re: Hurricane Irma - Spinning Down

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That good or bad for Louisiana?

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The answer comes later. Still watching it develope.

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I'd argue things look better for the GOM today

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Thanks for the update my guy!

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Probably going to be an annular hurricane
Just means it's round and well defined, right? Doesn't mean it necessarily gets stronger, right?

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Annular hurricanes have better organization and are tighter wrapped. They don't have the far reaching outer bands full of rain but they typically have much stronger winds and they don't weaken as fast over land

Unfortunately trough starts lifting out shortly after the image Duke posted.

what am I missing? I'm not seeing the trough anywhere in play anymore

It's that big blue area of low pressure over the US. Weather works just like water where it flows to the area of least resistance, ie the lower pressure. The red is higher than average atmospheric pressure, or a ridge, that would push the water (read: weather) away.

The blue low pressure trough is sweeping east across the US and is supposed to be right off the east coast about the time Irma is making US landfall. If this trough is still strong enough and unimpeded it'll pull Irma in, ie NE direction. The problem with this is that these patterns are extremely hard to predict, and you also have that area of high pressure pushing Irma SW. The high pressure ridge could completely cut off Irmas path to the trough or push her SW enough to miss it, but it's equally as hard to predict.

Now, here is where it gets tricky. As the models try to resolve that wave break (ridges and troughs rolling against each other basically) what happens in the blue circle. At least on the 00z GFS, there appears to be a bit more ridging across the Gulf. How much energy gets left behind to form the weakness and how fast does Irma feel that and turn north?



ETA: Looks like slightly SW of 18z, so maybe all the extra data didn't make that big of a difference for the landfall area.

Based on the image, GFS is bringing her right up the spine of Florida. It'll take that little gap between the Mx ridge and the big Atlantic one.

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As the models try to resolve that wave break (ridges and troughs rolling against each other basically) what happens in the blue circle. At least on the 00z GFS, there appears to be a bit more ridging across the Gulf. How much energy gets left behind to form the weakness and how fast does Irma feel that and turn north? 

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Good explaination of the remaining difficulties. Subtle differences with big impacts left to resolve.

Looks like this is going to be bad for Anguilla, usvi, bvi, st Bart's, and the northeast carribean. Guessing Luis in 95' was the last direct hit to this area from a major storm?