Models Develop a Disturbance Near Florida (Is invest 90L)

[Ivanhater]

Again, Im hoping this thing is a phantom storm, I want nice hot sunny weather for the beach this memorial day weekend!

[RL3AO]

When will they start running the GFDL and HWRF -- two excellent models in my opinion?

Those models don't run until the NHC tags it as an invest.

[jinftl]

warmer than i would have thought to be honest...low to mid 80's go pretty far north....at least to the latitude of west-central peninsula....could any of the temps shown maintain a system that could develop....of course, this is not like looking at what happens to water temps, say, north of cape hatteras

well here is some sst measurements for the eastern Gulf
http://www.nodc.noaa.gov/dsdt/cwtg/egof_tmap.html

[Ed Mahmoud]

This plot of the depth of the 26ºC doesn't seem right to me.



Looks too deep, too early. But assuming it is valid:


Still would not support a storm very well over the Northeast GOMEX, although I suppose baroclinic enhancement could keep a gale center of semi-tropical nature going over water cooler than what is normally required.

[Aric Dunn]

I checked the SSTs in the GOM based on NOAA reports. Here is what they are:

Station 42039 - 79.5F (about 150 miles South of Pensacola)
Station 42012 - 81.5F (about 25 miles off of Mobile, Alabama)
Station 42004 - 81.7F (about 200 miles West of Naples, FL)

Generally, we are seeing 78F-81F in the GOM from north to south respectively. Are these August temperatures? No.

The minimum threshold for supporting tropical storms is 78F -- and with about 1+ week of late May sun until something even gets into the Northern GOM, I really do expect at least 1F-2F degree warming in about a week.

link:
http://www.ndbc.noaa.gov/

look...
the only applicable sst which is what i have talking about If the system were to DEVELOP in the NE gulf !! would be the station 42039.
but even in the SE GULF WE ARE GOING TO SEE STRONG WINDS BEFORE THE ACTUALLY POSSIBILITY OF A FULLY TROPICAL SYSTEM CAN DEVELOP> WITH THAT SAID THESE WINDS WILL BEGIN TO UP WELL AND MIX THE MUCH MUCH COOLER( very very shallow ssts) WATER FROM BELOW THUS MAKING IT EVEN HARDER TO GET A FULLY TROPICAL SYSTEM. not saying a sub-trop could not form i have talking about purely tropical.

[jinftl]

Water warm enough to maintain a weak, probably disorganized system is definitely not the same as water warm enough, and warm enough to some depth, to support rapid intensification. It's maintaining a system vs. enhance/support rapid development that may be the distinction that is key here.

And again, a system developing in 80-84 degree water and moving into an area 78-80 deg is different than a system that is trying to develop in 78 deg water. Would we see a textbook looking cyclone....doubtful, but a wet and messy and squally mess could do it's thing in water much cooler than that even.

[Aric Dunn]

This plot of the depth of the 26ºC doesn't seem right to me.



Looks too deep, too early. But assuming it is valid:


Still would not support a storm very well over the Northeast GOMEX, although I suppose baroclinic enhancement could keep a gale center of semi-tropical nature going over water cooler than what is normally required.

that area with much higher depth is the gulf loop.. its very typical and last all year ..

here is a older loop..but shows the Gulf loop nicely..
its kind of difficult to follow since the scale changes each frame but look at it long enough you figure it out
http://www.opc.ncep.noaa.gov/Loops/SST_ ... _Day.shtml

[Ivanhater]

Navy further west and south

[cycloneye]

12z NOGAPS west and more south



http://moe.met.fsu.edu/cgi-bin/ngptc2.c ... =Animation

[Ed Mahmoud]

I find today's HPC model discussion somewhat uninformative, probably because they aren't at all sure what might happen.

SOUTHEAST US/FL/GULF OF MEXICO...
THERE IS GOOD AGREEMENT A BROAD AREA OF LOW PRESSURE OVER THE
NORTHWEST CARIBBEAN DRIFTS NORTHWEST WITH TIME INTO THE GULF OF
MEXICO UNDER AN UPPER LOW OVER THE EASTERN GULF THAT CLOSES OFF BY
00Z WED 20 MAY AND MOVES SLOWLY WITH TIME. A LARGE SPRAWLING AREA
OF LOWER HEIGHTS/PRESSURES IS FCST BY ALL OF THE MODELS...WITH THE
00Z GFS SLIGHTLY DEEPER/FURTHER NORTH WITH ITS LOW CENTER THAN THE
ECMWF/UKMET/CANADIAN MODELS AND ECMWF/NCEP MEANS. THE 06Z GFS
TRENDED NORTH WITH THE CIRCULATION SFC AND ALOFT AND LOOKS TO BE
AN OUTLIER SOLUTION SO NO CHANGES WERE MADE FOLLOWING THE 06Z GFS.
A BLENDED SOLUTION WAS USED HERE DUE TO THE WIDE SPREAD OF WHERE
THE SFC CENTER (OR CENTERS) WILL BE LOCATED WITHIN THE LG AREA OF
LOW PRESSURE/HEIGHTS.

[jinftl]

When extra-tropical processes are involved in the development of a tropical or sub-tropical system, does the water temperatures necessarily have to be that warm?

[Ed Mahmoud]

Euro out on PSU e-Wall through 72 hours...

[NDG]

12z Euro definitely faster on cyclogenisis than previous runs, starts it closer to the FL straights than last night's runs.

[cycloneye]

12z ECMWF

[Ed Mahmoud]

When extra-tropical processes are involved in the development of a tropical or sub-tropical system, does the water temperatures necessarily have to be that warm?

In my unprofessional understanding, if the upper atmosphere is cooler than normal, such that cooler water produces a similar temperature gradient between the surface and upper atmosphere, than slightly sub-26º waters might still support a weak tropical system.

Of course, in a less than purely tropical system, jet stream interaction helping lift the air from the surface, and temperature/humidity gradient effects too, might help.



I direct your attention to purely non-tropical systems that seem to get enhanced by the warmer water of the Gulf Stream, like certain Northeast US winter Nor-Easters. Heat released by thunderstorms over the warmer water seem to add extra energy, and I have even noticed anticyclonic streaming of cirrus around these systems on satellite, as if they have acquired weakly warm core charecteristics aloft, even with fronts and snow at the surface.

Non-professional opinion.

[Tampa Bay Hurricane]

I certainly think there will be a strong low pressure area...
whether or not it is tropical...it will have a large area
of squalls that produce tropical storm force wind gusts...
especially with cold air aloft- stronger cells could easily
go severe...and severe storms can produce winds
in excess of 50 mph.

[Bailey1777]

Correct me if I'm wrong but until we have, if we do a low pinch off, every model run is going to be all over the place and the only certanty that we have is if forementioned low does pinch off it is going to be one of those long drawn out processes for it to become truly tropical if it ever does.

[NDG]

When extra-tropical processes are involved in the development of a tropical or sub-tropical system, does the water temperatures necessarily have to be that warm?

No, they do not have to be that warm, as low as the mid 70s a system can gain subtropical charecteristics.

[Ed Mahmoud]

Euro's strongest winds (see link above) somewhat removed from low center, suggesting, in its own little way, not a purely tropical system.

[Ivanhater]

ugh...

Euro


Canadian

GFS

NOGAPS

Ukmet