ATL: BONNIE - Post-Tropical - Discussion

[wxman57]

The LLC is still west of the convection this evening (SW shear). I think it'll become TD Two tomorrow afternoon and TS Bonnie on Saturday. I'm thinking 50kt TS making landfall near Charleston, SC Sunday afternoon then slowing down and tracking NNE-NE along the coast or just inland for 48-72hrs, slowly weakening as it does so. May finally eject NE and offshore for good Wednesday afternoon as it merges with a frontal boundary. Lots of nasty weather for coastal areas of the Carolinas this holiday weekend. Probably won't become a hurricane, but I wouldn't rule that out 100%. Water temps are still a bit cool near the coast.

[tolakram]

live IR

http://weather.msfc.nasa.gov/cgi-bin/ge ... olor=black

[WilmingtonSandbar]

Had a boat captain that was bringing a boat from Palm Beach Florida to Maryland tell me in Southport NC tonight that he was tracking SSTs in the gulf stream at a steady 81 degrees from Florida to Southport.

[TheStormExpert]

The key to determining 91L's peak intensity will be how much time it spends over the narrow tongue of the Gulf Stream.

[Hammy]

I'm thinking this isn't upgraded until Saturday at the earliest--ASCAT seems less organized than yesterday's pass and indicates it may not even be closed at the moment.

[TheStormExpert]

0z Euro comes in much weaker.

The 0z HWRF has now just a weak TS into SC.

[NDG]

I'm thinking this isn't upgraded until Saturday at the earliest--ASCAT seems less organized than yesterday's pass and indicates it may not even be closed at the moment.

The last time ASCAT was able to catch its circulation before Thursday night's it was Wednesday night and it only caught its eastern side of the circulation, so not a good comparison to the latest one.
This looks like the typical weak system at this point when is moving along westward with the lower flow, there are a few weak west winds found by ASCAT so it is a closed circulation, but a bit elongated still.

[NDG]

I did not see anybody post the reports from the buoy when 91L's COC passed just to the south of it, I would say 40-50 miles south of it with a wind gust of 42 mph.

http://www.ndbc.noaa.gov/station_page.php?station=41047

05 26 11:40 pm E 21.4 29.1 - -29.91
05 26 11:30 pm ENE 21.4 29.1 - 29.91
05 26 11:20 pm ENE 25.3 31.1 - 29.91
05 26 11:10 pm ENE 27.2 33.0 - 29.91
05 26 11:00 pm ENE 27.2 33.0 - 29.91
05 26 9:50 pm ENE 27.2 36.9

[stormwise]

Sheared but when recon goes in i think this will be named.

[drezee]

I did not see anybody post the reports from the buoy when 91L's COC passed just to the south of it, I would say 40-50 miles south of it with a wind gust of 42 mph.

http://www.ndbc.noaa.gov/station_page.php?station=41047

05 26 11:40 pm E 21.4 29.1 - -29.91
05 26 11:30 pm ENE 21.4 29.1 - 29.91
05 26 11:20 pm ENE 25.3 31.1 - 29.91
05 26 11:10 pm ENE 27.2 33.0 - 29.91
05 26 11:00 pm ENE 27.2 33.0 - 29.91
05 26 9:50 pm ENE 27.2 36.9

Also, 36 mph sustained 1-min wind

[TheStormExpert]

Sheared but when recon goes in i think this will be named.

Recon could always be canceled if it doesn't organize further.

We'll know more in the next Special TWO.

[Nimbus]

Looks like it just drifted west overnight.
Should pass 73W near 28N.
Highest winds are not near the center so the pressure gradient may be shallow, but its clearly a TD.

[cycloneye]

Recon is going at 11 AM EDT.

90%-90%

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT FRI MAY 27 2016

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

Shower activity associated with the low pressure area located
between Bermuda and the Bahamas continues to show signs of
organization, and the circulation of the low has become a little
better defined overnight. Environmental conditions are generally
conducive for a tropical or subtropical cyclone to form later today
or Saturday while this system moves west-northwestward to
northwestward toward the southeastern United States coast. All
interests along the southeast coast from Georgia through North
Carolina should monitor the progress of this low. An Air Force
Reserve Hurricane Hunter aircraft is scheduled to investigate the
low this afternoon. The next Special Tropical Weather Outlook on
this disturbance will be issued by 3 PM EDT this afternoon. For
additional information on this system, see High Seas Forecasts
issued by the National Weather Service.
* Formation chance through 48 hours...high...90 percent
* Formation chance through 5 days...high...90 percent

&&
High Seas Forecasts issued by the National Weather Service can be
found under AWIPS Header NFDHSFAT1 and WMO Header FZNT01 KWBC.

$$
Forecaster Stewart

[tolakram]

live visible

http://weather.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20CONUS&lat=28&lon=-73&info=vis&zoom=1&width=1000&height=800&quality=90&type=Animation&palette=ir1.pal&numframes=8&mapcolor=black

[cycloneye]

12z Best Track:

AL, 91, 2016052712, , BEST, 0, 276N, 729W, 30, 1009, LO

Location: 27.6°N 72.9°W
Maximum Winds: 30 kt Gusts: N/A
Minimum Central Pressure: 1009 mb
Environmental Pressure: 1014 mb
Radius of Circulation: 110 NM
Radius of Maximum Wind: 50 NM

[AutoPenalti]

1st Naked swirl of the season(?)

[cycloneye]

@EricBlake12

Interesting in seeing recon this pm to see the SW side of #AL91- surface circulation not exactly classic on 1st vis

[CrazyC83]

It looks like the winds are stronger (35 or 40 kt) but it lost its circulation...

[Alyono]

looks to be a closed circulation

[tarheelprogrammer]

looks to be a closed circulation

I can see the circulation well on visible. It looks less organized than yesterday though but could be my untrained eyes telling me that. Not sure why NHC upped the percentages but they will surely be right. Just wondering what they see. I thought this storm was going to be more organized by now than it is.

Also, there is what appears to be a spin right on top of the Bahama islands. It is at 24N and 75W but I could be wrong.

Levin Cowan posted on twitter "Seeing big negatives now for development of 91L. Speed convergence forecast aloft on eastern flank of upper trough:"