ATL: IAN - Models

[SFLcane]

 https://twitter.com/andyhazelton/status/1574085007722831888

[gatorcane]

Almost a 1 degree shift east on the HWRF at 63 hours. Slower also.

[SapphireSea]

Not until I see the Euro start trending to the left towards the official track will I say that the NHC track is good in the 3-5 day range.

I admire the loyalty of the NHC to the GFS, but at some.point you have to pay serious attention to the rock solid Euro. Euro has seemingly been locked on for several days now, while GFS has been on a grand tour of the gulf coast. It looks today like the GFS is starting to fold to the Euro solution, which we have seen happen before as we get into the 3 to 5 day range. I think the NHC will have to shift the track east now, even if they expand the cone to take the gfs swings into consideration. Bottom line is, over 2/3 of the gulf coast of Florida, as well as Alabama and Mississippi better be watching closely and ready to act fast.

The cone never changes in size during the year, it's a simple calculated error circle around a forecast point. You make a couple of false statements here so please don't assume you understand how their forecasting works. The technique they use has been responsible for steadily increasing accuracy. Sometimes it doesn't work out, but right now the storm isn't even a hurricane yet so I think it might be a little soon to jump the gun.

This is 100% true. To add a little color; The cone is a static metric made up of previous errors observed by NHC. I believe this is built from the last-5 years of analysis, so it's possible for future cones to change, but not from storm-to-storm. The situation we see with the models is why the NHC forecast can sometimes be an outlier from modeling, because the models are a supplement not the only basis for their forecast; And humans are better equipped for now to make the correct adjustments given the realities that evolve in real time.

That said: This is a tricky forecast. The trough is strong, and is not an extreme anomaly for this time of year, so its hard to discount E solutions. In fact personally I still believe that this is probably too far W, but there are extremely valid determinations in all models for why they handle things. Save for a few GFS runs ago that had the storm intensifying after crossing a frontal boundary and completely unmoved by the W-E flow that would be present with such an active front. The newer runs showing slight NE bends and rapid weakening are more realistic now, and it's becoming increasingly tougher to dismiss the GFS; Making this a tough forecast.

NHC is really showing their stuff right now, and I fully expect them to be well within historical errors (cone) in reality. If you plug in the track on old cones from days ago, we'll see that the storm isn't entirely out of forecast in the long-run. And even in short-term it's out maybe by a few miles due to reformations and disorganization.

[Poonwalker]

Consider Cuba the launching point for this system. The steering dynamics are well established and the GFS and Euro are now operating with a similar trough setup. They also and have the support of weather balloons going up in WA every 6 hrs.

[Blown Away]

If a track towards Big Bend is likely the Euro should start trending a little west towards GFS. If Euro trends more SE then landfall S of Tampa becoming an option.

[tolakram]

[SFLcane]

If a track towards Big Bend is likely the Euro should start trending a little west towards GFS. If Euro trends more SE then landfall S of Tampa becoming an option.

Could be but as yet I have not seen any substantial trend towards the NE we’re it would give Southern Florida anything more then some rainy days.
,

[LarryWx]

https://i.imgur.com/NtQeWBN.png

This 24 hour 12Z Euro position appears to be a little south of the 6Z Euro 30.

[tolakram]

[tolakram]

Very close to the same spot as 6Z.

[toad strangler]

 http://twitter.com/TropicalTidbits/status/1574096719620739072

[SFLcane]

12z ukmet pretty far south.

[chris_fit]

12Z EURO So Far...

[gatorcane]

At 48 hours the Euro looks to have slightly less ridging to the east of Florida than the 06Z.

[Blown Away]

12z GFS/Euro basically same spot at 48 hrs. This is where the spread has begun in previous runs.

[tolakram]

trend

[tolakram]

[skillz305]

At 48 hours the Euro looks to have slightly less ridging to the east of Florida than the 06Z.

Slightly less ridging on the east of Florida, would result in?

[tolakram]

EC-FAST does not have a 10m plot, this is 850mb

[Blown Away]

12z Euro starts NE turn from 60-66 hrs