ATL: INVEST 99L - Discussion

[Weatherwatcher98]

Saved loop showing exposed LLC moving N just north of the Yucatan:

Very broad area. Looks like a few swirls in the area. That appears to be the dominant one though.

[Weatherwatcher98]

Nice little blow up nne of the Low I am watching

[stormlover2013]

Just good ole rain my peeps, wind sheer is horrendous, the ingridents just isn't there

[tropicwatch]

Looks like the ull close to Texas is moving north and some movement back towards the west this might give 99L some breathing room.

[Hammy]

Looks very late fall/early winter right now. Good chance of heavy rain here in northern Georgia?

[Dean4Storms]

Mobile, AL NWS Afternoon Discussion.....


AT THE SURFACE...A MUCH MORE COMPLEX PATTERN EXISTS. A WEAKLY DEFINED
SURFACE PRESSURE TROF/LOW WAS ANALYZED OVER THE NORTHWEST GULF...OFF
THE UPPER TEXAS/SOUTHWEST LOUISIANA COAST UNDER THE UPPER LEVEL
LOW. THE OTHER EXISTS OVER THE SOUTH CENTRAL GULF. LATEST VISIBLE
SATELLITE DATA SHOWS A LOW LEVEL CLOUD SWIRL ASSOCIATED WITH A WEAK
SURFACE LOW ABOUT 100 MILES NORTHWEST OF CANCUN MEXICO. WITH THE
PRESENCE OF THE UPPER LOW OVER THE WESTERN GULF...DEEP LAYER H70-H30
BULK SHEAR IS VERY HIGH...RANGING FROM 30 TO 50 KNOTS. THIS IS A VERY
HOSTILE SETUP FOR TROPICAL DEVELOPMENT OF THE SOUTHERN GULF SURFACE
LOW...WITH SHOWERS/STORMS WELL REMOVED AND TO THE EAST OF THE CENTER
OF CIRCULATION. DESPITE THE STRONG UPPER LEVEL WINDS...THERE IS A LOW
CHANCE THAT THE SURFACE LOW PRESSURE LIFTING NORTHWARD ACROSS THE
CENTRAL GULF THROUGH MONDAY WILL DEVELOP. FORECASTERS WILL CONTINUE
TO MONITOR. REGARDLESS...THE MAIN IMPACTS REMAIN THE POTENTIAL FOR
HEAVY RAIN AND LOCALIZED FLOODING AS LARGE SCALE ASCENT FROM A
DIFFLUENT HIGH LEVEL FLOW AND ABOVE NORMAL DEEP LAYER MOISTURE
CONTINUES TO BE PUMPED NORTHWARD IN OFF THE GULF. RADAR
PRECIPITATION ESTIMATES OVER THE LAST FEW HOURS HAVE ALREADY SHOWN
THAT THE PASSAGE OF SOME OF THE HIGHER REFLECTIVITIES HAS RESULTED
IN UPWARDS OF 3 TO 4 INCHES OF RAIN LOCALLY AND GENERALLY OVER
DAUPHIN ISLAND AND SOUTHERN MOBILE COUNTY. HERE IS A LOOK AT THE
GENERAL RANGE OF LOCAL FLASH FLOOD GUIDANCE VALUES ACROSS OUR AREA:

1HR- 3 TO 5 INCHES
3HR- 4 TO 6 INCHES
6HR- 5 TO 7 INCHES

[Dean4Storms]

Well that swirl is clearly not an eddy!

[blp]

Swirl looks to be moving NNE now. If it can move NE or ENE to get closer to the deep it has its best chance against the shear.

http://www.ssd.noaa.gov/PS/TROP/floater ... imated.gif

[gatorcane]

There appears to be an area of slightly lowering shear across the SE GOM. But 99L is supposed to head north into the increasing shear across the Central and Northern GOM:

[gatorcane]

Here is a short IR floater. Three things I see: the LLC north of the Yucatan is wobbling to the NE. It appears that 99L is trying to wrap a new band of T-storms/convection over the NE/N side of the LLC. Finally, the high clouds racing to the NE to the WNW of 99L appear to have gradually slowed down some and are moving more NNE instead of NE. This suggests shear might be decreasing just a tad over 99L it appears.

[NDG]

Well that swirl is clearly not an eddy!

I can clearly still see that there are still 2 eddies rotating around each other, there's no LLC other than a broad circulation overall.

http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... mframes=30

[Dean4Storms]

Yes, looks like just 50-75 miles to the East the shear is a good bit less. If this LLC moves eastward at all it could be in a more favorable environment. Have to watch it!

[gatorcane]

Looping this loop, seems a pretty clear wobble NE unless it is just a vorticity that will just fade away, or like NDG pointed out, it is just rotating around a broad circulation.

http://www.nrlmry.navy.mil/nexsat-bin/n ... PE=Instant

[Dean4Storms]

Well that swirl is clearly not an eddy!

I can clearly still see that there are still 2 eddies rotating around each other, there's no LLC other than a broad circulation overall.

The small eddy has been rotating around the LLC as you would expect. But that LLC is clearly just moving northward.

The NWS is calling it the Low so I have no problem calling it the LLC as it certainly is a low level circulation. Nobody is calling it a closed surface circulation.

Come on NDG.

[Weatherwatcher98]

Yes, looks like just 50-75 miles to the East the shear is a good bit less. If this LLC moves eastward at all it could be in a more favorable environment. Have to watch it!

25-85 has been what Has been catching my attention

[NDG]

Well that swirl is clearly not an eddy!

I can clearly still see that there are still 2 eddies rotating around each other, there's no LLC other than a broad circulation overall.

The small eddy has been rotating around the LLC as you would expect. But that LLC is clearly just moving northward.

The NWS is calling it the Low so I have no problem calling it the LLC as it certainly is a low level circulation. Nobody is calling it a closed surface circulation.

Come on NDG.

http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... mframes=30

[gatorcane]

You can see two swirls there rotating around a broader circulation. Nice loop NDG!

[NDG]

Looks like the ull close to Texas is moving north and some movement back towards the west this might give 99L some breathing room.

And you can see the shear knocking that area of convection away from the surface low already.

[Dean4Storms]

Looping this loop, seems a pretty clear wobble NE unless it is just a vorticity that will just fade away, or like NDG pointed out, it is just rotating around a broad circulation.

http://www.nrlmry.navy.mil/nexsat-bin/n ... PE=Instant

It has been there since this morning moving northward and that is where the NHC and NWS have been stating the Low is positioned. I do see the slight movement NNE maybe and I also see convection beginning to fire to the North of it in a band swirling into it.

[caneman]

Agreed it's an llc, not just an eddy. Devoid of convection though. If it got up under the convection might be a bit of a different story.