Storm will turn NW: NHC 8PM Discussion

[calidoug]

Storm already encountering weak trough to the W, will use this weakness to move poleward, as *even stronger trough* moves into SE US from the W...

http://www.nhc.noaa.gov/text/MIATWDAT.shtml

[ColdFront77]

Interesting. I have been hearing that this trough is weak (also have obserbed) that this trough is weak and was going to dissipating over the southeast.

[southerngale]

Just curious...calidoug, where did you hear strong trough and Tom, where did you hear weak trough?

I'm just wondering if it's supposed to be strong or weak.

[ColdFront77]

Kelly, The Tropical Prediction Center/National Hurricane Center mentions that the trough is strong (see above line) in their Tropical Weather Discussion from 8:05 PM Eastern.

The National Weather Service in Melbourne, FL indicated that the cold front was slowing down from its already slow speed and expected to dissipate over north Florida. They said this a few days ago (honestly not sure about now), however you can see the frontal system meandering without much precipitation along it.

[vbhoutex]

The strong trough they are mentioning is the second one coming in, not the one that is already E of us here Kelly. We will be getting the stronger one today(monday)if it isn't already past us(I need to take a look at WV I guess.) It will be close enough to the E coast Tuesday to begin pickng up Isabel and nudging her into that turn unless some really unexpected weakening occurs. The discussion of the ridge continuing W with Isabel is disturbing till you begin to realize she will be caught in a squeeze play between the two. I am not yet convinced the landfall will be as far north as currently predicted, but I am keeping an open mind about it. And as I've stated before about Isabel and others-NEVER SAY NEVER-especially this season. She has been defying the odds all along IMO, Hopefully she has no more surprises up her sleeve except a sharp right turn out to sea!!! HOW WE ALL WISH!!!!!

[southerngale]

Thanks for the great explanation David...very helpful.

Tom, so are you saying the trough that David is calling strong is expected to dissipate over Florida and not pick up Isabel? I may be wrong...I'm just trying to understand what you mean.

[ColdFront77]

The strong trough they are mentioning is the second one coming in, not the one that is already E of us here Kelly. We will be getting the stronger one today(monday)if it isn't already past us(I need to take a look at WV I guess.) It will be close enough to the E coast Tuesday to begin pickng up Isabel and nudging her into that turn unless some really unexpected weakening occurs. The discussion of the ridge continuing W with Isabel is disturbing till you begin to realize she will be caught in a squeeze play between the two. I am not yet convinced the landfall will be as far north as currently predicted, but I am keeping an open mind about it. And as I've stated before about Isabel and others-NEVER SAY NEVER-especially this season. She has been defying the odds all along IMO, Hopefully she has no more surprises up her sleeve except a sharp right turn out to sea!!! HOW WE ALL WISH!!!!!

I can see why the strong trought that is being mentioned is the second one coming in, not the one already approaching the east coast. With that said... it goes to show that the one further behind is quite a bit further to pick up Isabel and move her northward. In the meantime, the ridge to the storms northeast could easily make it's way southwestward.

Thanks for the great explanation David...very helpful.

Tom, so are you saying the trough that David is calling strong is expected to dissipate over Florida and not pick up Isabel? I may be wrong...I'm just trying to understand what you mean.

The trough I was talking about is the one across the eastern U.S. right now (and you can see my reponse to David above)