ATL: TROPICAL DEPRESSION ALEX - DISCUSSION

[lrak]

It is a bit surreal to see my town in the NHC wind probability chart. Doesn't happen too often (thankfully).

My parents live right along the beach in Port Aransas. I don't like this one bit. These things are suppose to go North! Nothing against my Northern friends

[ozonepete]

And then down to 6 knots at a place of 985.3 mb! Then, when they start seeing higher pressures, the winds pick up. VERY interesting. I'll say it again, eye forming?

-Andrew92

Not necessarily, cyclones of any strength have a calm region at there center, even tropical depressions. Only hurricanes develop a cloud-free area around their center, however. That being said, with a pressure fall of 2 mb between passes, and the deep convection forming over the center, it probably wont be long before we start seeing an eye-feature. Just my 2 cents!

Just to clarify it is TROPICAL cyclones. Mid-latitude and polar cyclones do not, in most cases, have calm centers.

[Air Force Met]

To address your first question, the whole thing about "fronts" steering tropical systems is simplistic, and really a misnomer perpetuated by meteorologists who are either too ignorant or too lazy to explain what is actually happening.

And he comes out swinging!

[Wx_Warrior]

Delta...you are a flipper...

[TwisterFanatic]

It's like I said earlier, with the stall that the models were not indicating and the jog northward you could pretty much throw out the old model runs. This movement to the north changes the outcome and if this movement continues it could be large!!

The NHC shows a sharp left turn tomorrow but i am not so sure that is going to happen now.

[deltadog03]

Delta...you are a flipper...

LOL...not too much...I thought either side of BRO would be the landing area for alex. Ya, I did go up just a little bit.

[Dean4Storms]

It's like I said earlier, with the stall that the models were not indicating and the jog northward you could pretty much throw out the old model runs. This movement to the north changes the outcome and if this movement continues it could be large!!

I should have also added speed. If the Gulf Ridge is breaking down really fast then Alex could really accelerate while keeping this heading, that could make a BIG difference.

[summersquall]

I want to thank from the bottom of my heart the time and energy all on this board, particularly the pros take to share their knowledge with us.

I love weather and want to learn and you all are awesome.

I wish us all a safe and interesting season.

God Bless.

[hurricaneCW]

I'm surprised the NHC only shows it strengthening to 80 knots, I would think at least 90 knots would make more sense considering the favorable environment expected.

[HURAKAN]

Latest

[Texas Snowman]

IF you ask me this is starting to look more like a Texas storm...

LOL!!!

I'm not laughing at you TwisterFanatic, just at what you said. Because it wasn't too long ago this evening that someone posted that this was looking more and more like a Mexico storm!

Bottom line, Alex isn't necessarily playing by the rule book. I think anything from Rockport to NE Mexico is in play with this one for a potential landfall.

[timNms]

However, what's going to happen with the front. Is it going to wash out (or retreat back as a warm front) and allow Alex to turn west?

I also have read that a high is supposed to be building in to the north, but in order for that to happen and it have an effect on Alex's path, wouldn't the front have to be out of the way?

When thinking of steering for tropical systems...you must think higher than the surface. Fronts are surface features. Fronts don't turn hurricanes...its the upper level winds that brings the fronts down in the first place (upper level trofs and lows) that do that. A front will, however, because of cold air convection, weaken a ridge aloft...and create a weakness.

The high that is supposed to be building (and is building over the Rockies) is not at the sfc...but up at around 18,000 feet. Fronts move out of the way when high like that build because of sinking air and other thermo-dynamic phenom. that is frankley very complicated to explain and I would be here all night...

Thanks, AFM. I knew it had to be much more complicated than what I'd posted. I appreciate your time.
Let's see if I understand a little better. The front that is moving westward is being driven by an upper level trough that has/is creating a weakness in the high (along with that ULL that's over SE LA). This has allowed a more northward motion in Alex over the past few hours.
What is going to happen to the trough that is driving the front as the high builds back in? (Stupid question?)

[HouTXmetro]

It's like I said earlier, with the stall that the models were not indicating and the jog northward you could pretty much throw out the old model runs. This movement to the north changes the outcome and if this movement continues it could be large!!

I should have also added speed. If the Gulf Ridge is breaking down really fast then Alex could really accelerate while keeping this heading, that could make a BIG difference.

Looks like he is accelerating now to me.

[AJC3]

To address your first question, the whole thing about "fronts" steering tropical systems is simplistic, and really a misnomer perpetuated by meteorologists who are either too ignorant or too lazy to explain what is actually happening.

And he comes out swinging!

I figured you'd like that!

[Dean4Storms]

It's like I said earlier, with the stall that the models were not indicating and the jog northward you could pretty much throw out the old model runs. This movement to the north changes the outcome and if this movement continues it could be large!!

I should have also added speed. If the Gulf Ridge is breaking down really fast then Alex could really accelerate while keeping this heading, that could make a BIG difference.

Looks like he is accelerating now to me.

I noticed that too, could be a bad sign IMO.

[TwisterFanatic]

IF you ask me this is starting to look more like a Texas storm...

LOL!!!

I'm not laughing at you TwisterFanatic, just at what you said. Because it wasn't too long ago this evening that someone posted that this was looking more and more like a Mexico storm!

Bottom line, Alex isn't necessarily playing by the rule book. I think anything from Rockport to NE Mexico is in play with this one for a potential landfall.

Your laughing at me because im a n00b. lol

[Texas Snowman]

IF you ask me this is starting to look more like a Texas storm...

LOL!!!

I'm not laughing at you TwisterFanatic, just at what you said. Because it wasn't too long ago this evening that someone posted that this was looking more and more like a Mexico storm!

Bottom line, Alex isn't necessarily playing by the rule book. I think anything from Rockport to NE Mexico is in play with this one for a potential landfall.

Your laughing at me because im a n00b. lol

Nope, I'm laughing because you can tell it is full blown hurricane season now. We're all in wobble watching mode!!!

[timNms]

I posted this on the model thread but no one has answered. Question for AFM or anyone with some expertise.

We've got a front moving in and an ULL over MS/LA. I'm assuming the ULL is going to continue to move eastward and get outta the way. However, what's going to happen with the front. Is it going to wash out (or retreat back as a warm front) and allow Alex to turn west?
Local NWS here is saying the front is going to stall out around the I 20 corridor in MS and hang out for a few days.

Correct me if I'm wrong here, but don't fronts tend to steer tropical systems? I don't recall ever hearing of a tropical system crossing a front. If the front doesn't wash out or retreat to the north, what happens to Alex and his track? I also have read that a high is supposed to be building in to the north, but in order for that to happen and it have an effect on Alex's path, wouldn't the front have to be out of the way?

To address your first question, the whole thing about "fronts" steering tropical systems is simplistic, and really a misnomer perpetuated by meteorologists who are either too ignorant or too lazy to explain what is actually happening. A front is nothing more than a boundary between air masses. Tropical cyclones are steered by mean layer winds, the depth of which depends on how vertically deep/coherent (i.e. strong) the cyclone is.

Fronts don't magically attract or deflect storms. Not all fronts are created equal and the mid and upper air pattern can vary greatly above the surface. Strong cold fronts are usually oriented more meridionally (N-S) and associated with strongly amplified (sharp or deep) mid and upper level troughs which in turn create a deep layer of southerly and southwest flow which is sufficient to recurve a cyclone. Weak fronts (generally oriented more zonally E-W) are associated with weak upper troughs which are usually not sufficient to recurve a TC. A lot also depends on the position of the front and it's parent mid-upper level trough in relation to the TC.

In short, look at more than the fact that there's a front there. Look at more levels (850MB, 700MB, 500MB, etc.) to gauge more accurately what effect an area near a cold front might have on a TC.

Thanks, AJC. I learned something new tonight from you and AFM.

[Dean4Storms]

However, what's going to happen with the front. Is it going to wash out (or retreat back as a warm front) and allow Alex to turn west?

I also have read that a high is supposed to be building in to the north, but in order for that to happen and it have an effect on Alex's path, wouldn't the front have to be out of the way?

When thinking of steering for tropical systems...you must think higher than the surface. Fronts are surface features. Fronts don't turn hurricanes...its the upper level winds that brings the fronts down in the first place (upper level trofs and lows) that do that. A front will, however, because of cold air convection, weaken a ridge aloft...and create a weakness.

The high that is supposed to be building (and is building over the Rockies) is not at the sfc...but up at around 18,000 feet. Fronts move out of the way when high like that build because of sinking air and other thermo-dynamic phenom. that is frankley very complicated to explain and I would be here all night...

Thanks, AFM. I knew it had to be much more complicated than what I'd posted. I appreciate your time.
Let's see if I understand a little better. The front that is moving westward is being driven by an upper level trough that has/is creating a weakness in the high (along with that ULL that's over SE LA). This has allowed a more northward motion in Alex over the past few hours.
What is going to happen to the trough that is driving the front as the high builds back in? (Stupid question?)

This trough should head into eastern Canada or off the NE Seaboard, that is why the front is expected to wash out north of the Gulf Coast.

[cycloneye]

Irak,you better prepare there as that area may get much of it,even if the center passes well to the south of CC.