ATL: ARTHUR - Post-Tropical - Discussion

['CaneFreak]

Yeah but it is already heading in the direction of the lower shear and the developing anticyclone. In fact, the current CIMSS analysis shows a well defined 700-850 mb vorticity lobe just north of the 30 N parallel off of the SC coast almost right underneath the developing anticyclone. Once it consolidates into one cohesive vortex (getting rid of the multiple swirls), it will be off to the races. Shear shouldn't be a problem. 55-60 knots from the EC is respectable in my opinion.

Please read what I post before commenting. I explained that SHIPS is an average. Furthermore, systems from a nontropical origin do form in higher shear enviroinments. If shear was only 10 KT, you wouldn't have the convection that far south of the center

As I said, shear is quite light to the SW. If this moves like the EC indicates, this will blow up. However, it has YET to encounter these conditions

[TropicalAnalystwx13]

The development of spiral banding in the northern semicircle indicates that 91L is becoming better organized, and also indicates that the shearing it underwent earlier has subsided as the anticyclone takes hold.

[hurricanefloyd5]

Is td #1 forming?

[hurricanes1234]

Note: If you're looking for live satellite coverage of this, go to the NRL Tropical Cyclones page. The SSD floaters have been down since 17:15 today.

[Alyono]

the convection is still very displaced from the center. It is not yet in the low shear area

['CaneFreak]

No. But it is moving into a more favorable environment. That's the takeaway msg this evening. Got it?

Is td #1 forming?

[Frank2]

The NHC web site seems to be having a problem at present (last satellite photo on their site is from 1715Z) - here's a link to the CIMSS site for current images of my non-system : )

http://tropic.ssec.wisc.edu/#

[SFLcane]

Impressive banding taking shape..i'd put the odds at 80-90% of TD minmal TS before heading out to sea. Heavy rains for FL.

[cycloneye]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT SAT JUN 28 2014

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

A broad area of low pressure located about 150 miles southeast
of the coast of South Carolina continues to produce disorganized
showers and thunderstorms. Environmental conditions are expected
to remain conducive for gradual development of this system while
it drifts southward offshore of Georgia and northeastern Florida
during the next few days. An Air Force Reserve Hurricane Hunter
aircraft is scheduled to investigate this system Sunday afternoon,
if necessary.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 5 days...high...60 percent.

$$
Forecaster Brennan

[Alyono]

while the chances of development appear too low, there was not a reason to increase the odds since 18Z. Not much change in organization and most models actually trended weaker (aside from EC)

[NDG]

while the chances of development appear too low, there was not a reason to increase the odds since 18Z. Not much change in organization and most models actually trended weaker (aside from EC)

The GFS has never done much with 91L, so which other models have trended weaker?

[SeGaBob]

Noaa's floaters appear to be working again... it's off of the 17:15Z frame anyway.

[Dean4Storms]

Impressive banding taking shape..i'd put the odds at 80-90% of TD minmal TS before heading out to sea. Heavy rains for FL.

I don't see heavy rains from Florida with this, they are on the drier side!

[SeGaBob]

We had a shower come through that NWS called the extreme NW part of 91L.

It dropped around 3/4 of rain in 20 minutes and now the sun has just come back out.

Edit: I saw a rainbow after the sun came back out.

[northjaxpro]

Beginning to see a blow-up of convection up near where I believe is the broad center about 100 miles east of Charleston, SC. 91L still has a broad circulation, but gradually it is slowly organizing. I think we may see a TD by the time Recon gets in there tomorrow afternoon.

[OuterBanker]

That six plus hour jump is very deceiving. Wait till the loops are clean again to get an accurate picture.

[hurricanes1234]

91L INVEST 140628 1800 32.1N 78.2W ATL 20 1017

Pressure is very high and strangely, it has increased a little since the last Best Track. Maybe if this forms we could see a >1010 mbar tropical cyclone?

[northjaxpro]

That six plus hour jump is very deceiving. Wait till the loops are clean again to get an accurate picture.

I was not aware of the jump in the loop. Thanks for letting me be aware of it. I am just checking in this evening

[TropicalAnalystwx13]

91L INVEST 140628 1800 32.1N 78.2W ATL 20 1017

Pressure is very high and strangely, it has increased a little since the last Best Track. Maybe if this forms we could see a >1010 mbar tropical cyclone?

Yeah, region-wide pressures are high. That's not necessarily a deterrent to development. The ECMWF shows this deepening into the low 990s.

[SeGaBob]

That six plus hour jump is very deceiving. Wait till the loops are clean again to get an accurate picture.

Now the loop looks clean again.