TS Florence,Analysis,Sat Pics Thread #7

[kenl01]

I guess surfers alog the mid ATL and NE shores could enjoy some good swells.
Other than that, I don't expect much from Florence in the US...........

[carve]

I'm from ohio and still wonder about the continued wnw movement..a few days ago it was forecasted to have turned already....so is it possible that the turn may come even further west..?It is past 60 degrees west already..most said it would turn before that..and it's not up to 25 north yet is it?..just curious

[wxman57]

Looking at [url=http://wwwghcc.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20CONUS&lat=25&lon=-61&map=latlon&quality=100%&info=vis&zoom=1&width=2800&height=2000&type=Animation&numframes=8&palette=ir.pal]this big visible loop[/url], it seems to be moving almost due west for the past hour.

The loop is a bit short, but I don't see a westerly movement. Look at the lower part of the CDO, it moves farther north with each image.

[storms in NC]

Just because people are concerned about the possibility that this storm could defy atmospheric logic and continue on a more westward track may not necessarily mean that they are wishing it upon themselves.

This is very true. They see it is moving west and just want to know if it will go up the middle and not bother Bermuda that much. I think everyone knows it will not HIT Fla or the whole East coast. Just up the middle. well that is what I have been thinking about any way.

[wxman57]

I'm from ohio and still wonder about the continued wnw movement..a few days ago it was forecasted to have turned already....so is it possible that the turn may come even further west..?It is past 60 degrees west already..most said it would turn before that..and it's not up to 25 north yet is it?..just curious

The turn was not forecast to be something you'd immediately notice. As I've said before, expect a gradual change in heading today toward a more NW direction. By late afternoon, I expect about a 20-30 deg. change in heading. It'll occur so gradually that you won't notice it. The more northward track has always been forecast to occur between 65W and 68W.

[wxman57]

Wxman57, I believe this was asked before, but I didn't see the answer. What are the possibilities of her pulling a loop like the BAMs are depicting?

Somewhere close to the odds of it moving southwest into the Caribbean, about 1 in 1,000,000,000,000,000,000.

[Meso]

If the GFDL's 06z run verify,Bermuda could have Tropical Storm force winds for just under 30 hours with the strongest part of the storm right over it.

http://moe.met.fsu.edu/tcgengifs/gfdl/2 ... /slp10.png

[carve]

I'm from ohio and still wonder about the continued wnw movement..a few days ago it was forecasted to have turned already....so is it possible that the turn may come even further west..?It is past 60 degrees west already..most said it would turn before that..and it's not up to 25 north yet is it?..just curious

The turn was not forecast to be something you'd immediately notice. As I've said before, expect a gradual change in heading today toward a more NW direction. By late afternoon, I expect about a 20-30 deg. change in heading. It'll occur so gradually that you won't notice it. The more northward track has always been forecast to occur between 65W and 68W.

Thanks

[wxman57]

http://manati.orbit.nesdis.noaa.gov/sto ... 3_06as.png

One thing to take note of on that image is that TS force winds do not appear to extend more than 100-150 nm to the NW or NE, not hte 300nm the NHC has been carrying. Florence is tightening up a lot now.

[gotoman38]

I have a question, and I think the NHC has been puzzling over the same issue.... Why did Florence resist strengthening for so long?

Shear, temps, pressure.... I may have missed it, but what has been her inhibition?

She (finally!) looks like a strong storm this morning to me.

(And I am also surprised by posters asking about the west run too!)

[Sanibel]

I think 2006 has dry air that isn't being registered.

[Brent]

AT 11 AM AST...1500 UTC...THE GOVERNMENT OF BERMUDA HAS ISSUED A
TROPICAL STORM WARNING FOR BERMUDA. A HURRICANE WATCH AND A
TROPICAL STORM WARNING ARE NOW IN EFFECT FOR BERMUDA. A TROPICAL
STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE EXPECTED
WITHIN THE WARNING AREA WITHIN THE NEXT 24 HOURS. A HURRICANE WATCH
MEANS THAT HURRICANE CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA
...GENERALLY WITHIN 36 HOURS. A HURRICANE WARNING MAY BE REQUIRED
LATER TODAY.

[Mac]

Just because people are concerned about the possibility that this storm could defy atmospheric logic and continue on a more westward track may not necessarily mean that they are wishing it upon themselves.

This is very true. They see it is moving west and just want to know if it will go up the middle and not bother Bermuda that much. I think everyone knows it will not HIT Fla or the whole East coast. Just up the middle. well that is what I have been thinking about any way.

You know, over the past several years of hanging around these boards I have seen numerous storms that did not behave as they were forecast to behave by the pro mets here, by Accuweather, by the NHC, etc. There are storms occasionally that teach us new things about atmospheric synoptics that we did not understand previously. And I have seen the pros saying "this should not happen" or "that should not happen." Then, in retrospect, they sometimes say, "Ahhhhhh, now I understand why that happened. I'm surprised we didn't see it sooner."

Do I think that's going to happen with this storm??? Nope. I think that Wx, Derek, the NHC et al are right on the money with this storm. I always give the pro mets around here a lot of respect. This is their trade, and they've invested years of their lives learning it. I'm just a rookie.

That being said, I always have a little doubt in the back of my mind when it comes to track and intensity forecasts, because I've just seen too many times that sometimes mother nature likes to teach us how little we really know about how she operates. I think she likes to keep us humble.

[wxman57]

I have a question, and I think the NHC has been puzzling over the same issue.... Why did Florence resist strengthening for so long?

Shear, temps, pressure.... I may have missed it, but what has been her inhibition?

She (finally!) looks like a strong storm this morning to me.

(And I am also surprised by posters asking about the west run too!)

In order for a TC to intensify, the air must converge toward a common center, rise up, build storms over the center, and have that rising air properly ventilated away from the storm. Early on, Florence lacked a central focus. There was an area of low pressure 100-150 miles across marking the center. No air was flowing toward the center of that low. Occasionally, we'd see small vortices rotating around inside the larger area of low pressure, but without any air movement toward one of these vortices, they just died out.

On Friday morning, one of these vortices developed and moved northwestward toward an area of building thunderstorms. The small vortex increased convergence into that thunderstorm cluster on the northwest side of the broad area of low pressure. The big low broke down and air flowed toward the developing squalls over the small vortex. That was the start of the strengthening phase.

Why didn't this happen earlier? I think it was a combination of southwesterly wind shear and dry air aloft. Each little vortex rotating around the broad low center could not generate any thunderstorms before yesterday when the shear dropped off.

[Sanibel]

There's band developing on IR.

This is the sign of a gear change and intensification.

[wxman57]

You know, over the past several years of hanging around these boards I have seen numerous storms that did not behave as they were forecast to behave by the pro mets here, by Accuweather, by the NHC, etc. There are storms occasionally that teach us new things about atmospheric synoptics that we did not understand previously. And I have seen the pros saying "this should not happen" or "that should not happen." Then, in retrospect, they sometimes say, "Ahhhhhh, now I understand why that happened. I'm surprised we didn't see it sooner."

Do I think that's going to happen with this storm??? Nope. I think that Wx, Derek, the NHC et al are right on the money with this storm. I always give the pro mets around here a lot of respect. This is their trade, and they've invested years of their lives learning it. I'm just a rookie.

That being said, I always have a little doubt in the back of my mind when it comes to track and intensity forecasts, because I've just seen too many times that sometimes mother nature likes to teach us how little we really know about how she operates. I think she likes to keep us humble.

The hardest storms to forecast are weak depressions/storms. In order to get the track right, you need to correctly forecast the structure/intensity of the developing storm. Weak, sheared storms like Ernesto are extremely difficult to forecast. We just don't have enough atmospheric data to forecast intensity fluctuations, so we can't forecast how the TC will interact with the environment. It's a rare case when we can have anything but very low confidence in the forecast track of a weak system.

Florence, on the other hand, is now a strong TS/hurricane. It's well-established and we have a high confidence that it will only get more powerful with time. That makes the forecast easy when there are well-established steering level winds.

[Mac]

The hardest storms to forecast are weak depressions/storms. In order to get the track right, you need to correctly forecast the structure/intensity of the developing storm. Weak, sheared storms like Ernesto are extremely difficult to forecast. We just don't have enough atmospheric data to forecast intensity fluctuations, so we can't forecast how the TC will interact with the environment. It's a rare case when we can have anything but very low confidence in the forecast track of a weak system.

Florence, on the other hand, is now a strong TS/hurricane. It's well-established and we have a high confidence that it will only get more powerful with time. That makes the forecast easy when there are well-established steering level winds.

I agree that everything seems pretty cut and dry with Flo and, as I said in my previous comments, I think you're right on the money with this storm...and have been from the get-go. But it's not just Ernesto. I've seen numerous other storms over the past few years misbehave and act against presumed synoptics. It's not that I think Flo is going to hit the U.S. I don't. It's just that, having seen previous storms defying logic, I can't help but have this nagging voice in the back of my head that always says "Is this storm going to behave or will it be one of those storms that teaches us new things about atmosopheric synoptics?"

[Thatsmrhurricane]

I don't see anyone talking about it hitting the US . . . Well something about a high over Florida, but the is nothing wrong about talking about why a hurricane does what it does or might do. If I said this will hit Wilmington you can complain. I have noticed amazingly little "wish-casting" with this storm.

8AM 24.4N 63.3W

11AM 24.7N 63.7W

The turn is at the edge of the ridge. The question is where the edge of the ridge was and will anything stop a hurricane, any hurricane not just this one, from the influence of said ridge and front. Also, how well did the models preform compared to reality? I think we found the edge of the ridge. 64W 25N. My question is would a very strong or deep hurricane have turned sooner or later?

[Sanibel]

Well, one answer to that is a very strong hurricane can pump so much subsidence that it enhances the ridge to its north and makes it extend. This shifts the synoptic and creates the illusion of the cyclone "creating its own environment". But even the strongest hurricanes seek the path of least resistance.

[gotoman38]

T-15 and counting for Space Shuttle launch btw