection flaring around it. Everything is spinning around that one area around 27-27.5 north/97.5 west. Which is moving northward. The old LLC over land seems to have surged its energy into this area over water. We will have to watch it...The system over all looks like a very large system which should break lots of rain. If that new LLC can develop then we may have something.

[Stratosphere747]

Great stuff 57...

Understand that pressure drops are normal, especially in TStorms, but is the drop seen at the buoy off of Corpus anything to raise an eyebrow at?

http://www.ndbc.noaa.gov/station_page.php?station=42020

[wxman57]

It looks like the the inland LLC is no longer noticeable. While the possible LLC as Wxman57 pointed out is looking to be taking over with a large area of convection flaring around it. Everything is spinning around that one area around 27-27.5 north/97.5 west. Which is moving northward. The old LLC over land seems to have surged its energy into this area over water. We will have to watch it...The system over all looks like a very large system which should break lots of rain. If that new LLC can develop then we may have something.

The inland LLC is the only one I can find using actual surface observations. I can't find any evidence of lower pressure and/or an LLC off the coast. But that area right on the coast where I put the "X" is the place to watch as it moves northward toward the TX coast between CRP and VCT tonight. I estimated a movement of about 360/11, so it won't have much time to do anything.

Most likely, no clear LLC offshore before it moves ashore.

[Stormavoider]

Just got home from work. I left about noon. It doesn't look like I missed anything except a 50 mile NNE shift in the center of this thing. I guess it's 50 miles of favorability for it's chances.

[SouthFloridawx]

So then the circulation apparent on KBRO radar is Mid-Level right?
http://radar.weather.gov/radar.php?rid= ... 1&loop=yes

[Stormcenter]

If it looks like duck, quacks like a duck and swims like a duck. Then it must be___.

[wxman57]

If it looks like duck, quacks like a duck and swims like a duck. Then it must be___.

A tropical disturbance without a well-defined LLC?

[HURAKAN]

If it looks like duck, quacks like a duck and swims like a duck. Then it must be___.

A tropical disturbance without a well-defined LLC?

Remember Claudette in 2003 how good did it look but b/c it didn't have a LLC it took a long time to be upgraded.

[Air Force Met]

Tim was pretty decent while in Dallas but got canned to make room for Dan Henry from D.C. - who IMO is more style than substance. Dan will never have the brain arsenal possessed by David Finfrock.

Or the looks of Kristine Kahanek.

Hey...I went to A&M with Kris. She was president of TAMSCAMS while I was there. Wish I still had my shirt...but it turned into lint a long time ago.

TAMSCAMS=Texas A&M Student Chapter of the AMS.

[wxman57]

So then the circulation apparent on KBRO radar is Mid-Level right?
http://radar.weather.gov/radar.php?rid= ... 1&loop=yes

I believe you need to look at a longer loop, perhaps 3 hours. I can see a broad mid-level spin about 120 miles across centered inland NW of Brownsville. There's one flare-up of squalls on the eastern periphery of this ring, probably what you're referring to as the circulation. But I'm not sure if there is a circulation aloft there. Could be, but it could also be that the decaying squall sent out an outflow boundary to the south that makes it look like a spin. Really hard to tell.

In any case, echoes that far from radar are well above the surface. My current software doesn't let me measure beam height, but I'd estimage the beam is maybe at 7000- 10,000 feet or so at that distance from BRO.

[Matt-hurricanewatcher]

Last year everything was in place for development. In storms got lucky this year the storms are unlucky. Which nothing will develop intill that luck changes. But yes this should have at least some chance before it makes it inland. I would watch the surface obs if they show that the inland low weakens and a LLC is forming over the water. Which visible is trending to show then the story may change.

[Stormavoider]

Look at the eye feature.

http://www.ssd.noaa.gov/goes/east/gmex/loop-vis.html

If it's still that evident on the 23:45 and 00:15 frames, LOOK OUT CORPUS!!!

[wxman57]

Tim was pretty decent while in Dallas but got canned to make room for Dan Henry from D.C. - who IMO is more style than substance. Dan will never have the brain arsenal possessed by David Finfrock.

Or the looks of Kristine Kahanek.

Hey...I went to A&M with Kris. She was president of TAMSCAMS while I was there. Wish I still had my shirt...but it turned into lint a long time ago.

TAMSCAMS=Texas A&M Student Chapter of the AMS.

I was president of TAMSCAMS from 1979-1980.

[gboudx]

Tim was pretty decent while in Dallas but got canned to make room for Dan Henry from D.C. - who IMO is more style than substance. Dan will never have the brain arsenal possessed by David Finfrock.

Or the looks of Kristine Kahanek.

Hey...I went to A&M with Kris. She was president of TAMSCAMS while I was there. Wish I still had my shirt...but it turned into lint a long time ago.

TAMSCAMS=Texas A&M Student Chapter of the AMS.

I've told my wife that I bet Kristine was pretty popular in meteorology school. I bet she didn't have much trouble finding lab partners.

That said, she's not just a pretty face on TV. She knows what she's talking about, hence being the Chief Meteorologist at KTXT here in DFW.

[Stormcenter]

If it looks like duck, quacks like a duck and swims like a duck. Then it must be___.

A tropical disturbance without a well-defined LLC?

You mean a VERY impressive tropical disturbance.