ATL: ISAAC - Models

[Janie2006]

I'm really waiting to see what the Euro does, personally.

[SunnyThoughts]

It's beginning to slow down and the center is starting to relocate to the north. Jmo though

Even if that is the case, the model doesn't know that, the 0z models are probably about completed..we just don't see them until later. Anything that happens now probably wouldn't show up in the models until tomorrow. If what others have said in here is factual.

Hey Sunny, I thought the models started running at specific times automatically, so I don't think they have been completed yet. (I am not sure about this, so someone please correct me if I am wrong!) One of the METS explained the models last night, saying that the data goes into them automatically (no one actually sits down and enters it), and they initialize.. Sooo, the 00z models may have the current data in them..

smw, yeah they said the info goes into the models automatically...but not at the time we actually SEE the outcome. I think whomever it was said it has to go through quite a bit in discarding old data and new data being incorporated. What I was trying to say was that, by the time we actually see what the model runs are..the info has been processed a couple hours in advance. I could have very well misunderstood, but that is the way I remember it.

[Ivanhater]

Not sure if the overnight models will show the center relocation that looks to be taking place right now...but I think we are done seeing any westward movement in the models and will start inching eastward again. We will find out

[deltadog03]

Not sure if the overnight models will show the center relocation that looks to be taking place right now...but I think we are done seeing any westward movement in the models and will start inching eastward again. We will find out

AGreed!! I think the west shift is over....We shall see tonight.

[bonjourno]

NAM at 57 hours looks exactly on the AL/FL border.

[theavocado]

This post does a great job in showing how "interpolated runs" can be misleading. With the wobble of Isaac, the storm moved more westward than the forecast track had shown. When the later models were dropped on the new position, it looks as if the models have shifted west, but in actuality, the models tracks that are shown are 6 hours old and retooled to fit the current position. They are more or less shifted over with 6 hours lobbed off (well, there is more to it, but I'm simplifying). The whole track gets shifted in this case. So, if the steering level of the ridge to the east would put the storm at the LA/MS line, this would be lost in an interpolation that is the result of an unforecasted wobble.

Timestamps of the maps are in the lower left corner

http://i.imgur.com/eyg7i.gif


http://i.imgur.com/qEzF8.gif

*edited by southerngale to remove the IMG tags from quote

[SunnyThoughts]

Well I guess we will see Ivan, I sure hope they get it worked out soon...My nerves can't take much more lol. Actually, we are very well prepared for whatever...its just the not knowing for sure what we have to deal with yet that is so bad.

[sphelps8681]

Not sure if the overnight models will show the center relocation that looks to be taking place right now...but I think we are done seeing any westward movement in the models and will start inching eastward again. We will find out

AGreed!! I think the west shift is over....We shall see tonight.

Completely a novice on all this. Please explain why you feel that way.

[N2FSU]

00Z NAM: 60hr

Looks like due North or slight NNE movement last 2 frames... feeling the weakness

[BigB0882]

I also have this feeling (nothing more) that the models will begin inching Eastward as well but not by big amounts at all. The only one I think is coming West is the Euro which will finally meet the GFS somewhere in the middle.

[smw1981]

Hey Sunny, I thought the models started running at specific times automatically, so I don't think they have been completed yet. (I am not sure about this, so someone please correct me if I am wrong!) One of the METS explained the models last night, saying that the data goes into them automatically (no one actually sits down and enters it), and they initialize.. Sooo, the 00z models may have the current data in them..

smw, yeah they said the info goes into the models automatically...but not at the time we actually SEE the outcome. I think whomever it was said it has to go through quite a bit in discarding old data and new data being incorporated. What I was trying to say was that, by the time we actually see what the model runs are..the info has been processed a couple hours in advance. I could have very well misunderstood, but that is the way I remember it.

Oh yeah..I think he said an 1-1.5 hours because it seems like he said that once we see the output of a model, it has really already been running about an hour. However, (as you know!) it was super late (maybe 1am?), so I may have completely misunderstood! ha

[HurrMark]

00Z NAM: 60hr

Looks like due North or slight NNE movement last 2 frames... feeling the weakness

Interesting...actually making landfall in good ol' F-L-A. It's only a 30 mile shift and may be splitting hairs, though. Let's see if it turns back towards the west.

[bella_may]

This post does a great job in showing how "interpolated runs" can be misleading. With the wobble of Isaac, the storm moved more westward than the forecast track had shown. When the later models were dropped on the new position, it looks as if the models have shifted west, but in actuality, the models tracks that are shown are 6 hours old and retooled to fit the current position. They are more or less shifted over with 6 hours lobbed off (well, there is more to it, but I'm simplifying). The whole track gets shifted in this case. So, if the steering level of the ridge to the east would put the storm at the LA/MS line, this would be lost in an interpolation that is the result of an unforecasted wobble.

Timestamps of the maps are in the lower left corner

http://i.imgur.com/eyg7i.gif


http://i.imgur.com/qEzF8.gif

also keep in mind that most of the models going to texas are the bamm

*edited by southerngale to remove the IMG tags from quote

[bonjourno]

I know it's just a little nitpick of a not-so-great model to begin with....but the NAM between landfall at 57-60 hours and 69 hours seems to definitely nudge the storm nearly due east along the FL panhandle.

The center doesn't look like it moves all that much, but if you compare the 1008 and 1010 isobars on the east side of it, they definitely moved a good 50 miles.

[PTrackerLA]

I remember when Gustav had a center relocation near Jamaica the track/models literally didn't budge. We'll see in the AM I guess.

[theavocado]

also keep in mind that most of the models going to texas are the bamm

I like to refer to the BAMS as "models" and not models. But, there is a shift in the skilled numerical models too.

[HurrMark]

Unlike the 12Z run, where it backs west into AL-MS-LA, the 00Z run kinda just sits in the NW panhandle but doesn't really get "caught". Interesting...

[PTPatrick]

New Canadian showing Pascagoula according to that time stamp

[N2FSU]

00Z NAM: 72hr

Barely moves once it makes landfall.

[timNms]

Not sure if the overnight models will show the center relocation that looks to be taking place right now...but I think we are done seeing any westward movement in the models and will start inching eastward again. We will find out

AGreed!! I think the west shift is over....We shall see tonight.

I'm in agreement with both of you. I've been watching this thing closely all day and looking at wv loops of the US. I think the NHC's track is pretty close to where this thing will end up.

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