ATL: MATTHEW - Models

[SouthFLTropics]

HWRF through 24 hours appears to be slightly NE of the 06z position.

[USTropics]

This run of the operational CMC is only good up to 120 hours, and even that is questionable. The suspect storm to the east is not modeled in any of the other operational runs so far, and it significantly alters the western periphery of the CATL ridge. Follow the ensembles on that one.

[CrazyC83]

At this point models generally keeping Matt off the CONUS... Extremely close, but still off the coast... In October, odds are always going to favor E shifts once Matt turns N... Takes perfect scenario to get a CONUS landfall from a system moving from Matt's location...

I think the timing of the incoming trough is more important than the timing of Matthew, although that is important too. In the 12Z GFS, Matthew is just a touch too fast and beats the trough (barely).

[centuryv58]

At this point models generally keeping Matt off the CONUS... Extremely close, but still off the coast... In October, odds are always going to favor E shifts once Matt turns N... Takes perfect scenario to get a CONUS landfall from a system moving from Matt's location...

I think the timing of the incoming trough is more important than the timing of Matthew, although that is important too. In the 12Z GFS, Matthew is just a touch too fast and beats the trough (barely).

Over on the Discussion page, says that this GFS run was a bad initialization so can't trust it.

[gatorcane]

This run of the operational CMC is only good up to 120 hours, and even that is questionable. The suspect storm to the east is not modeled in any of the other operational runs so far, and it significantly alters the western periphery of the CATL ridge. Follow the ensembles on that one.

http://i.imgur.com/eI1KhF5.png

If the CMC doesn't develop that phantom cyclone in the Atlantic to erode the Bermuda high some, one would think it would hit South Florida on this run.

[Hypercane_Kyle]

12z GFS still dramatically different in timing than the ECMWF, which is why the storm ultimately misses the US, bad initialization aside. 12z GFS has the storm north of Cuba by 144 hours, whereas the ECMWF has it south of Jamaica by 144 hours. That's why there's still a risk to Florida and a pretty good one if that were to verify.

[RL3AO]

Over on the Discussion page, says that this GFS run was a bad initialization so can't trust it.

Be careful on the models page. Most pro-mets don't know enough about how models work to make sweeping statements like this, much less amateurs like us.

[HurricaneBelle]

12Z GFS makes ultimate landfall over northern Nova Scotia/New Brunswick, which would bring some nasty weather to our friends in the Canadian maritimes.

[terstorm1012]

the east turn of the Canadian away from the US is bull you know what

It has a phantom TC to the east that creates a weakness

might be the wave at 40W?, there's a pouch for it

[chaser1]

I believe the east shifts for the GFS are just beginning. A few more runs like this trend from the 12z GFS and the system may only threaten Canada or go OTS. It will be interesting to see what the ECMWF does at 1:45EST.

See here:
http://www.tropicaltidbits.com/analysis/models/?model=gfs&region=atl&pkg=z500a&runtime=2016092812&fh=192&xpos=0&ypos=200

The majority of the "rightward shift" was due to the incorrect initialization playing out downstream in the model. It is not a true shift.

I'll admit that I may be very well wrong here but I believe that the solution that the GFS is wrong but far less having to do with its initialization. Keep this in mind, the GFS has been steadfast to forecast Matthew to make a sharp right turn and exit the Caribbean in a nearer time frame. Meanwhile the EURO has lagged in time, and with recent runs even trended further west. This all seems to indicate how the various models are handling the ridge to the north. The GFS is insistent that the cut-off low (presently seen on water vapor satellite) will play a significant role in degrading the ridge to the north of Matthew. What further influence Pouch 41 may or may not have remains to be seen. The cut-off low however, seems to be WAY WAY east of the picture while a developing Matthew is spewing some pretty heavy outflow into the upper atmosphere that would seem to help pump up the ridge to its north. I'm simply guessing that the EURO (and a couple other models now) are better handling this complex interaction. Its this reason that I'd even expect the EURO to show a track that might move Matthew further west than its last run, and I"m beginning to think that Matthew will pass just to the west of Jamaica. Downstream ramifications would be huge if this were to verify, but for the sake of this discussion believe why there would appear to be an increasing discrepancy between the GFS and other models. I'll guess that later on today we'll see that a few GFS members might well lean toward a more gradual NW motion, while obviously the larger concentration of them must be spread a good deal more to the north indicative of the operational model depicted forecast.

[centuryv58]

Over on the Discussion page, says that this GFS run was a bad initialization so can't trust it.

Be careful on the models page. Most pro-mets don't know enough about how models work to make sweeping statements like this, much less amateurs like us.

I"ll let you pass that one along to them!

[USTropics]

the east turn of the Canadian away from the US is bull you know what

It has a phantom TC to the east that creates a weakness

might be the wave at 40W?, there's a pouch for it

It's the remains of the two vorticities that spawned when this wave left Africa, P39L.

[Hurricaneman]

I'm more likely to go with a creeping movement to the NW after 4 days due to steering breaking down and changing which would go hand in hand with the Euro solution but would also put Florida at enhanced risk but as that cars salesman on Family matters said "Its not written in stone, its written in shoe polish"

[Nimbus]

Seeing these potential storm tracks with ridging intact is pretty frightening.
That big low currently over the Great Lakes has been throwing some digging troughs that roll off the East coast. Really impossible to predict an exact trough timing but for those that use the water vapor imagery there is still hope IF that big ULL doesn't lift out.

[chris_fit]

Who's making popcorn for the 12Z Euro? Up within the hour

[WeatherEmperor]

Who has the 12z Navgem??


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[SouthFLTropics]

HWRF has a 1 degree SW dive in latitude between hours 33 and 54. That's pretty pronounced for just over 20 hours. Matthew looks like its riding the Eastern Caribbean roller coaster on this run. Up and Down, Up and Down.

[SouthFLTropics]

HWRF still ends up being farther NE at hour 78 by almost 1 square of latitude and longitude. Looks stronger as well.

[chaser1]

Again, not to split hairs but does the GEM also seem to initialize Matthew about 75 miles to far north? Shouldn't have anything to do with how the model forecasts synoptic changes, just something to possibly account or adjust for downstream perhaps.

[SouthFLTropics]

JMA through 72 hours is much further west than yesterday's run. However, it doesn't appear to have the current strength right. Shows it relatively weak until clearing South America.