ATL: DORIAN - Post-Tropical - Discussion

[Nimbus]

The Virgin islands will be in the northeast quadrant with the heaviest winds.
Must be making a westward wobble because the track looks uncomfortably close to San Juan.
Usually not a good idea to try and micro forecast but it would be nice if San Juan ended up on the west side of the eventual track.

GFS has landfall in South Carolina so the confidence level is still low for the Florida forecast.
The LLC of Erin hasn't decoupled from the mid level circulation yet so that might delay Dorians turn back toward the west.

[AdamFirst]

From discussion

Fixes from the reconnaissance plane indicate that Dorian has been
moving toward the northwest or 315 degrees at 11 kt. The cyclone is
heading toward a weakness in the Atlantic subtropical ridge, and
this motion should continue for the next 2 to 3 days. However, after
that time, all global models build a robust ridge over the western
Atlantic, and this flow pattern should force Dorian to turn more
to the west-northwest toward Florida and the southeast coast of the
United States. All indications are that by this Labor Day weekend, a
powerful hurricane will be near the Florida or southeastern coast of
the United States. The new NHC track forecast is not significantly
different from the previous one, and it very closely follows the
multi-model consensus TVCA and the HCCA. Users are reminded not to
focus on the exact forecast track, as the average 5-day track error
is around 200 miles.

[GCANE]

Could get a visible eye before sunset.

[USTropics]

Definitely an eyewall feature showing up on radar, roughly outlined below with current radar motion extrapolated:

[ouragans]

When my trainer says this, I have to believe him

 https://twitter.com/EricBlake12/status/1166728734939893761

[jlauderdal]

Wouldn’t a deeper more intense hurricane end up further south into Florida?

why is that? poleward movement to the north as intensity increases, not always though

[marionstorm]

Can someone let me know if this is going to be worse than Irma for Marion County? : (

Seeing that M on the map makes me very anxious.

[chris_fit]

You're welcome NHC - I'll send you the bill

[jdjaguar]

Dorian will be a very tiny hurricane starting to slow down.

I do not see how you can validate your statement that Dorian will be a "very tiny" hurricane when it strengthens to CAT3+ in the bahamian bathtub.

[Aric Dunn]

Geez i step away for a couple hours too actually be productive at work and its passing by st croix already.. sheesh.

[USTropics]

Large blow up of convection along 2/3 of the eyewall, when this rotates around it'll have a prime opportunity to close off. That will most likely be the final step for allowing Dorian to reach Hurricane strength:

[mpic]

So am I reading correctly that Puerto Rico might be spared a direct hit?

[GCANE]

This blow up of the towers firing off and rotating around the eye definitely increases chances of RI by an order of magnitude.
They are quickly heating the core from latent heat release.
Should see large pressure drop in a couple hours and subsequent pickup in wind speed.
No doubt a Cat 1 later this afternoon.

[Steve]

Can someone let me know if this is going to be worse than Irma for Marion County? : (

Seeing that M on the map makes me very anxious.

Nobody can tell you that. Prepare like it will be and make sure you have everything you need. Rush will be on by tomorrow.

[Aric Dunn]

And an eye is showing on satellite.. what did you all do lol


Outflow is still great.. too

[MississippiWx]

As many have alluded to already, the new blow-up of convection over the eye wall is a big step in the strengthening phase. Watch to see when/if it completely wraps around the entire center. When it does, rapid intensification is likely. The eastward adjustments in the track have mostly protected Dorian from high shear. Not good.

[chris_fit]

So am I reading correctly that Puerto Rico might be spared a direct hit?

Not a pro, but I don't see how it can landfall there as of now...

[USTropics]

Dorian will be a very tiny hurricane starting to slow down.

I do not see how you can validate your statement that Dorian will be a "very tiny" hurricane when it strengthens to CAT3+ in the bahamian bathtub.

Dorian will expand, the cycle of tropical systems requires it. Typically we see a tropical system hit a threshold for its current structure, and it must expand its wind field in response to lowering pressures in order to further strengthen. This is one of the reasons we see EWRCs.

[Aric Dunn]

As many have alluded to already, the new blow-up of convection over the eye wall is a big step in the strengthening phase. Watch to see when/if it completely wraps around the entire center. When it does, rapid intensification is likely. The eastward adjustments in the track have mostly protected Dorian from high shear. Not good.

Yeah RI is a big possibility in the next 24 hrs.
The upper low is weaker and moving west, out of the way. Expect further south adjustments to models now that this farther east of track..

[Aric Dunn]

Also looks like it might be the highest pressure hurricane soon.