ATL: EMILY - Remnants

[tolakram]

Can an "open wave" have an LLC?

Look at the last few frames, or better yet go back 20 frames, speed it up, and observe how the LLC starts to elongate and lose definition.

http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... ite=GOES-E CONUS&lat=16&lon=-70&info=vis&zoom=1&width=1024&height=768&type=Animation&quality=90&numframes=25&map=latlon

[Bocadude85]

Looks like convection is trying to cover the llc

http://wwwghcc.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20CONUS&lat=16&lon=-70&info=vis&zoom=1&width=1024&height=768&type=Animation&quality=90&numframes=5&map=latlon

[drezee]

Can an "open wave" have an LLC?

Look at the last few frames, or better yet go back 20 frames, speed it up, and observe how the LLC starts to elongate and lose definition.

http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... ite=GOES-E CONUS&lat=16&lon=-70&info=vis&zoom=1&width=1024&height=768&type=Animation&quality=90&numframes=25&map=latlon

That is just the pull of the vertical motion of the increased convection. Fluid Dynamics and Angular Momentum, baby! Convection is trying to suck the center in...

[lebron23]

I assume things will change when it either makes it north of hait, or the western carib.

[Hylian Auree]

Emily is such a hilarious system imo. Like, I don't even know what it's doing anymore. It's just racing toward the west with convection trying to keep up xD

[5KOVERLIBOR]

I'm with you SoupBone ... I get how a lack of vertical instability can inhibit tropical cyclone development. I'd be curious to know what is the CAUSE of the lack of instability. Weak MJO signal? Nonstop shear? A lack of high pressure? Volatile upper-level winds from different directions? A combination of any of all of these?

Hey Soup, Port, others

This is the site that maintains the Vertical Instability measurements

http://www.ssd.noaa.gov/PS/TROP/TCFP/atlantic.html

The matrix is located at the bottom of the page.

This is the definition for the observation I posted:
"VERTICAL INSTABILITY: The vertical average temperature difference between the equivalent potential temperature of a parcel lifted from the surface to 200 hPa, and the saturation equivalent potential temperature of the environment, for each 5° by 5° sub-region."

I am not a professional scientists by any stretch of any imagination. I'm a low-life financial market trader - energy commodity futures specifically - and thus have an obligation to do my best to understand the threats posed by the tropics. I offer my explanation with the strong caveat to seek better, more informed, explanations (hopefully I can goose one or two out of the board here).

Vertical instability is simply the temperature gradient from the surface to some higher height in the atmosphere - here 200 hPa or MBs - really high. Convection requires a vertical lapse rate - as a parcel of air will rise until it meets its ambient temperature. If the lapse rate isn't particularly steep, as it is in this situation, the propensity for parcels of air to shoot through the atmosphere (a fundamental condition for tropical development) is low.

My opinion, likely stated as fact: Remember, weather is just Mom Nature perpetually attempting the impossible: to balance the global heat imbalance. Tropical cyclones are one of the most efficient mechanisms in which she does this. If there isn't much heat imbalance to balance...then there isn't much opportunity for these mechanisms to really fire, all else equal.

Current readings in the Caribbean indicate a temperature gradient that is normal for May - not early August. So, as I believe I see it, the convective opportunity is akin to May, not August.

Why is this happening? I have no idea. None. It just tells me that the upper portions of the atmosphere are warmer than they normally are - defining a relatively muted heat imbalance from surface to, in this observation, 200 millibars.

Again, this is how I see it. I invite anyone to pick this apart as I believe this to be a very large reason we've seen limited excitement (not quantity, but quality - i.e. strength per storm) in the tropics in 2010 and thus far this early season.

[wzrgirl1]

Can someone repost the map of Haiti and Hispanoila with the Terrain? I can't seem to locate it. Thanks!

[drezee]

URNT15 KNHC 031720
AF306 0805A EMILY HDOB 06 20110803
171030 1827N 06659W 5494 04950 0088 -017 //// 092015 015 /// /// 05
171100 1828N 06702W 5495 04961 0098 -022 //// 102014 014 /// /// 05
171130 1829N 06704W 5494 05026 0173 -020 //// 097014 015 /// /// 05
171200 1830N 06707W 5491 05038 0171 -020 //// 101014 014 /// /// 05
171230 1829N 06709W 5498 05051 0199 -016 //// 102012 013 /// /// 05
171300 1829N 06709W 5498 05051 0242 -015 //// 115014 016 /// /// 05
171330 1827N 06714W 5495 05121 0251 -015 //// 112016 020 /// /// 05
171400 1826N 06717W 5494 05128 0252 -015 //// 130023 023 /// /// 05
171430 1826N 06720W 5495 05122 0254 -011 //// 142021 022 /// /// 05
171500 1826N 06720W 5495 05122 0254 -013 //// 146022 023 /// /// 05
171530 1824N 06725W 5494 05122 0255 -014 //// 147021 022 /// /// 05
171600 1823N 06727W 5494 05129 0256 -012 //// 128015 016 /// /// 05
171630 1822N 06730W 5494 05127 0254 -015 //// 125013 016 /// /// 05
171700 1821N 06732W 5495 05125 0256 -015 //// 132011 013 /// /// 05
171730 1820N 06735W 5495 05126 0255 -015 //// 140014 014 /// /// 05
171800 1820N 06737W 5495 05128 0255 -015 //// 135012 013 /// /// 05
171830 1819N 06740W 5494 05131 0254 -018 //// 114010 012 /// /// 05
171900 1818N 06742W 5494 05125 0255 -019 //// 099009 009 /// /// 05
171930 1817N 06745W 5494 05123 0254 -018 //// 095010 010 /// /// 05
172000 1816N 06747W 5495 05125 0254 -013 //// 099007 008 /// /// 05
$$
;

[Clint_TX]

Gotta keep an eye on all of them....a little history of Andrew:

Satellite images suggest that Andrew produced deep convection only sporadically for several days, mainly in several bursts of about 12 hours duration. Also, the deep convection did not persist. Instead, it was stripped away from the low-level circulation by the strong southwesterly flow at upper levels. Air Force Reserve unit reconnaissance aircraft investigated Andrew and, on the 20th, found that the cyclone had degenerated to the extent that only a diffuse low-level circulation center remained. Andrew's central pressure rose considerably (Fig. 2 [87K GIF]). Nevertheless, the flight-level data indicated that Andrew retained a vigorous circulation aloft. Wind speeds near 70 kt were measured at an altitude of 1500 ft near a convective band lying to the northeast of the low-level center. Hence, Andrew is estimated on 20 August to have been a tropical storm with 40 kt surface winds and an astonishingly high central pressure of 1015 mb (Figs. 2 and 3 [87K GIF]).

From TPC

[drezee]

URNT15 KNHC 031730
AF306 0805A EMILY HDOB 07 20110803
172030 1815N 06750W 5496 05124 0251 -011 //// 089006 007 /// /// 05
172100 1815N 06753W 5494 05119 0253 -015 //// 018002 003 /// /// 05
172130 1814N 06755W 5496 05123 0253 -018 //// 350005 005 /// /// 05
172200 1813N 06757W 5495 05126 0254 -013 //// 000005 006 /// /// 05
172230 1812N 06800W 5493 05129 0255 -016 //// 343007 007 /// /// 05
172300 1812N 06803W 5495 05127 0255 -015 //// 347008 009 /// /// 05
172330 1811N 06805W 5494 05128 0256 -015 //// 350008 009 /// /// 05
172400 1811N 06808W 5495 05128 0257 -016 //// 335009 010 /// /// 05
172430 1810N 06810W 5494 05131 0259 -015 //// 339010 011 /// /// 05
172500 1810N 06813W 5495 05129 0258 -014 //// 345009 010 /// /// 05
172530 1809N 06815W 5495 05128 0258 -011 //// 002011 012 /// /// 05
172600 1809N 06818W 5492 05131 0256 -011 //// 066009 010 /// /// 05
172630 1808N 06821W 5495 05127 0256 -010 //// 097012 013 /// /// 05
172700 1808N 06823W 5496 05121 0255 -010 //// 098013 013 /// /// 05
172730 1807N 06826W 5495 05119 0254 -008 //// 117015 016 /// /// 05
172800 1807N 06829W 5493 05120 0253 -006 //// 119015 016 /// /// 05
172830 1806N 06831W 5499 05121 0254 -006 //// 134014 015 /// /// 05
172900 1806N 06834W 5501 05121 //// -003 //// 096016 021 /// /// 05
172930 1805N 06836W 5501 05124 //// -007 //// 088027 029 /// /// 05
173000 1805N 06839W 5486 05141 0260 -012 //// 106026 029 /// /// 05
$$

[Weatherboy1]

It seems clear at this point that Emily is going to miss the island of Hispanola, which would normally be bullish for development. But that shear is proving to be a bit of a killer. Hmmm. If she survives the night, I'm thinking this could be more of a Florida threat than most were presuming a day ago.

[OuterBanker]

I meant that it could become an open wave. And I remember the TS that hit NC a few years ago. The llc went right over us, beautiful sunny day and you could see the rotating clouds. Not a drop of rain, the rain was in the Wilmington area a hundred miles or so from the center.

[Nimbus]

This is the second time Emily has gone streaking. There is obviously still a low level circulation racing west that will miss Haiti. Convection starting to fire over the center again but there is still shear in the Easterlies. Not sure what the pressure gradient looks like but she has only gone a few hours without convection.

NHC is probably going to wait before commenting. Maybe something in the 5PM teletype?

[Shuriken]

Emily is no more than an open wave at this point.

It has a very obvious closed and perfectly circular LLC on visible satellite; it is not an open wave.

My unofficial forecast is for Emily to track over Jamaica, intensify rapidly in the northwestern Caribbean, and become a dangerous Gulf of Mexico hurricane.

[underthwx]

http://www.usno.navy.mil/NOOC/nmfc-n/RS ... wtnt01.gif


U.S Navy graphic.

[Frank2]

Late yesterday morning it looked to be forming an eye, and now it has an exposed LLC with convection mostly far removed from the center - the old NHC thinking was that once the LLC becomes exposed, the chance of it regaining it's former status was fairly low...

It might not make much sense but in reality it does seem true and has happened many times over the years, for reasons not fully understood...

Frank

[hurr123]

Emily seems to be moving more westward than expected, and each time the center becomes exposed, then it seems that stronger convection builds to save this system. Don and Emily certain have been strange storms; but, each year, their seems to be one or two that behave this way.

[OuterBanker]

Btw, Cycloneye looks like you guys have been dumped on for some time.

Is the ark ready?

[Hurricaneman]

Gotta keep an eye on all of them....a little history of Andrew:

Satellite images suggest that Andrew produced deep convection only sporadically for several days, mainly in several bursts of about 12 hours duration. Also, the deep convection did not persist. Instead, it was stripped away from the low-level circulation by the strong southwesterly flow at upper levels. Air Force Reserve unit reconnaissance aircraft investigated Andrew and, on the 20th, found that the cyclone had degenerated to the extent that only a diffuse low-level circulation center remained. Andrew's central pressure rose considerably (Fig. 2 [87K GIF]). Nevertheless, the flight-level data indicated that Andrew retained a vigorous circulation aloft. Wind speeds near 70 kt were measured at an altitude of 1500 ft near a convective band lying to the northeast of the low-level center. Hence, Andrew is estimated on 20 August to have been a tropical storm with 40 kt surface winds and an astonishingly high central pressure of 1015 mb (Figs. 2 and 3 [87K GIF]).
From TPC

when Andrew was 1000 miles from Miami it looked like crap, I hope Emily doesnt turn into one of those or Emily would take many people by suprise. At this point I cant see Emily organizing like that

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[clfenwi]

Plane is now descending to operational altitude, approaching the center from the northeast.