ATL: KARL - Ex-Hurricane - Discussion

[KWT]

Probably have recon on Saturday I'd imagine for this system in the E.Caribbean as well, so the next round of recon fun is likely soon!

[bvigal]

[ConvergenceZone]

Even if this does hit Mexico, I think Northern Mexico is much more likely, based upon all of the current model data....

[Bailey1777]

if we get a spin up everything looks very conducive to me, wonder if we will gain some latitude in this area as ex gaston did when he came through.

[tailgater]

http://a.imageshack.us/img85/6053/atlsfc72latestbwsm3.gif

In no hurry to move, that could be horrible if conditions are favorable.

Luis, now it's right!

Steering is pretty weak, maybe a due west? Unless it develops early as the NAM is showing.

[ColinDelia]

This factor may be way SHIP goes bonkers on intensity.

Of the 81 knot increase forecast by SHIPS through 120 hours, there are 96 knots of positive factors and 15 knots of negative factors.

Of the positive factors:
44 knots comes from maximum potential intensity (actually the difference between current intensity and MPI)
20 knots comes from vertical shear direction
13 knots comes from typical intensity changes for this time of year
6 knots from Ocean Heat Content
5 knots from 200 mb divergence
8 knots from 4 additional factors less than 5 knots contribution each

There are 5 negative factors summing up to the 15 knots of negative contributions

[KWT]

Yeah I agree CZ, I wouldn't be all that shocked to see this end up close to where Alex did on its last landfall but its very early in the day for that sort of speculation to be fair!

[ConvergenceZone]

Yeah I agree CZ, I wouldn't be all that shocked to see this end up close to where Alex did on its last landfall but its very early in the day for that sort of speculation to be fair!

I agree, it's too early to speculate. For all we know, this could be caught up in a weakness that will push this right up into Texas, too early to say...This time of year, there is much more in the area of weakness than there is in July or August.

[KWT]

Tailgator, yeah the steering currents are really slack right now hence why this system is progged to only have very slow movement in the next 3-4 days before the upper ridge starts to strengthen and take it W/WNW at a quicker pace.

[USTropics]

This has Jeff Master's full attention:

A tropical disturbance (92L) has developed over the extreme southeastern Caribbean just north of the coast of South America, over the southernmost Lesser Antilles Islands. Surface observations indicate that pressures have been slowly falling at a number of stations, and satellite loops show a modest region of heavy thunderstorm activity is building. A strong flow of upper level easterly winds is creating a moderate 10 - 20 knots of wind shear, and the waters are plenty warm for development. Water vapor satellite loops show a large area of dry air lies over the northern Caribbean, but this dry air should not interfere with development over the next two days.

The disturbance is slowly drifting westward, but steering currents favor a more northwest motion Friday and Saturday. Lower shear lies over the Central Caribbean, away from the coast of South America, so any northward component of motion will allow for more significant development. There is drier air to the north, but 92L is steadily moistening the atmosphere in the Caribbean, so dry air may not be a problem for it. There is substantial model support for development. The disturbance is in a dangerous location for development, and gives me the greatest concern of any Atlantic disturbance so far this year. The models predict that by Saturday, 92L will bring heavy rains to Puerto Rico. These rains will then spread to the Dominican Republic on Sunday, and Haiti, Jamaica, and eastern Cuba on Monday. The longer range track of 92L is uncertain, and will strongly depend on where the storm drifts during the next two days. The ECMWF and GFS models predict a more southerly path through the Western Caribbean towards Belize and Mexico's Yucatan Peninsula, and the NOGAPS and Canadian models predict a more northerly path along the length of Cuba towards Florida. NHC is giving 92L a 40% chance of developing into a tropical depression by Saturday. Stay tuned.

[ColinDelia]

[ConvergenceZone]

Basically what Jeff Masters is saying is that this can go anywhere from Florida to Mexico.

[Bailey1777]

anybody with access have j.b.'s thoughts on this?

[cycloneye]

I haven't seen Dr Masters so concerned this season like what he is expressing today. I can imagine,that statement will open eyebrows for many.

[Riptide]

That is quite the outflow boundary on the latest visual. It really gives an illusion of some convective organization.

[bvigal]

A sobering post by Masters. If you held a gun to my head this very minute to decide, I'd go with the forecasters in PR, who doubted that NAM run this morning. They wrote no changes on the topic in their 10:10am update. It doesn't sound like "further north" necessarily means over PR. If they change their analysis in next update, it would increase my concern of system tracking over PR/VI.
"AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1019 AM AST THU SEP 9 2010
...
OF NOTE IS THEUNRELIABLE MODELS CANADIAN GLOBAL AND NAM INDICATE THIS SYSTEM ACTUALLY MOVING ACROSS PR ON SUN. GIVEN THAT THE H25 HIGH IS EXPECTED TO WEAKEN AND UPPER LVL TROUGH XPCD TO CONTINUE TO DIG SOUTH IS NOT OUT THE REALM OF POSSIBILITIES THAT THIS SYSTEM COULD END UP FURTHER NORTH THAT WHAT IS SUGGESTED BY THE GFS/ECMWF MODELS."

[JtSmarts]

anybody with access have j.b.'s thoughts on this?

This article from accuweather sums up his thoughts about the future of Igor and 92L

http://hurricane.accuweather.com/blogs/ ... ccuweather

[cycloneye]

Probably have recon on Saturday I'd imagine for this system in the E.Caribbean as well, so the next round of recon fun is likely soon!

You got it right. On Saturday afternoon will be the first mission. There will be one tommorow,but that one will fly very high in the Atmosphere.

WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1130 AM EDT THU 09 SEPTEMBER 2010
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 10/1100Z TO 11/1100Z SEPTEMBER 2010
TCPOD NUMBER.....10-101

I. ATLANTIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. SUCCEEDING DAY OUTLOOK: PSBL LOW LEVEL INVEST
NEAR 14.0N AND 64.0W FOR 11/1800Z.
3. REMARKS: THE NSF/NCAR G-V WILL FLY 2 A DAY RESEARCH MISSIONS
DEPARTING AT 10/0900Z AND 1700Z INTO THE SAME AREA.

[Typhoon_Willie]

Just was curious if there were any radars in the area and along the path of 92l.

[WeatherEmperor]

Does anybody think that the fact that it is still so close to land, may prohibit development in the short term?