ATL: HERMINE - Post-Tropical - Discussion

[Aric Dunn]

pressure 1008 this pass.

[Sanibel]

The Gulf often has a sacrifice storm that clears it out for those that follow...

[Aric Dunn]

I love fluids.. the circ is already "feeling" the open waters of the channel. the wind field from recon is so great. I bet the center jumps to the west over the next few hours in or very near the channel now thats something you dont see in a lot of models.. . long story short following the path of least resistance.

[Chris_in_Tampa]

Through 3:48am EDT:

[Aric Dunn]

oddly pressure falling with no convection..over all lift in the column ? large convective burst coming soon ?

[Aric Dunn]

pretty crazy development there.. for the people interested in the actual dynamics..

[Blinhart]

So all the models are not initializing at the right spot, it should be further SW.

[Aric Dunn]

So all the models are not initializing at the right spot, it should be further SW.

the center per recon has moved more wsw .. but I was just mentioning some minor dynamical details( which could play a bigger role) but for me are exciting from a science point of view.

[Aric Dunn]

Also the circ is now west of the shear axis should see some significant organization today.

[mobilebay]

So all the models are not initializing at the right spot, it should be further SW.

the center per recon has moved more wsw .. but I was just mentioning some minor dynamical details( which could play a bigger role) but for me are exciting from a science point of view.

I've noticed, from recon fixes that it is at 83.9 west, it wasn't supposed to be there until 12 hours according to nhc forecast at 03Z

[Aric Dunn]

Also yes its the NAM.. but it really slowed down ( from the 00z i mean a lot) environment has become much better this run and its starting to bomb out.. the nam for synoptic is worth listening to..

[Aric Dunn]

looks to be moving into a extremely divergent upper environment since it has taken such a wsw track. upper ridging building over it. could see significant convection over the next few hours.

[johngaltfla]

looks to be moving into a extremely divergent upper environment since it has taken such a wsw track. upper ridging building over it. could see significant convection over the next few hours.

Which is really bad news for anyone on the West Coast of Florida..everyone from Naples to Pensacola had best pay strict attention to this storm because now it can strut. It's in the proverbial match meet gasoline zone for storm intensification today.

[GCANE]

Looks like it is fighting an infeed of mid-level dry air coming from FL.
The pop-up afternoon thunderstorms over the Glades weren't as strong as I thought would be yesterday and they didn't help to moisten the mid-levels.
Also, vort is a little too close to Cuba and it can't get any WISHE air from water on its southern flank.
Core looks to have cooled off as well, no signature of a positive temperature anomaly at 10km.
Its tracking into lower CAPE and Theta-e levels as well.
MIMIC-TPW does show good moisture surrounding this.
So, it looks like IMHO that it needs to get out more in the open waters to reorganize.
I am still watching if pop-up, afternoon thunderstorms develop over FL which would take out the mid-level dry-air infeed to TD9.

[arlwx]

TROPICAL DEPRESSION NINE ADVISORY NUMBER 3
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092016
500 AM EDT MON AUG 29 2016

...POORLY ORGANZIED DEPRESSION MOVING INTO THE EXTREME SOUTHEASTERN
GULF OF MEXICO...


SUMMARY OF 500 AM EDT...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...23.5N 83.9W
ABOUT 155 MI...245 KM WSW OF KEY WEST FLORIDA
ABOUT 95 MI...155 KM WNW OF HAVANA CUBA
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...W OR 275 DEGREES AT 9 MPH...15 KM/H
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 500 AM EDT (0900 UTC), the center of Tropical Depression Nine was
located near latitude 23.5 North, longitude 83.9 West. The
depression is moving toward the west near 9 mph (15 km/h). A turn
toward the west-northwest is forecast today, followed by a
slow northwestward motion on Tuesday. On the forecast track, the
center of the depression will be passing north of the north coast
of western Cuba today, and moving farther into the southeastern Gulf
of Mexico by tonight.

Data from a NOAA reconnaissance aircraft indiate that the maximum
sustained winds are near 35 mph (55 km/h) with higher gusts. Some
strengthening is forecast during the next 48 hours, and the
depression could become a tropical storm later today or tonight.

The estimated minimum central pressure is 1007 mb (29.74 inches).


HAZARDS AFFECTING LAND
----------------------
RAINFALL: The depression is expected to produce total rain
accumulations of 3 to 5 inches over the southern Florida peninsula
and the Florida Keys through Wednesday. Isolated maximum
amounts of 7 inches are possible over coastal areas of southern
Florida and the Keys. This rainfall may cause flooding and flash
flooding.

[GCANE]

The ULL off Savanaha is going to be a mixed bag for TD9.
On one hand, it will feed in mid-level dry air into TD9,
On the other hand, it induces shear over FL which helps to generate overland thunderstorms which in turn moisten the mid-levels.
IMHO, if or when convection really fires up in the form of some solid hot towers, they will push out any weak to moderate shear.
Gotta respect the loop current.

[Chris_in_Tampa]

Through 5:18am EDT:

[Nimbus]

Even though the convection is sheared south over Cuba recon found a 1007 MB surface pressure so I guess it maintained over night. Lets see how long it takes to drop down to 1005 once it starts to clear Cuba. These 6 hourly flights should be a real help for the models.

[Orlando]

Brian Shields at WTVF Orlando just said (at 5:50 AM),"no need to freak out." He also said that heavier rain from this storm will come Wednesday and Thursday--about a 70% chance of rain and possibly into Friday depending on the track. He said there will be a chance of mild tornadoes. He also said that the storm is very disorganized and their was about a 40% chance of Orlando getting tropical weather from it.

[HurriGuy]

This looks like it is really going to pop this morning