ATL INVEST 91L: Discussion

[HURAKAN]

12/1145 UTC 23.1N 71.0W T1.0/1.0 91L -- Atlantic Ocean

[cycloneye]

12:00 UTC BEST TRACK:

AL, 91, 2008091212, , BEST, 0, 228N, 715W, 25, 1013, DB,

[AdamFirst]

If this ends up developing, wouldn't they end up using Josephine again?

[gatorcane]

ABNT20 KNHC 121205
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT FRI SEP 12 2008

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON LARGE
HURRICANE IKE...LOCATED ABOUT 230 MILES SOUTHEAST OF GALVESTON
TEXAS.

AN AREA OF DISTURBED WEATHER...INCLUDING SOME OF THE REMNANTS OF
TROPICAL STORM JOSEPHINE...IS LOCATED ABOUT 200 MILES NORTHEAST OF
THE SOUTHEASTERN BAHAMAS. SOME SLOW DEVELOPMENT IS POSSIBLE OVER
THE NEXT COUPLE OF DAYS AS IT MOVES SLOWLY WEST-NORTHWESTWARD.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER ROBERTS/AVILA

well the wording has changed slightly more in favor of development. The previous couple of TWO's indicated "development IF ANY"...

the models that develop this wait for about 48-72 hours until it is over the Bahamas....then drive it WNW to NW into the SE Coast of Florida (or just along the East coast of Florida) but nothing strong at the moment.

[AJC3]

If this ends up developing, wouldn't they end up using Josephine again?

A couple days ago, my answer to this question was that IMHO they would b/c in my mind there was clear continuity between Josephine and this area of disturbed weather. Now I don't think they would anymore because it has gotten itself tangled up with a second area of disturbed weather that was out ahead of it. I think that's why this was designated a separate invest number 91L on NRL, and even the verbiage in the last few TWO's (i.e. "AN AREA OF DISTURBED WEATHER, INCLUDING THE PARTIAL REMNANTS OF JOSEPHINE") makes it clear to me that a new number/name would be used if it developed into something.

That having been said, I don't think it will develop. Aside from the NAM which (isn't really a global model, and) has a horrible bias toward TC-genesis, I haven't seen any global model really do very much with 91L (granted I haven't looked at the *cough* *gasp* ...CMC). Additionally, there's an UL trough immediately to it's west and a more well-defined ULL to it's NW that is dropping south. I think the convective flareups you're seeing with 91L are baroclinically enhanced (i.e. jet forced ascent) - meaning the shear that the trough to the west is imparting on 91L is divergent.

Something to watch...as it could enhance rain chances here in the FL east coast several days down the road should some of the vort energy hold together and actually get this far west.

[Sanibel]

Very weak center. Won't develop until Ike departs Gulf.

[jlauderdal]

If this ends up developing, wouldn't they end up using Josephine again?

A couple days ago, my answer to this question was that IMHO they would b/c in my mind there was clear continuity between Josephine and this area of disturbed weather. Now I don't think they would anymore because it has gotten itself tangled up with a second area of disturbed weather that was out ahead of it. I think that's why this was designated a separate invest number 91L on NRL, and even the verbiage in the last few TWO's (i.e. "AN AREA OF DISTURBED WEATHER, INCLUDING THE PARTIAL REMNANTS OF JOSEPHINE") makes it clear to me that a new number/name would be used if it developed into something.

That having been said, I don't think it will develop. Aside from the NAM which (isn't really a global model, and) has a horrible bias toward TC-genesis, I haven't seen any global model really do very much with 91L (granted I haven't looked at the *cough* *gasp* ...CMC). Additionally, there's an UL trough immediately to it's west and a more well-defined ULL to it's NW that is dropping south. I think the convective flareups you're seeing with 91L are baroclinically enhanced (i.e. jet forced ascent) - meaning the shear that the trough to the west is imparting on 91L is divergent.

Something to watch...as it could enhance rain chances here in the FL east coast several days down the road should some of the vort energy hold together and actually get this far west.

Boo Hoo

[fci]

If this ends up developing, wouldn't they end up using Josephine again?

A couple days ago, my answer to this question was that IMHO they would b/c in my mind there was clear continuity between Josephine and this area of disturbed weather. Now I don't think they would anymore because it has gotten itself tangled up with a second area of disturbed weather that was out ahead of it. I think that's why this was designated a separate invest number 91L on NRL, and even the verbiage in the last few TWO's (i.e. "AN AREA OF DISTURBED WEATHER, INCLUDING THE PARTIAL REMNANTS OF JOSEPHINE") makes it clear to me that a new number/name would be used if it developed into something.

That having been said, I don't think it will develop. Aside from the NAM which (isn't really a global model, and) has a horrible bias toward TC-genesis, I haven't seen any global model really do very much with 91L (granted I haven't looked at the *cough* *gasp* ...CMC). Additionally, there's an UL trough immediately to it's west and a more well-defined ULL to it's NW that is dropping south. I think the convective flareups you're seeing with 91L are baroclinically enhanced (i.e. jet forced ascent) - meaning the shear that the trough to the west is imparting on 91L is divergent.

Something to watch...as it could enhance rain chances here in the FL east coast several days down the road should some of the vort energy hold together and actually get this far west.

Thanks Tony for adding sensibility to this discussion.
Those who are getting hot and bothered, make sure you read

NEWS FLASH: Not every Invest is a threat to South Florida.

[dixiebreeze]

Looks like 91L is getting her groove on:

http://www.ssd.noaa.gov/goes/flt/t1/rb-l.jpg

[Weatherfreak000]

I am indeed still weary on development with this but becoming a little bit more intrigued...

24 hours of sustained convection and I think I can jump on the bandwagon. Overall, I think this has an alright shot to become Kyle.

[HURAKAN]

815
ABNT20 KNHC 121726
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT FRI SEP 12 2008

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON HURRICANE
IKE...LOCATED OVER THE NORTHWESTERN GULF OF MEXICO.

AN AREA OF DISTURBED WEATHER...INCLUDING SOME OF THE REMNANTS OF
TROPICAL STORM JOSEPHINE...IS LOCATED A COUPLE HUNDRED MILES
NORTHEAST OF THE SOUTHEASTERN BAHAMAS. SOME SLOW DEVELOPMENT OF
THIS SYSTEM IS POSSIBLE OVER THE NEXT COUPLE OF DAYS AS IT MOVES
SLOWLY WEST-NORTHWESTWARD.

SHOWERS AND THUNDERSTORMS HAVE INCREASED THIS AFTERNOON IN
ASSOCIATION WITH A TROPICAL WAVE LOCATED ABOUT 1400 MILES EAST OF
THE WINDWARD ISLANDS. DEVELOPMENT...IF ANY...OF THIS SYSTEM IS
EXPECTED TO BE SLOW TO OCCUR AS IT MOVES NORTHWESTWARD AT ABOUT
15 MPH.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER ROBERTS/BROWN

[RL3AO]

I. ATLANTIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. OUTLOOK FOR SUCCEEDING DAY: POSSIBLE LOW LEVEL
INVEST NEAR 25.0N 77.5W AT 14/1800Z WITH FOLLOW ON
6-HRLY FIXES BEGINNING AT 15/0600Z IF SYSTEM DEVELOPS

[gatorcane]

well it appears NHC has gained some interest in this area....

convection has been gradually on the increase here also.....

[jlauderdal]

we need to get ajc3 on board with this system, he had a good call on hanna surviving when it looked like it could collapse at any minute.

[cycloneye]

I think its time to bring a new family here apart from what jlauderdal posted back in the thread.

[AJC3]

we need to get ajc3 on board with this system, he had a good call on hanna surviving when it looked like it could collapse at any minute.

LOL...thx, however like I said earlier, I just don't like the look of the upper air pattern near this system with an upper trough to it's west providing quite a bit of upper tropospheric shear over and around the wave axis, and another upper low to the NW dropping southward.

http://www.ssd.noaa.gov/goes/east/nwatl/loop-wv.html

I'll take a better look at it, and some of the high res model data when I get into work (3 PM) to see if upper conditions look like they might improve. But for now, count me as still saying 'nyet' as far as development into a TC is concerned.

[jlauderdal]

I think its time to bring a new family here apart from what jlauderdal posted back in the thread.

these bears look more interested than this mornings polar bears

[HURAKAN]

This image is better to describe 91L. Just waiting for better conditions to develop but it's not in a hurry!!!

[jlauderdal]

we need to get ajc3 on board with this system, he had a good call on hanna surviving when it looked like it could collapse at any minute.

LOL...thx, however like I said earlier, I just don't like the look of the upper air pattern near this system with an upper trough to it's west providing quite a bit of upper tropospheric shear over and around the wave axis, and another upper low to the NW dropping southward.

http://www.ssd.noaa.gov/goes/east/nwatl/loop-wv.html

I'll take a better look at it, and some of the high res model data when I get into work (3 PM) to see if upper conditions look like they might improve. But for now, count me as still saying 'nyet' as far as development into a TC is concerned.

no peeking at what is going on around hou/galveston while on duty, the weather around east central florida looks really active later today which should keep everyone real busy

[AJC3]

no peeking at what is going on around hou/galveston while on duty, the weather around east central florida looks really active later today which should keep everyone real busy

Actually, from the looks of things, this evening's probably gonna be pretty tame. The AM crew's HWO/G-HWO mentioned only isolated lightning strikes over the interior in a deep onshore flow regime, and typically storms aren't all that intense and tend to pile up toward the west coast during deep easterlies.

http://www.srh.noaa.gov/mlb/ghwo/ghwomain.shtml
http://radar.weather.gov/radar.php?rid= ... 11&loop=no