ATL: IRMA - Models

[Hurricane Andrew]

Of note: The GFS 12z initialized noticeably south of the GFS 06z HR6 point. Just food for thought.

[Raebie]

Of note: The GFS 12z initialized noticeably south of the GFS 06z HR6 point. Just food for thought.

Is someone going to post?

[Hurricane Andrew]

Why does the GFS weaken this so much in the next 18 hours?

[Callista]

If we are worrying about Irma making land, shouldn't we be primarily worried about the smaller countries on the way? I know some models have her circling around north of Florida, but it seems to be pointed straight at the Dominican Republic, Haiti, and possibly Cuba.

[Blown Away]

12z GFS slightly SW of 06z through 30 hours...

[pgoss11]

Why does the GFS weaken this so much in the next 18 hours?

Maybe ERC?

[txwatcher91]

Of note: The GFS 12z initialized noticeably south of the GFS 06z HR6 point. Just food for thought.

Very interesting.. My question is why anyone would trust the GFS when it can't even get the track right within 6-12 hours? It has been consistently wrong for days on this, trying to take it much further north than it ends up being. Euro has been doing far better with the track and I can understand exactly why the NHC is weighting their forecast with what it shows vs the further north idea.

[weathaguyry]

36 hours

[robbielyn]

...or maybe the NAO doesnt have as much effect on trough-ridge setups as we thought...

That would be difficult since it's essentially a measurement of pressure differnce at mean sea level between Azores High and Icelandic (also known as sub-polar) Low up that way.

For further verification, we'd have to look out to the WPAC for 7-10 day teleconnections which I haven't done yet but am about to do.

1) TS MAWAR moves NW into China coming up South of Taiwan with anticipated landfall just before 12Z on Sunday. Argues for ridging along the SE US East Coast 10th through 13th, possibly oriented with a NW-SE western periphery

2) Typhoon Sanvu recurves east of Japan on a NNE heading. This argues for troughing just off the US East Coast a bit farther north in the same time frame with probably a subtropical ridge to it's South and East.

^
Mixed signals for next week from the WPAC.

so based off this info, what's ur wild guess as to landfall if any?

[meriland29]

...or maybe the NAO doesnt have as much effect on trough-ridge setups as we thought...

That would be difficult since it's essentially a measurement of pressure differnce at mean sea level between Azores High and Icelandic (also known as sub-polar) Low up that way.

For further verification, we'd have to look out to the WPAC for 7-10 day teleconnections which I haven't done yet but am about to do.

1) TS MAWAR moves NW into China coming up South of Taiwan with anticipated landfall just before 12Z on Sunday. Argues for ridging along the SE US East Coast 10th through 13th, possibly oriented with a NW-SE western periphery

2) Typhoon Sanvu recurves east of Japan on a NNE heading. This argues for troughing just off the US East Coast a bit farther north in the same time frame with probably a subtropical ridge to it's South and East.

^
Mixed signals for next week from the WPAC.

so based off this info, what's ur wild guess as to landfall if any?

We will see, 6z curved out to see, we will see if that will trend or if it was a blip.

[Blown Away]

12z GFS through 42 hours, @40 miles SW of 06z..

[weathaguyry]

42

[weathaguyry]

48

[Ken711]

12z GFS through 42 hours, @40 miles SW of 06z..

I wonder if this is the windshield wiper run with a shift West?

[Blown Away]

12z GFS through 42 hours, @40 miles SW of 06z..

I wonder if this is the windshield wiper run with a shift West?

Long run no idea, but for NE Caribbean these small S adjustments may mean something...

[AutoPenalti]

Notice the trend of "SW by x amount of miles."

Indicating either a increase in forward speed and/or a stronger ridge.

[weathaguyry]

60 hours

[USTropics]

Why does the GFS weaken this so much in the next 18 hours?

There are a few negative factors - an ongoing EWRC that is nearly impossible to model, less than stellar SSTs, and some mid level dry air that is modeled in the GFS.

[weathaguyry]

72 hours

[Steve]

...or maybe the NAO doesnt have as much effect on trough-ridge setups as we thought...

That would be difficult since it's essentially a measurement of pressure differnce at mean sea level between Azores High and Icelandic (also known as sub-polar) Low up that way.

For further verification, we'd have to look out to the WPAC for 7-10 day teleconnections which I haven't done yet but am about to do.

1) TS MAWAR moves NW into China coming up South of Taiwan with anticipated landfall just before 12Z on Sunday. Argues for ridging along the SE US East Coast 10th through 13th, possibly oriented with a NW-SE western periphery

2) Typhoon Sanvu recurves east of Japan on a NNE heading. This argues for troughing just off the US East Coast a bit farther north in the same time frame with probably a subtropical ridge to it's South and East.

^
Mixed signals for next week from the WPAC.

so based off this info, what's ur wild guess as to landfall if any?

Haha. I have no idea. I think the NE Islands have a bit to worry about. Last night I felt like the Bahamian Kingdom has the most to worry about. Bastardi's updated track today shows a Cat 5 just off the NE Tip of Puerto Rico, so the US has major impacts there. Based more or less of the ECMWF, I figured it would go into S FL from the SE or S. But after it swung completely in the other direction, if there's going to be landfall, maybe between North Carolina and Newfoundland? I'd give this about 2% credence from 10 days out. The upper pattern north of 50W has been fluid all season with systems moving west to east across Canada rather than settling into a specific pattern east of 80W.

?