Alex Advisories

[Aquawind]

What is the normal distance the center is accurate to? 50 miles is a bunch when its only 80 miles from land.

lol..exactly..normal..I dunno if there is a normal..point is it's rather ill defined and elongated imho..it looks threatening ATM but has some work ahead in the organization department..sitting stationary will give it the time for Alex to develop his organizational skills..

[Brent]

Tropical Depression One Discussion Number 4


Statement as of 11:00 am EDT on August 01, 2004



the depression continues to have an ill-defined and elongated center
with multiple swirls. The Air Force reserve unit reconnaissance
aircraft did fix a center south of the previous advisory and closer
to the deep convection. This could indicate that the depression
may be starting to organize a bit...or they could have fixed a
transient feature. The official center position is relocated a
little south of the previous track but based on the overall
satellite appearance I am not going all the way down to the fix
location. The aircraft did report flight-level winds of 33 and 36
kt...with a visual surface estimate of 30 kt...and these
observations are the basis of raising the initial intensity to 30
kt. There is currently very little wind to the north or west of
the center.
Water vapor imagery indicates strong upper-level northeasterly flow
and subsidence over the northern part of the depression's
circulation...which should hinder significant strengthening of the
tropical cyclone. However...upper-level southwesterlies are headed
toward the cyclone...and as the flow transitions the depression may
find a briefly more favorable upper pattern in 24 hours or so. The
SHIPS guidance brings the depression to near 50 kt in 36
hours...while the GFDL shows little change. The official forecast
roughly splits the difference and has the system as a tropical
storm very close to the coast in 24 hours. As a result...a Tropical
Storm Warning is required at this time. Later in the forecast
period...global model guidance shows the cyclone merging with a
larger extratropical low pressure system.

Given the ragged nature of the circulation...the initial motion is
hard to determine...but appears to be essentially stationary. The
depression is approaching a break in the subtropical ridge...so
steering currents are weak and the cyclone is forecast to move
rather slowly and remain near the south and North Carolina coasts
through 36-48 hours. Thereafter...a gradually amplifying mid-level
trough is likely to carry the tropical cyclone northeastward with
an increase in forward speed. The official track forecast is fairly
similar to the previous advisory. If the depression is in fact
reorganizing farther south...then the current forecast is likely to
be too fast.

Forecaster Franklin

forecast positions and Max winds

initial 01/1500z 31.9n 79.2w 30 kt
12hr VT 02/0000z 33.0n 78.8w 30 kt
24hr VT 02/1200z 34.1n 77.8w 35 kt
36hr VT 03/0000z 35.1n 76.2w 40 kt
48hr VT 03/1200z 36.5n 74.0w 40 kt
72hr VT 04/1200z 41.0n 66.0w 40 kt
96hr VT 05/1200z 46.0n 56.0w 40 kt...extratropical
120hr VT 06/1200z...absorbed by extratropical low

[The Dark Knight]

Your right Dixiebreeze, almost but, not just yet!!!....

[Derecho]

It's actually about 7 kts away (flight level) from TS, which is fairly far.

And the NHC Discussion was not very enthusiastic about it....far less so than this board.

This is still very much a badly sheared, poorly organized storm.

[wharrell]

Check the visible. The disorganized center is actually north of the cloud shield which is typical in a sheared system.

http://www.ssd.noaa.gov/PS/TROP/DATA/RT/float-vis-loop.html

[dixiebreeze]

http://iwin.nws.noaa.gov/iwin/sc/hurricane.html

[Rieyeuxs]

As somebody who's sitting here at the beach, it's not worth writing home about it yet...

[Stormsfury]

As somebody who's sitting here at the beach, it's not worth writing home about it yet...

The only real threat to us in the Charleston area are potentials for heavy rainfalls ... but with the setup, and structure of #1, we may not get hardly anything at all ... take note though, IF something down the road takes a similar path and it much better organized ... a system 80 miles SSE of Charleston bares a huge problem later in the season, should this occur.

SF

[wxman57]

Here's a shot from a few hours ago, showing 3 vortices rotating around a large ring north of the convection. The most well defined vortex just moved north out of the area of convection and is (was) heading northward:

http://myweb.cableone.net/nolasue/alex3.gif

That vortex is now heading westward and will soon turn southwestward as it rotates counter-clockwise. I can now see another eddy on the SC coast that's moving southward.

Clearly, the "depression" is in a state that would not generally qualify for upgrading to TD status, but the NHC won't downgrade it since it's near the coast. Wind shear remains high, but there may be a brief period tonight when the wind shear shifts from NE to SW when the shear may relax enough for some squalls to build northward closer to the center (before the squalls shift to the NE-E quadrant tomorrow).

All it'll take is one FL wind of 40-45kts for them to upgrade it. That could easily happen in that area of squalls, so we can't rule out this becoming Alex, even though it doesn't have a well-defined circulation.

[Stormsfury]

I noted such a swirl on IR2 while in chat last night NNE of the convection. Clearly, while in this state, any intensification the does occur will be very slow to occur.

Currently, there isn't much wind at all NW of Charleston, but we are reporting a heavy shower.

SF

[Stormchaser16]

Any strengthening should be very slow to occur with 3 defined vortices spinning NORTH of any convection. Although if the one moving SEwrd can mvoe under the convection then it may takeover the other circs. and develop into a TS.

[hurricanemike]

wxman,

Where did u get the sat/sfc data composite from?

[Stormsfury]

wxman,

Where did u get the sat/sfc data composite from?

Mike, I think he has McIdas, and is able to create his own.

[wxman57]

Here's a new image. Two vortices rotating W-NW, one coming south down the SC coast:

http://myweb.cableone.net/nolasue/alex4.gif

[Stormchaser16]

000
URNT12 KNHC 011452
VORTEX DATA MESSAGE
A. 01/1450Z
B. 31 DEG 41 MIN N
78 DEG 58 MIN W
C. NA
D. 25 KT
E. 034 DEG 111 NM
F. 165 DEG 30 KT
G. 035 DEG 118 NM
H. EXTRAP 1010 MB
I. 24 C/ 299 M
J. 25 C/ 298 M
K. 23 C/ NA
L. NA
M. NA
N. 1345/1
O. 0.5/5.0 NM
P. AF861 0401A CYCLONE OB 09
MAX FL WIND 33 KT SW QUAD 1236Z. SLP EXTRAP FROM 1500FT.

For those who are interested and have not yet seen it

[wxman57]

wxman,

Where did u get the sat/sfc data composite from?

No, I'm using GARP/GEMPAK to make the images, but let me see if remember my McIdas coding and vi editing.

[Brent]

That was at 10:50am ET right?

Next recon flight is scheduled for 18z(I'm assuming that is when it leaves, meaning it'll be an hour or so later before they get there).

[DerekOrtt]

Finally have been able to log in under a different name (or should I say, a similar name)

storm updates in addition to forecasts are at http://www.nwhhc.com/atl012004.html

I am unable to make graphics at least for a while (until tomorrow at the earliest)

Also, my rsmas e-mail is also down for a while. so dont try to e-mail me there today

[Stormsfury]

Thanks, Stormchaser16. 33 kt FL winds isn't wouldn't even come close to upgrading this right now. There's hardly any wind here (only some occasional breezes to 15 mph), but just had a very heavy rain shower that dumped ½" of rain in just 15 minutes .. some of the cells are developing into thunderstorms. A couple of thunder rolls have just occurred in the last two minutes.

SF

[Brent]

Here's a new image. Two vortices rotating W-NW, one coming south down the SC coast:

http://myweb.cableone.net/nolasue/alex4.gif

Which center is the one the NHC used at 11am?