ATL: Tropical Depression Fay

[Honeyko]

The tag-team killers:

http://www.ssd.noaa.gov/goes/east/carb/loop-wv.html
http://www.nlmoc.navy.mil/cgi-bin/movie ... tlantic+wv
http://www.ghcc.msfc.nasa.gov/GOES/goeseastnhewv.html

Rock-mode (if available), speed fast.

See ULL at 27N longitudinally-aligned with 92L, and the front off the east coast with zone of divergence aloft to the west of the ULL? -- Note the exhaust from the front's convective region streaming in a broad veil to the southeast, where it sinks in front of and north of 92L.

This is how a strong east-coast trough can cripple or snuff a tropical system while it's still over a thousand miles away.

[Ed Mahmoud]

Dry air is having some limited impact on the system.

The orange and red areas you're seeing are subsiding air. Note the strongest subsidence is right in front of 92L, not over toward Africa (where the SAL should presumably be driest).

Subsidence = adiabatic warming = capping layer. Less lift, less condensation, less clouds, certain light wavelengths bounce or radiate from the ocean surface straight to the satellite without hitting a thing.

Inter related, but I don't think there is a strict cause and effect between dry air and subsidence. One can produce the other, I believe, but dry air can exist independent of subsidence. I could be wrong, not a pro.

Note, BTW, a couple of convective cells in the heart of the dry air near 55ºW

[alan1961]

i am really wondering why the GFS still doesn't pick up this system

the gfs picks it up as a weak system mecklenburg and really keeps it as a weak storm too, at the moment thats all it is, if it stays as a weak system thru the islands then the gfs will be right, if it ends up being a, say cat 1 or 2 cane it would probably be a bit out, simple as that really.

[HURAKAN]

TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT SUN AUG 10 2008

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

A BROAD AREA OF LOW PRESSURE ASSOCIATED WITH A TROPICAL WAVE IS
LOCATED OVER THE CENTRAL ATLANTIC OCEAN ABOUT 1000 MILES EAST OF
THE WINDWARD ISLANDS. ALTHOUGH ASSOCIATED SHOWER AND THUNDERSTORM
ACTIVITY HAS DECREASED THIS EVENING...ENVIRONMENTAL CONDITIONS
APPEAR FAVORABLE FOR GRADUAL DEVELOPMENT...AND THIS SYSTEM HAS THE
POTENTIAL TO BECOME A TROPICAL DEPRESSION DURING THE NEXT COUPLE OF
DAYS AS IT MOVES WESTWARD AT 15 TO 20 MPH.

AN AREA OF DISTURBED WEATHER IS LOCATED OVER THE CENTRAL ATLANTIC
OCEAN ABOUT 700 MILES WEST-SOUTHWEST OF THE CAPE VERDE ISLANDS.
THIS SYSTEM HAS NOT BECOME ANY BETTER ORGANIZED DURING THE DAY AND
DEVELOPMENT...IF ANY...OF THIS SYSTEM SHOULD BE SLOW TO OCCUR
DURING THE NEXT COUPLE OF DAYS AS IT MOVES WESTWARD AT ABOUT 15
MPH.

ANOTHER AREA OF SHOWERS AND THUNDERSTORMS...ASSOCIATED WITH A
TROPICAL WAVE...IS LOCATED A COUPLE HUNDRED MILES SOUTH OF THE CAPE
VERDE ISLANDS OVER THE EASTERN ATLANTIC OCEAN. ENVIRONMENTAL
CONDITIONS COULD FAVOR SOME SLOW DEVELOPMENT OF THIS SYSTEM AS IT
MOVES WESTWARD AT ABOUT 15 MPH.

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

$$
FORECASTER BLAKE

[RL3AO]

Plan of the day will probably include a "possible fix" in the succeeding day outlook when its next issued.

[HURAKAN]

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT SUN AUG 10 2008

...SPECIAL FEATURES...
A BROAD AREA OF LOW PRESSURE IS ASSOCIATED WITH AN ATLANTIC
OCEAN TROPICAL WAVE THAT IS ALONG 42W/44W SOUTH OF 18N.
THE LOW CENTER IS NEAR 11N. ISOLATED MODERATE SHOWERS TO
LOCALLY STRONG THUNDERSTORMS ARE FROM 8N TO 16N BETWEEN 38W
AND 47W. ASSOCIATED SHOWER AND THUNDERSTORM ACTIVITY HAS BEEN
INCREASING SLOWLY DURING THE LAST 24 HOURS...AND CONDITIONS
APPEAR SOMEWHAT FAVORABLE FOR GRADUAL DEVELOPMENT OF THIS SYSTEM
DURING THE NEXT COUPLE OF DAYS AS IT MOVES WESTWARD 15 TO 20 MPH.

[HURAKAN]

[storms in NC]

Looks horrible, someone hit the off switch. Looks like my ability to destroy storms by predicting development is still working. ..

Quite to the contrary, it looks quite healthy to me. I think convection will re-fire tonight and we'll have a TD by sometime tomorrow.

I too think the same way. It seem to me that they do this as the are building up.

[alan1961]

according to the gfs the second area as got to bomb a bit in the next few days to play out the gfs model, as a poster said earlier it may be having some of its moisture sucked out of it by invest 92L.

[wzrgirl1]

i definitely think we have a contender here folks. Of course we must wait for it to be upgraded, but I hope it stays minimal for the islands sake.

[cycloneye]

Red:

[AJC3]

Elongated, but still a pretty decent circulation on the late afternoon QS pass...

[wzrgirl1]

oh boy we are in the red zone....that's not good...the three waves seem so close together but i wonder how close they really are as far as miles go

[HURAKAN]

Red:

The train is heading west.

[Derek Ortt]

definite closed circulation

[stormchazer]

definite closed circulation

All it needs is to build some convection and it would likely get classified eh?

[Derek Ortt]

yeah... even despite the convergence

I said in the nwhhc outlook this this could become a depression tomorrow

[RL3AO]

It we get some strong convection over the center, we might have a TD at 5am or 11am.

[HURAKAN]

It we get some strong convection over the center, we might have a TD at 5am or 11am.

11 am seems right if we get some strong convection over the center. The NHC almost exclusively waits for visible when the system is not close to land where it can be tracked by radar and/or RECON.

[HURAKAN]