ATL: BERTHA - Post-Tropical - Discussion

[Hammy]

Given the winds and proximity to land, will they pull the trigger if it can manage to get convectively to a point similar to last night?

[TheAustinMan]

What's the longest a system has been consistently Code Red in the TWOs? 93L has been red in the 48 hour period since Tuesday, 2am, all except for being Orange last night at 8pm before going Red again at 2am today.

There was an Invest 93L in the open Atlantic back in early August 2010 that tracked from Cape Verde up into the open Atlantic and remained pegged at Code Red for 4 days (96 hours) straight and flipped between 60% and 70% probability before quickly petering out. This year's rendition of 93L probably won't beat that streak.
---------------------
As for the 93L approaching the Leeward Islands, convection seems to be popping up intermittently about but not over the center, and as for now the circulation center itself seems to be just a swirl of low clouds. Given the lack of convection over areas where recon documented TS-force winds, as others have stated this is probably winds associated with the burst of dry air combined a bit with the vorticity associated with 93L. Some new small convection is firing east of the center - we'll see how long that holds.

[NDG]

Perhaps it wouldn't hurt to have special flight missions in the MDR for the remainder of the hurricane season sampling the atmosphere to keep hurricane models from over developing tropical waves that way the NHC will have a better idea of what percentage to give for development. IMO.

I don't think its a data problem. Models are clearly showing how dry it is.

They are doing so now because 93L is closer to the islands but it was only 3 days ago that hurricane models were showing it becoming a hurricane in the middle of the Atlantic where there is lacking data to input into the models.

[StarmanHDB]

Not to give anyone a headache (well, a bigger one), but convection is popping again, on the right side of the LLC. It was around this time last night that convection started refiring, and held into the night.

Say what you will, but 93L is certainly a stubborn little burper!

[Sanibel]

Goes to show that cyclones do not live by spin alone.

[cycloneye]

Up to 80%.

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT THU JUL 31 2014

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

An Air Force Reserve reconnaissance aircraft this afternoon and
evening investigated the well-defined low pressure system located
about 350 miles east-southeast of Barbados, and found surface winds
of 40 to 45 mph across the northern and eastern portions of the
circulation. Showers and thunderstorms have increased east of the
center during the past couple of hours, and if this development
trend continues a tropical storm could form later tonight or early
Friday. Regardless of development, gale-force winds are likely to
spread across portions of the central Lesser Antilles beginning by
midday Friday. Interests in these areas should continue to monitor
the progress of this disturbance as it moves west-northwestward near
20 mph, since watches or warnings could be required for some of
these islands later tonight or Friday.
* Formation chance through 48 hours...high...80 percent.
* Formation chance through 5 days...high...80 percent.

$$
Forecaster Stewart

[Alyono]

the forecaster on duty tonight seems ready to upgrade...

[floridasun78]

Up to 80%.

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT THU JUL 31 2014

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

An Air Force Reserve reconnaissance aircraft this afternoon and
evening investigated the well-defined low pressure system located
about 350 miles east-southeast of Barbados, and found surface winds
of 40 to 45 mph across the northern and eastern portions of the
circulation. Showers and thunderstorms have increased east of the
center during the past couple of hours, and if this development
trend continues a tropical storm could form later tonight or early
Friday. Regardless of development, gale-force winds are likely to
spread across portions of the central Lesser Antilles beginning by
midday Friday. Interests in these areas should continue to monitor
the progress of this disturbance as it moves west-northwestward near
20 mph, since watches or warnings could be required for some of
these islands later tonight or Friday.
* Formation chance through 48 hours...high...80 percent.
* Formation chance through 5 days...high...80 percent.

$$
Forecaster Stewart

nhc not gaving up on 93l

[floridasun78]

http://www.nhc.noaa.gov/archive/xgtwo/g ... &fdays=5it up 80%

[Frank2]

True and it now appears to be moving WNW - right toward some pretty strong shear. Interestingly, as dry as the Caribbean has been here in South Florida we've had about 50 inches of rain in my local area since the start of the year (my roof is leaking)...

[floridasun78]

True and it now appears to be moving WNW - right toward some pretty strong shear. Interestingly, as dry as the Caribbean has been here in South Florida we've had about 50 inches of rain in my local area since the start of the year (my roof is leaking)...

put nhc dont think you way their want up 80%

[MGC]

I think this evening convective resurgance will push 93L over the top provided the convection continues to rebuild as we have observed the past several hours. I think it would be prudent to issue some kind of warning for the islands. I conjecture that 93L will get upgraded some time by morning......MGC

The above is the opinion of MGC and not an official forecast.

[tolakram]

IR Loop: http://wwwghcc.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20HURRICANE&lat=12&lon=-44&info=ir&zoom=2&width=1000&height=800&type=Animation&quality=95&palette=ir1.pal&numframes=5

Color: http://wwwghcc.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20HURRICANE&lat=12&lon=-44&info=ir&zoom=2&width=1000&height=800&type=Animation&quality=95&palette=ir2.pal&numframes=5

[cycloneye]

00z Best Track is with 40kts.

AL, 93, 2014080100, , BEST, 0, 120N, 547W, 40, 1008, LO

[Nimbus]

If the low level center stays naked more than a few hours the pressure gradient starts to diminish.
Obviously according to the NHC that isn't happening yet and with a track through the islands nobody is letting their guard down. Barbados will probably be on the weak side of the circulation but what about the other islands? Will there be enough shear and dry air to keep it from becoming a dangerous storm?

[Hammy]

While I still have very strong doubts that this will be upgraded given that it looked much better yesterday evening and wasn't, I will point out that if you watch the high clouds near the islands, they appear to be slowing down and moving more northward rather than eastward recently.

[cycloneye]

A reminder that we will have to wait until 10:30 PM thru 11 PM EDT to know if it was upgraded or not as the new policy is to not make public renumbers hours prior to advisory time.

[jaxfladude]

I hope this system(or any for that matter) does NOT have a surprise which noone wants...
Not a forecast! I am just being aware of past systems that pulled a nasty surprise ...

========
Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[northjaxpro]

NHC is waiting to see if the new convection just to the east of the LLC will sustain the next few hours. If the convection can hold up or even build slightly, they will probably upgrade late tonight. We will see.

[Frank2]

The S2K map no longer shows 93L - perhaps that's tomorrow's news today : )