Hurricane Florence update

http://www.wunderground.com/tropical/at200606.disc.html#a_topad | NHC Via Wunderground

[dirtboy]

I think it is reasonable at this point to say that historically, most storms in the position of this one at this time of year recurve, a couple have hit the East Coast, and none have hit the Gulf. That gives people in the various regions an idea of how closely they need to monitor it.

Predicting a Carolina landfall at this point is fairly irresponsible - it can get some people needlessly worried this far out who don't know the massive uncertainties of such a forecast.

[Sam Cree]

Thanks for the explanation - very concise and understandable.

[Sam Cree]

Nice website, thank you.

[onthedancefloort]

Indeed, a better use of prediction would be if this even gets out of the TD stage.

IF it does develop, I personally see a track similar to Gloria, with Isabel a close second.

I have my doubts though that this system can even get going.

-t

[brytlea]

I have my fingers in my ears...I can't hear you I can't hear you.... ;)
The bad thing is that they HAVE to close schools if it looks like one is going to hit us, and I don't get paid when we are closed!
susie

[Dog Gone]

Dirtboy gave a pretty thorough explanation, but I'll just elaborate a little.

It is very rare for there to be no shear occuring at all. The air levels are constantly in motion and any tropical system must fight them successfully in order to survive or get larger.

Shear in front of the storm is a much more serious threat than shear coming from another direction, all things being equal. That's because the storm has forward motion, generally between 10 and 20 mph. A storm moving 15 mph into shear of 20 mph is effectively getting hit by 35 mph winds wanting to rip the tops off of the various convection cells within the system.

Sometimes the shear is so severe that it can completely strip the tropical storm naked. That happened to Chris. It was a fairly nice looking tropical storm and the shear increased to the point where it lost all its cloud cover. It was decapitated and never recovered.

Shear is probably the best weapon against a tropical system. Water temperatures can really hurt the storm engine, but that usually doesn't come into play unless a storm follows an earlier one that has churned up the deeper waters and left the surface waters cooler than normal.

[Sam Cree]

Thank you, that makes it even clearer. So, I gather that an atmosphere of shear means that there are mid to upper level winds in the path of the storm which are moving most any direction, but differently than the lower level winds, and are strong enough to literally "shear" the top of the storm off, or at least hack away at it.

[Dog Gone]

You nailed it. Exactly right.

[dirtboy]

Shear is probably the best weapon against a tropical system.

Yep, shear first. Dry air second (helped keep Ernesto down). Cooler water temps third. Jim Cantore being on vacation fourth.

[dirtboy]

The ciculation seems quite elongated WSW to ENE. The invest that was around the Antilles a couple of days ago went from battling dry air to battling shear and got gutted as a result. Let's hope that keeps happening - especially the shear, since the dry air looks less pervasive now than it has all season.

[Dog Gone]

ROFL re Cantore

[dirtboy]

I find Cantore probably the least annoying member of the hurricane hype machine. Plus I admire him sticking it out in that nursing home in Katrina and helping carry vets up to the second floor when the surge was much higher than expected.

[Dog Gone]

Joe Bastardi probably has to be the worst. Every storm has the real potential to obliterate a major American city, maybe even several states, according to him.

I haven't seen his take on this tropical depression yet. I have to assume that he's predicting it to annihilate Houston or New Jersey.

[Howlin]

Are there two of them out there now?

[dirtboy]

There is another tropical wave about 400-500 miles east of the current depression, the forecast I saw was for the depression to absorb that wave. And another wave have just come off the African coast with a defined circulation.

[nwctwx]

Gladys might be an interesting comparison as well. I think something like this is certainly possible here, but the pattern is quite a bit different this go around.

It looks like there is still no certain center with this feature. As with Ernesto, it's impossible to really get any idea about the future till a well defined LLC is cooking.

[Dog Gone]

The NHC is now predicting this depression to become Tropical Storm Florence within the next 24 hours. Most models indicate it won't get close enough to the US to threaten us before heading toward the north Atlantic.

But the models haven't been great this year at all. Ernesto is a great example.

Something is messing with the dynamic models. dirtboy thinks it's El Nino, and that's as good a theory as any I've seen. I'm not clever enough to know.

We'll have to keep on eye on this one, as well as the one emerging from Africa, but I think it's looking pretty hopeful at present.

[Howlin]

Fox News hyping them as "back to back" storms.

[Malacoda]

Do we have a Weather Channel mole who can give us Cantore's travel plans? That's the best way to predict storms.

My husband and I have a "Cantore Scale" -- if Jim Cantore's reporting from your area, you're screwed!

[Dog Gone]

The GFDL doesn't even recognize the creation of a second storm, although it does suggest that soon to be Florence is something to be wary of.

http://moe.met.fsu.edu/cgi-bin/gfdltc2.cgi?time=2006090412-six06l&field=Sea+Level+Pressure&hour=Animation