ATL: TROPICAL DEPRESSION ALEX - DISCUSSION

[Chacor]

Recon cancelled for the second day in a row.

ABNT20 KNHC 241138
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT THU JUN 24 2010

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

A TROPICAL WAVE OVER THE WESTERN CARIBBEAN SEA CONTINUES TO
PRODUCE SHOWERS AND A FEW THUNDERSTORMS ACROSS PORTIONS OF
HISPANIOLA...JAMAICA...CUBA...THE CAYMAN ISLANDS...AND THE ADJACENT
WATERS OF THE NORTHERN CARIBBEAN SEA. THIS SYSTEM HAS CHANGED
LITTLE IN ORGANIZATION OVER THE PAST SEVERAL HOURS...WITH MOST OF
THE SHOWER AND THUNDERSTORM ACTIVITY OCCURRING TO THE EAST OF THE
WAVE AXIS...AND THE AIR FORCE RESERVE UNIT RECONNAISSANCE AIRCRAFT
MISSION TO INVESTIGATE THE AREA TODAY HAS BEEN CANCELED.
UPPER-LEVEL WINDS ARE EXPECTED TO BECOME MORE CONDUCIVE FOR
DEVELOPMENT OF THIS SYSTEM AS IT MOVES WESTWARD OR WEST-
NORTHWESTWARD AROUND 10 MPH OVER THE NEXT COUPLE OF DAYS. THERE IS
A MEDIUM CHANCE...40 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL
CYCLONE DURING THE NEXT 48 HOURS.

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

$$
FORECASTER PASCH/CANGIALOSI

[KWT]

On the plus side, the storms are now more concentrated...on the negative side, they are not living very long, nor are they really deep.

Yeah thats because upper divergence is really poor with the actual wave feature and indeed looks more like convergence thenb divergence, which at upper levels is never going to be condusive for sustained development of storms. Until this changes, I'd be surprised if anything developed, esp as the Yucatan isn't that far away...

[jlauderdal]

I see some cyclonic turning near 17N-76W this morning - probably at the mid-levels.

http://www.ssd.noaa.gov/goes/flt/t1/flash-rgb.html

nothing concentrated in that loop, no go today

[wxman57]

By the way, all the storms SE of Jamaica where the system appears to be consolidating is NOT the same wave that generated 93L. That wave has moved out west of 80W and another has come in from the east. We tracked both waves since Africa for the past 10 days. In fact, the models actually appeared to be developing this 2nd wave and not the one in front that was identified as 93L. Regardless, the place to watch is SE of Jamaica not west of 80W where the models were initialized.

[wx247]

Well the night came and went... while this system is in a much better place than it was 24 hours ago, it is still fighting to get going. I guess it is time for another wait and watch day. I think whoever said to quit watching and come back on Friday was very smart.

[KWT]

So what is going to happen wxman57, will they decide to keep it as invest 93L or actually make invest 94L if it looks like that area is developing.

It certainly makes sense that the models are developing that region though because the ECM doesn't landfall till 72hrs time.

[wxman57]

So what is going to happen wxman57, will they decide to keep it as invest 93L or actually make invest 94L if it looks like that area is developing.

It certainly makes sense that the models are developing that region though because the ECM doesn't landfall till 72hrs time.

I hope not. Just keeping the area 93L would be less confusing. Look for the models to be re-initialized farther east later today or tomorrow. I wouldn't pay too much attention to them now.

[HURAKAN]

Latest

[rockyman]

By the way, all the storms SE of Jamaica where the system appears to be consolidating is NOT the same wave that generated 93L. That wave has moved out west of 80W and another has come in from the east. We tracked both waves since Africa for the past 10 days. In fact, the models actually appeared to be developing this 2nd wave and not the one in front that was identified as 93L. Regardless, the place to watch is SE of Jamaica not west of 80W where the models were initialized.

Could this explain the "twin systems" that CMC keeps spinning up? Or, am I giving CMC too much credit?

[srainhoutx]

I suspect that 93L will remain the primary focus. This has been a broad area lower pressures from the beginning with several waves. Remember the multiple solutions we have seen from various guidance of several low pressure centers.

[KWT]

So what is going to happen wxman57, will they decide to keep it as invest 93L or actually make invest 94L if it looks like that area is developing.

It certainly makes sense that the models are developing that region though because the ECM doesn't landfall till 72hrs time.

I hope not. Just keeping the area 93L would be less confusing. Look for the models to be re-initialized farther east later today or tomorrow. I wouldn't pay too much attention to them now.

Yeah I think your right, certainly the area to the east does have better upper divergence, I also think a west track towards Yucatan and into S.Mexico would be favoured in that solution.

[rockyman]

SSD did a "partial relocation" during the night (from 79.5 to 77.8):

24/1145 UTC 16.2N 78.9W TOO WEAK 93L
24/0545 UTC 16.8N 77.8W TOO WEAK 93L
23/2345 UTC 17.0N 79.5W TOO WEAK 93L

[HouTXmetro]

Call me crazy but if Wxman is right I think we are witnessing the Fujiwara effect. I know there are not two clearly defined circulation but it appears 93L was trying to get going just SW of Jamaica last night and it's vortice/circulation has been moving SSW while the feature behind is rotating and interacting to it's NE. Is that a plausible explanation as to why 93L hasn't been able to get it's act together? the feature behind it has been steadily zapping it's energy.

[cwachal]

the Fujiwara affect is defined as 2 tropical systems rotating around each other but these are not tropical systems

[HouTXmetro]

the Fujiwara affect is defined as 2 tropical systems rotating around each other but these are not tropical systems

Aren't these two Tropical Waves with a sharp axis? I'm not a met and I'm not saying it's text book Fujiwara but maybe something of the sort.


en.wikipedia.org/wiki/Fujiwhara_effect
The Fujiwhara effect or Fujiwara interaction is a type of interaction between two nearby cyclonic vortices

[rockyman]

Call me crazy but if Wxman is right I think we are witnessing the Fujiwara effect. I know there are not two clearly defined circulation but it appears 93L was trying to get going just SW of Jamaica last night and it's vortice/circulation has been moving SSW while the feature behind is rotating and interacting to it's NE. Is that a plausible explanation as to why 93L hasn't been able to get it's act together? the feature behind it has been steadily zapping it's energy.

The steering currents could also explain the movement of these systems:

[KWT]

Is that a plausible explanation as to why 93L hasn't been able to get it's act together? the feature behind it has been steadily zapping it's energy.

Sort of, more like the first wave never had good enough conditions aloft with regards to creating instablity whilst the better region for that was further east, plus the shear looks just a little bit weaker on that side as well.

[cycloneye]

Another hurdle that may cause some problems for whatever this Caribbean Disturbance be down the road may be the outflow from Darby if it moves into the BOC.

[cycloneye]

12 UTC Best Track

AL, 93, 2010062412, , BEST, 0, 165N, 796W, 25, 1008,WV

[HURAKAN]

Getting tired of 93L. lol