ATL GUSTAV: Tropical Depression - Discussion

[CourierPR]

Will that ULL to Gustav's northeast have a role to play? It seems like many posters are ignoring it.

If Gustav moves slowly enough it might. If he moves as forecast, not really.

That ULL appears to be diving SW rapidly.

[Stormcenter]

>>Now this is an excellent post. You can't fight climatology and I believe it's working in the central GOM's favor.

Yeah, but climatology says that it's not going to snow in New Orleans and especially not on Christmas Day. Enter Christmas 2004. You never know. Glad the early trends are this way so we can watch them evolve elsewhere.

Steve

Yes but it has snowed before on Christmas in N.O. before 2004 but this Gustav senario for LA. has NEVER happened before per climatology.

So since the models seem to be indicating a threat towards LA just because there isn't a record of a similar track in our brief history of record keeping we can discount that? I just don't understand the obsession with climatology sometimes. Bertha was perfectly normal this year right? There's been multiple years this decade that have completely shown no regard for climatology either. With that being said, it's a little comforting knowing models will change and to be targeted this far out makes me feel better. Texas to Florida Panhandle are all under the gun IMO.

No obsession with climatology just stating that it is in LA. favor. That doesn't mean it can't happen only that it is not likely based on climatology (or passed history). By the way, I agree with your "who's under gun" comment.

[KWT]

CourierPR, I don't see it diving SW, all I see is it wrapping around moisture making it look like its moving SW. Development of the block should stop any closer movement of that circulation in the next 24hrs.

[TreasureIslandFLGal]

Go here: http://www.hpc.ncep.noaa.gov/medr/day7nav_pre.html

That shows very simply the dynamics from day 3 to day 7 down the road.

Day 7 makes it look like a north central gulf coast hit is not probable.

This is a sight put out by the Hydrometeorological Prediction Center (HPC). Their focus is not really tropical storms, but the fronts, troughs, and ridges that move around the conus. They serve to predict weather systems stateside.

I use this to see what the ridges and fronts/trough are expected to be doing in a few days.

Looking at this, I wonder how cyclones can go where some of the tropical models say they will go. It is as if they are ignorant of the rest of the weather around them sometimes, or as if this sort of data isn't ingested into the models before they run.

of course...this too is just a conglomeration of models.

[gatorcane]

KWT the TUTT is definitely diving SW. You can see here. If Gustav does not get moving, maybe the shear will start increasing over it.

http://metofis.rsmas.miami.edu/~dortt/s ... 1_loop.gif

[ConvergenceZone]

:uarrow:

KWT the TUTT is definitely diving SW. You can see here. If Gustav does not get moving, maybe the shear will start increasing over it.

http://metofis.rsmas.miami.edu/~dortt/s ... 1_loop.gif

totally agree...

[KWT]

Its not going to get there in time Gatorcane to increase shear, note the eastern side of the upper high is already nearly over Gustav, should see this bending to the WNW very soon indeed, if not already showing hints of that motion.

The reason motion has slowed is simply because its now in the weak steering currents between the trough and the upper high, but I'm certain that this now moves WNW within the next 6-12hrs.

[HouTXmetro]

Go here: http://www.hpc.ncep.noaa.gov/medr/day7nav_pre.html

That shows very simply the dynamics from day 3 to day 7 down the road.

Day 7 makes it look like a north central gulf coast hit is not probable.

This is a sight put out by the Hydrometeorological Prediction Center (HPC). Their focus is not really tropical storms, but the fronts, troughs, and ridges that move around the conus. They serve to predict weather systems stateside.

I use this to see what the ridges and fronts/trough are expected to be doing in a few days.

Looking at this, I wonder how cyclones can go where some of the tropical models say they will go. It is as if they are ignorant of the rest of the weather around them sometimes, or as if this sort of data isn't ingested into the models before they run.

of course...this too is just a conglomeration of models.

Day 7 shows a stalled Front which means the High Presure could actually build and shoot Gustav off Further west. Right?

[rockyman]

Go here: http://www.hpc.ncep.noaa.gov/medr/day7nav_pre.html

That shows very simply the dynamics from day 3 to day 7 down the road.

Day 7 makes it look like a north central gulf coast hit is not probable.

Not probable? I see a system south of PNS moving NNW...are you thinking the front would turn it NE or east? No models are showing that setup right now. Or are you thinking that a building high behind the front would turn the system back to the west?

[senorpepr]

Personally, I think many put the wrong type of emphases on climatology. Climatology is a great tool, but it's not definitive. Too many people look at climatology and follow it directly. "Climatology says we won't get snow, so we will NOT get snow." Climatology is nothing more than an average, or normal. I like to consider it like gambling. I get the advantage from the house whenever I use climatology. Will I be absolutely right? No. But climatology lays out a general guideline that will work pretty well.

For instance, to say a storm will NOT go to a given location because of climatology, and climatology alone... that is foolish. Climatology may suggest that it will not happen, but you must apply it to the dynamic situation.

Another issue I see, a lot of folks completely toss out climatology because of one line in a forecast discussion back a few years ago. (see Emily 2005 discussion #8) "...THE 2005 HURRICANE SEASON SEEMS TO HAVE LITTLE INTEREST IN CLIMATOLOGY." Believe it or not, 2005 still fit many climatological guidelines, although the nay-sayers may disagree. Matter of fact, using a climatological curve based on the activity witnessed, climatology predicted 25-30 named storms in July. The key is you have to apply climatology appropriately to the dynamic situation.


When ever the debate of climatology comes up, I'm reminded of a few situations from the job. First, during my first week of forecasting, I was producing forecasts for the Rhine River Valley of Germany. It was August, we were under high-pressure, and the temperatures were flirting with records highs. We were reminded that climatology sets the guideline of what the temperature should be. (Normally it's in the mid-80s, normally it never exceeds 100...) We shouldn't stray too much from climatology UNLESS dynamics say otherwise. (In this case, the dynamics called for record temperatures.)

Another example is from a tropical class I attended. The general rule of the tropics is always climatology and persistence, unless something dynamic occurs. Even then, the system will tend to follow climatology for that given pattern.

[93superstorm]

I still see some kind of wnw movement on. Could be a wobble? Also Does anyone have any current reports in Haiti or some kind of radar?

[carversteve]

In my unofficial opinion and to my untrained eye..it does seem to be moving west on the last frame of the visible.

[cycloneye]

The latest:

[Steve]

Assuming StormKat is WGNO ABC 26 Chief Met Bruce Katz. ( )
------------------------------
Thanks seniorpepr. On top of everything else, our records even going back pre-1960's (age of the satellite era) are sketchy. Western man has only been in North America permanently for some 450-500 years while North America has been around for millions of years in its current but changing state. All the soil borings in the world - especially coastal locations - aren't going to tell us exactly what absolute parameters might exist within the weather. For instance, it may be reasonble that during the ice age, my local had a mean temp of 30 degrees. Maybe in hotter times, it was up in the low 100's. Nobody knows. We can't know. A footprint of a few centuries on a rock that is billions of years old and has changed format many times just isn't a large enough of a sample to base anything on climatology except what you said - simple averages and norms.

Steve

[KWT]

Well its hard to say but to me the motion looks around 300, though the eye is only small and not super well defined so it may be a little off.

Still I think Haiti will weaken Gustav fairly readily though the amount of time likely overland will probably allow it to keep much of its inner core.

[Sabanic]

I can see everyone scrutinziing every single move when Gustav gets further up into the Gulf, but at this point every little wobble doesn't necessarily mean anything. We still have a few days before we need to worry ourselves with even the slightest movement.

Keep your sanity in tact for now. You may REALLY need it in a few days.

[mvtrucking]

In my unofficial opinion and to my untrained eye..it does seem to be moving west on the last frame of the visible.

Or just a tad north of west. Pretty close to that in the last frame or so.JMO

[TreasureIslandFLGal]

Ugh.. I posted a whole and it lost it.

Here's what I am watching...95L is going to be a telling factor.

This can do 2 things ultimately... either go NE over Florida or go WNW into TX. If this stalls for a time, 95 L will be impacting the ridge over florida. It may bolster it or it may weaken it.

If Gustav stalls for a long time, then the weakness will develop and it will eventually head across cuba near Havana, then finds the weakness, and heads N and NE over florida (next week like Tues evening or Wednesday) south of that front.

OR... this goes slow and steady towards the west, possibly even WSW towards the Yucatan and then to the TX/MX as the ridge stays strong. The ridge could actually continue to build a bit towards the west as 95L causes it to bolster on the opposite side of 95L "leaning" on it. In any case, I think the northern gulf is safe on this one as I see things right now. Of course, all this is subject to change, especially in the even of system stalling! I'm no pro and you need to pay attention to official forecasts...blah blah blah. In any case, stay safe all and pay attention to this one!

[Aquawind]

I can see everyone scrutinziing every single move when Gustav gets further up into the Gulf, but at this point every little wobble doesn't necessarily mean anything. We still have a few days before we need to worry ourselves with even the slightest movement.

Keep your sanity in tact for now. You may REALLY need it in a few days.

Yep.. But they just can't help it..lol No really it's a hurricane wobble and movement/wobble confusion is normal as it is frustrating. Many live on the edge of insanity on a daily basis so no worries..lol

Good Stuff on Climatology senorpepr!

[Chigger_Lopez]

If Gustav doesnt move as quickly as progged, is it not quite possible for the dynamics to change to allow the storm to move North into some sort of weakness. Or, cant the dynamics end up not being exactly like they are forecasted to be right now. Does anyone remember Ernesto and how things change quickly. I understand the ridge IS HERE now and looks solid, but things can change right? I am not -removed- a Florida hit, just asking a question of how certain a Gulf hit is?