ATL: JULIA - Post-Tropical - Discussion

[Hammy]

Original vortex (east one) appears to be dissipating. Now there's another one to the north and one to the south. I don't buy those SFMR reports from the plane. 20-25kt FL winds and 35-38kt SFMR???

Hasn't that happened before with tilted systems?

[xironman]

It will be fun to see how the NHC deals with the SFMR, it is not just one aberrant reading, the whole NE quadrant is showing close to TS winds. Maybe "broken sensor"?

[Emmett_Brown]

So, would the models show a different outcome if they are initialized with a 1007mb pressure?

[Hammy]

It will be fun to see how the NHC deals with the SFMR, it is not just one aberrant reading, the whole NE quadrant is showing close to TS winds. Maybe "broken sensor"?

18Z has 35kts so upgraded back to a tropical storm at 5pm by the looks of it--it's entirely possible it never weakened to a TD in the first place as there was little data gathered over the last day.

[Kazmit]

What's ironic about this storm is that it strengthened to a tropical storm over land, and then weakened as soon as it emerged back onto water. Simply remarkable.

[Fishing]

It will be fun to see how the NHC deals with the SFMR, it is not just one aberrant reading, the whole NE quadrant is showing close to TS winds. Maybe "broken sensor"?

18Z has 35kts so upgraded back to a tropical storm at 5pm by the looks of it--it's entirely possible it never weakened to a TD in the first place as there was little data gathered over the last day.

What is her movement? Still heading off to the East or is she stationary now?
And as an edit the skies just went dark and we have downpours again. Go figure.

[LarryWx]

She looks to me per visible loops like her initial center has degraded and that she may have a MUCH broader center that is elongated SW to NE taking over. Not healthy looking to me as shear is doing a number on her.
If she survives this reorgnization of sorts, she may be repositioning slightly further west than where that original center degenerated, which was near 77.4W, with little or no more eastward movement.

[JaxGator]

What's ironic about this storm is that it strengthened to a tropical storm over land, and then weakened as soon as it emerged back onto water. Simply remarkable.

Yeah, that is weird but we have swamp land and it did use energy from the ocean/Gulf Stream, so it's not impossible but rare.

[cycloneye]

TROPICAL STORM JULIA DISCUSSION NUMBER 8
NWS NATIONAL HURRICANE CENTER MIAMI FL AL112016
500 PM EDT THU SEP 15 2016

An Air Force Reserve Hurricane Hunter aircraft investigated Julia
and reported estimated surface winds of 35-40 kt from the SFMR
instrument in the northeast quadrant, along with a central pressure
of 1007 mb. The maximum flight-level winds at 850 mb were 34 kt.
Based on a blend of the surface estimates and flight-level winds,
the initial intensity is increased to 35 kt. The aircraft reported a
sharp trough extending to the east of the center, and the storm is
producing vigorous convective bursts near the center and along the
trough.

Julia continues to move generally eastward or 085/7, possibly due
to the reformation of the center caused by the convective bursts.
The track guidance continues to forecast that the cyclone will slow
its forward motion in the next 12 hours, after which it will move
very little through 72-96 hours. Based on this premise, which so
far has not come to pass, the new forecast track will keep Julia
moving east for 12 hours and then show a loop from 12-96 hours. The
new forecast area of meandering is about 60 n mi east of that from
the previous forecast.

Julia is likely to experience very strong westerly to northwesterly
shear from 12-84 hours, and this is expected to cause a gradual
weakening during this time. The NHC intensity forecast follows the
previous one in calling for the cyclone to degenerate to a remnant
low by 72 hours and dissipate completely by 120 hours. If Julia
survives the extended period of shear, the environment should become
more favorable after 84 hours, and the system could re-intensify as
forecast by the UKMET and Canadian models.


FORECAST POSITIONS AND MAX WINDS

INIT 15/2100Z 32.1N 77.1W 35 KT 40 MPH
12H 16/0600Z 32.0N 76.6W 35 KT 40 MPH
24H 16/1800Z 31.8N 76.4W 30 KT 35 MPH
36H 17/0600Z 31.5N 76.4W 30 KT 35 MPH
48H 17/1800Z 31.5N 76.7W 30 KT 35 MPH
72H 18/1800Z 32.0N 77.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
96H 19/1800Z 32.5N 76.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 20/1800Z...DISSIPATED

$$
Forecaster Beven

[cycloneye]

...HURRICANE HUNTER AIRCRAFT FINDS THAT JULIA IS AGAIN A TROPICAL
STORM...
...EXPECTED TO MEANDER OFF THE COAST OF SOUTH AND NORTH CAROLINA FOR
THE NEXT FEW DAYS...


SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...32.1N 77.1W
ABOUT 175 MI...285 KM ESE OF CHARLESTON SOUTH CAROLINA
ABOUT 150 MI...245 KM SSE OF WILMINGTON NORTH CAROLINA
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...E OR 85 DEGREES AT 8 MPH...13 KM/H
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES

[tolakram]

Visible. If you speed it up it appears the center has stayed mainly intact but relocated closer tot the convection.

http://weather.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20CONUS&lat=32&lon=-80&info=vis&zoom=1&width=1000&height=800&quality=90&type=Animation&palette=ir1.pal&numframes=30&mapcolor=yellow

[LarryWx]

The latest visible pics suggest that the old center is actually hanging on with very little movement. I had thought it was degrading. I have it near 32.2N, 77.2W.

Lol, I got ninjaed.
-------------------------------------------
Based on the 5:15 PM EDT visible pic, the center is no longer moving eastward and is about stationary near 32.0N, 77.3W. Where will she go from here?

[wxman57]

The latest visible pics suggest that the old center is actually hanging on with very little movement. I had thought it was degrading. I have it near 32.2N, 77.2W.

Lol, I got ninjaed.

I see the same thing, Larry. It's stalled again and the "old center" which threatened to dissipate has once again become the dominant vortex. I think it'll gradually weaken and become a remnant low over the weekend, though. Probably not a heavy rain threat to the Carolinas.

[JaxGator]

The latest visible pics suggest that the old center is actually hanging on with very little movement. I had thought it was degrading. I have it near 32.2N, 77.2W.

Lol, I got ninjaed.
-------------------------------------------
Based on the 5:15 PM EDT visible pic, the center is no longer moving eastward and is about stationary near 32.0N, 77.3W. Where will she go from here?

That was weird seeing the two centers earlier but now it's one again. If shear keeps up the tempo then Julia might slowly die but if it comes back to the coast, then it may bring some rain with it (but that's doubtful right now). Not a forecast. You've done a good job on keeping tabs with the cyclone btw. Even in its beginning.

[LarryWx]

The latest visible pics suggest that the old center is actually hanging on with very little movement. I had thought it was degrading. I have it near 32.2N, 77.2W.

Lol, I got ninjaed.
-------------------------------------------
Based on the 5:15 PM EDT visible pic, the center is no longer moving eastward and is about stationary near 32.0N, 77.3W. Where will she go from here?

That was weird seeing the two centers earlier but now it's one again. If shear keeps up the tempo then Julia might slowly die but if it comes back to the coast, then it bring some rain with it (but that's doubtful right now). Not a forecast. You've done a good job on keeping tabs with the cyclone btw. Even in its beginning.

Thanks. What may be the last vis pic of the day (6:45 PM EDT) shows it moved back south over the last hour or so to near 31.8N, 77.3W. It also shows that the strong shear caused the western extent of the convection that was barely east of the center recently to move eastward further east of the center.

[wxman57]

Looks like shear is beatin' the crap out of it again (sorry for the technical meteorological jargon). The LLC is now drifting slightly west of south while the convection is ripped away. It will continue to struggle with shear until it fades away.

[LarryWx]

Looks like shear is beatin' the crap out of it again (sorry for the technical meteorological jargon). The LLC is now drifting slightly west of south while the convection is ripped away. It will continue to struggle with shear until it fades away.

57,What if she were to move south enough (like say to 30-30.5N)? Would that put her in lighter shear for the next few days? The GFS sure does suggest that to me before stronger shear comes down late Monday, but who knows if that is even accurate?

Update for 7:45 PM EDT sat. pic: Center moving SSW and now down to near 31.6N, 77.5W. The 5 PM NHC track doesn't it have it that far south for another 24 hours as they have it still moving slowly eastward instead of SSW. The naked swirl can still be clearly seen on IR.

Interestingly, I'm getting a shower within a band that is moving SW around the backside of Julia. This is the only rain of the day.

[cycloneye]

TROPICAL STORM JULIA DISCUSSION NUMBER 9
NWS NATIONAL HURRICANE CENTER MIAMI FL AL112016
1100 PM EDT THU SEP 15 2016

Just like it occurred last night, a surge of strong upper-level
westerly winds removed the convection from the center of Julia again
tonight. Satellite images show that the circulation is still
vigorous, and it is generously assumed that tropical-storm-force
winds are occuring well to the east of the center. On this basis,
the initial intensity is kept at 35 kt. The strong shear is forecast
to persist, and the most likely solution is for Julia to maintain
the same intensity for another 12 hours or so, and then gradually
decay as indicated in the previous NHC forecast. It is worth noting
that the SHIPS and LGEM models maintain Julia as tropical storm for
the next 3 days, but the given the strong shear predicted by these
models, their solution does not appear to be realistic.

The tight swirl of low clouds defining the center of Julia has been
moving slowly toward the east-southeast or 120 degrees at 4 kt.
However, the steering currents are expected to be weak, and the NHC
forecast calls for Julia to meander during the next 2 to 3 days. By
then, Julia is expected to be a remnant low, and probably will
begin to drift northeastward, embedded within the mid-latitude flow.
Since the steering currents are likely to be weak and poorly
defined, the track models are showing divergent solutions, varying
from northeast to southwest tracks, and some show no motion at all.
The discrepancy in the models increases the uncertainty of the NHC
track forecast.


FORECAST POSITIONS AND MAX WINDS

INIT 16/0300Z 31.5N 77.1W 35 KT 40 MPH
12H 16/1200Z 31.2N 76.7W 35 KT 40 MPH
24H 17/0000Z 31.0N 76.5W 30 KT 35 MPH
36H 17/1200Z 31.5N 76.5W 30 KT 35 MPH
48H 18/0000Z 31.5N 76.5W 30 KT 35 MPH
72H 19/0000Z 31.5N 76.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
96H 20/0000Z 32.5N 75.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 21/0000Z...DISSIPATED

$$
Forecaster Avila

NNNN

[northjaxpro]

Julia's tail end moisture actually extends west-southwest toward just south of Gainesville, FL.this hour. Yes, the exposed swirl is drifting south-southwest currently.

I am hoping Julia fades away, but I am a bit uneasy. Although the environment right now is not conducive for development, Julia's center is still spinning about almost back to Jacksonville's latitude , which a few models have this doing by this weekend. I mean it is like Julia wants to comeback for another unwanted dance with us in NE FL.

Stranger things have occured, which we have already seen this season with the tropical season, including this system.

Until I see this system dissipate completely and the fact Julia is still spinning out there just to our east here, we have to monitor closely the next few days.

[LarryWx]

Yes, indeed, Jax. I'd certainly keep monitoring if I were you.

Per latest IR: the naked swirl is still impressive on IR. It appears to have switched direction to SE at least for now. I can't tell whether or not it is about to do a loop. It appears to my eyeballs to be all of the way down to near 31.2N and 76.9W.