ATL: HERMINE - Post-Tropical - Discussion

[tolakram]

live visible

http://weather.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20HURRICANE&lat=16&lon=-50&info=vis&zoom=1&width=1024&height=768&type=Animation&quality=92&palette=ir1.pal&numframes=5&mapcolor=gray&map=none

[GeneratorPower]

Nice convection this morning... Maybe NHC raises short term development percentages at 8??

I think they will, and same for 5 days. This system has a nice circulation that maintained itself when there was no convection. 99L might even be classified before reaching the islands

For 99L to impact Florida with significant winds, it's going to have to reach TD or TS status before the southeastern Bahamas. If it waits to get a good foundation until the central Bahamas it will not have time before it hits land.

[OuterBanker]

I think that the answer will be this.
Weaker and later development will mean the gulf scenario.
Earlier development and a stronger storm in the Bahamas will mean a southeast coast or out to sea.
Worse case will be a stall off the southeast coast in all that bathwater.

Jmho.

[Alyono]

I think that the answer will be this.
Weaker and later development will mean the gulf scenario.
Earlier development and a stronger storm in the Bahamas will mean a southeast coast or out to sea.
Worse case will be a stall off the southeast coast in all that bathwater.

Jmho.

Maybe not

Stronger may mean Gulf. Depends upon how deep the ridge is

[srainhoutx]

Maybe not

Stronger may mean Gulf. Depends upon how deep the ridge is

I tend to agree. The ECMWF and GFS Ensembles remain in fairly good agreement that the SE Ridge will be well established later this week throughout the weekend into early next week.

[LarryWx]

Note that 99L is getting more convection at around 50W (due to higher SST's?), which is where those runs of the GFS/GEFS of a couple of days ago that had it developing by the Lesser Antilles first had it start to develop. Of course, we know they now wait til near the Bahamas for development.

[Weatherboy1]

Nice convection this morning... Maybe NHC raises short term development percentages at 8??

I think they will, and same for 5 days. This system has a nice circulation that maintained itself when there was no convection. 99L might even be classified before reaching the islands

For 99L to impact Florida with significant winds, it's going to have to reach TD or TS status before the southeastern Bahamas. If it waits to get a good foundation until the central Bahamas it will not have time before it hits land.

I don't know. Some of the models seem to suggest 99 will have time to linger in the Bahamas - over some of the warmest water in the entire Atlantic basin. Upper-level winds are a key factor in terms of potential strength, too. But a system approaching from the SE, slowing and strengthening, then getting turned to the W/WNW and hitting the FL east coast is a potentially worrisome scenario. We haven't really seen anything like that here since Frances and Jeanne in 2004. Still plenty of time to watch, though, and see what unfolds in the modelling.

[Weatherboy1]

Note that 99L is getting more convection at around 50W (due to higher SST's?), which is where those runs of the GFS/GEFS of a couple of days ago that had it developing by the Lesser Antilles first had it start to develop. Of course, we know they now wait til near the Bahamas for development.

This is definitely a noteworthy development. We've gone from a "naked swirl" to a system that is firing off rather significant convection - though it still lacks organization. Plus, that convection has persisted for many, many hours, also something we haven't seen up until this point. Hmmm.

[Emmett_Brown]

Note that 99L is getting more convection at around 50W (due to higher SST's?), which is where those runs of the GFS/GEFS of a couple of days ago that had it developing by the Lesser Antilles first had it start to develop. Of course, we know they now wait til near the Bahamas for development.

This is definitely a noteworthy development. We've gone from a "naked swirl" to a system that is firing off rather significant convection - though it still lacks organization. Plus, that convection has persisted for many, many hours, also something we haven't seen up until this point. Hmmm.

Yep, starting to look like a more classic area of disturbed weather now. And, it is a couple of days away from the islands, so still some time to develop, assuming it doesn't go poof today.

[LarryWx]

Note that 99L is getting more convection at around 50W (due to higher SST's?), which is where those runs of the GFS/GEFS of a couple of days ago that had it developing by the Lesser Antilles first had it start to develop. Of course, we know they now wait til near the Bahamas for development.

This is definitely a noteworthy development. We've gone from a "naked swirl" to a system that is firing off rather significant convection - though it still lacks organization. Plus, that convection has persisted for many, many hours, also something we haven't seen up until this point. Hmmm.

This was what the 6Z GEFS was showing three days ago: Note that it has actually made it to 50W about a day earlier than projected (Mon vs Tue). I wonder if the faster speed than then progged is why they no longer develop it between 50W and the Lesser Antilles:

"Looking at the 20 6Z GEFS members, virtually all of them wait til about Tuesday, when it is near 50W, to develop at all. Subsequently, nearly all 20 of them develop between 50W and the Lesser Antilles Tue-Wed."

[Hurricaneman]

Honestly this is the best this has looked since around 35W and seems to be following the development pattern that the GFS had about 3 to 4 days ago

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[wxman57]

I think it's behaving just as had been forecast. Never expected it to develop any convection until it got closer to the eastern Caribbean. The NHC shouldn't have begun doubting development yesterday because it lacked convection. Take a look at the MIMIC-TPW loop (as I've said). Quite a lot of moisture & energy, and quite a circulation. It could potentially be a Gulf threat, but I'm thinking it has a better chance of tracking into the Bahamas then turning north.

[cycloneye]

The squadron will be very active starting on Tuesday afternoon.Plane departs at 9 AM EDT.

Code: Select all

WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1015 AM EDT MON 22 AUGUST 2016
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
         VALID 23/1100Z TO 24/1100Z AUGUST 2016
         TCPOD NUMBER.....16-088

I.  ATLANTIC REQUIREMENTS
    1. SUSPECT AREA (NEAR LESSER ANTILLES)
       FLIGHT ONE - TEAL 70           FLIGHT TWO - TEAL 71
       A. 23/1500Z                    A. 23/2330Z,24/0530Z
       B. AFXXX 01EEA INVEST          B. AFXXX 0208A CYCLONE
       C. 23/1300Z                    C. 23/2200Z
       D. 16.0N 56.5W                 D. 16.5N 59.0W
       E. 23/1445Z TO 23/1800Z        E. 23/2300Z TO 24/0530Z
       F. SFC TO 10,000 FT            F. SFC TO 10,000 FT

       FLIGHT THREE - TEAL 72
       A. 24/1130Z,1730Z
       B. AFXXX 0308A CYCLONE
       C. 24/1030Z
       D. 17.5N 62.0W
       E. 24/1100Z TO 24/1730Z
       F. SFC TO 10,000 FT

    2. SUCCEEDING DAY OUTLOOK: CONTINUE 6-HRLY FIXES IF SYSTEM
       DEVELOPS AND IS A THREAT.

[Frank2]

This is a good view of now sheared Fiona and the boundary that might be causing the 99L flare:

http://www.goes.noaa.gov/HURRLOOPS/huirloop.html

[Bocadude85]

I think it's behaving just as had been forecast. Never expected it to develop any convection until it got closer to the eastern Caribbean. The NHC shouldn't have begun doubting development yesterday because it lacked convection. Take a look at the MIMIC-TPW loop (as I've said). Quite a lot of moisture & energy, and quite a circulation. It could potentially be a Gulf threat, but I'm thinking it has a better chance of tracking into the Bahamas then turning north.

Any thoughts on a potential Florida/SE Coast threat or are you thinking out to sea after the Bahamas?

[SueOrleans]

It could potentially be a Gulf threat, but I'm thinking it has a better chance of tracking into the Bahamas then turning north.

I always appreciate your measured approach.

Hopefully it stays out of the Gulf, or at least away from Louisiana. I don't think anybody here wants to see rain again for a while.

[chaser1]

I think it's behaving just as had been forecast. Never expected it to develop any convection until it got closer to the eastern Caribbean. The NHC shouldn't have begun doubting development yesterday because it lacked convection. Take a look at the MIMIC-TPW loop (as I've said). Quite a lot of moisture & energy, and quite a circulation. It could potentially be a Gulf threat, but I'm thinking it has a better chance of tracking into the Bahamas then turning north.

Any thoughts on a potential Florida/SE Coast threat or are you thinking out to sea after the Bahamas?

my thought: West Palm Beach to Vero (977mb)

[Weatherboy1]

Last couple of frames on the visible satellite appear (to me anyway) to be showing some consolidation of a potential center of circulation around 16.5/50.5. Will be interesting to see if that persists ... and whether or not I'm just seeing things after watching too many loops

[Frank2]

This is a good map graphic - hopefully the series of fronts will leave enough of a trough to force it northward...

http://www.nws.noaa.gov/outlook_tab.php

[Weatherboy1]

I think it's behaving just as had been forecast. Never expected it to develop any convection until it got closer to the eastern Caribbean. The NHC shouldn't have begun doubting development yesterday because it lacked convection. Take a look at the MIMIC-TPW loop (as I've said). Quite a lot of moisture & energy, and quite a circulation. It could potentially be a Gulf threat, but I'm thinking it has a better chance of tracking into the Bahamas then turning north.

Any thoughts on a potential Florida/SE Coast threat or are you thinking out to sea after the Bahamas?

my thought: West Palm Beach to Vero (977mb)

Some kind of hybrid of the tracks for Erin (1995)/Frances (2004)/Jeanne (2004) is definitely a possibility. But we are still talking about several days out, so the "windshield wiper" model pattern needs to resolve before getting too definitive, in my opinion.