Atlantic Tropical Action 2014

[wxmeddler]

92L is certainly not giving up without a fight... nice mesocyclone in the current cluster of strong cells over FL.

 

Yup, perfectly cyclonic windfield on the surface stations around it too. The nearest sfc pressure reading to the "center" is 1011.9 is by a South Florida Water Management District Mesonet station.

[Srain]

The overnight reliable guidance.suggests 92L will continue traveling W across the Gulf and will be S of Louisiana on Tuesday beneath a mid level ridge S of a stalled frontal boundary. The Euro and GFS keep this disturbance weak, but interestingly the HWRF is now a bit more aggressive and suggests a 45kt Tropical Storm nearing the Middle Texas Coast in Wednesday. The TVCN agrees with a movement toward Coastal Texas as a stalled boundary lingers along or just S of the I-10 Corridor before washing out. The medium range guidance suggests a short wave will move across the Southern Plains late Wednesday into Thursday and drop a frontal boundary into Texas. Mid/upper level moisture associated with EPAC Odile will continue spreading across Northern Mexico and additional tropical moisture from the Caribbean looks to pool across the Western Gulf as well.

[Kory]

The overnight reliable guidance.suggests 92L will continue traveling W across the Gulf and will be S of Louisiana on Tuesday beneath a mid level ridge S of a stalled frontal boundary. The Euro and GFS keep this disturbance weak, but interestingly the HWRF is now a bit more aggressive and suggests a 45kt Tropical Storm nearing the Middle Texas Coast in Wednesday. The TVCN agrees with a movement toward Coastal Texas as a stalled boundary lingers along or just S of the I-10 Corridor before washing out. The medium range guidance suggests a short wave will move across the Southern Plains late Wednesday into Thursday and drop a frontal boundary into Texas. Mid/upper level moisture associated with EPAC Odile will continue spreading across Northern Mexico and additional tropical moisture from the Caribbean looks to pool across the Western Gulf as well.

The NHC usually likes to model their track after the TVCN, or the consensus of the models. So if this were to be declared and have a forecast track, it'd look like the TVCN. If you look closely, it looks like the TVCN slows down toward the end and is showing signs of bending back N and possibly NE.

[Kory]

According to surface wind reports, it looks like the surface low is just east of Belle Glade, FL.  Lowest pressure I've found was 29.88 inches or 1011 mbars.  

[Srain]

To further complicate matters, a surface low is developing in the Bay of Campeche via buoy data and surface observations.

 

[Kory]

Some 12z runs for 92L.  Majority are showing some sort of recurve back to the NE. 

 

[IsentropicLift]

Could we be getting another center relocation? Looks like some spinning on radar near Key West.

 

http://radar.weather.gov/radar.php?product=NCR&rid=byx&loop=yes

 

That spinning is right under where the latest burst of convection is taking place

 

[GaWx]

The 18Z GFS had a weak version of this, but the 0Z GFS went back to the sig. TC Gulf coast hit for ~9/20-1 fwiw (6 of 7 runs). The Euro runs have still not yet shown this landfalling north GoM TC through the 12Z run of THU.

The 6z GFS has a TC landfall on the NE gulf coast on 9/22, i.e., delayed about a day from those 6 of

7 GFS runs with a 9/20-1 hit. If this 6z run is counted, that would make 7 of 8 of the last GFS runs with a US gulf coast hit during the 9/20-2 period fwiw.

Edit: should there be a separate thread created for 92-L?

[Srain]

The 6z GFS has a TC landfall on the NE gulf coast on 9/22, i.e., delayed about a day from those 6 of

7 GFS runs with a 9/20-1 hit. If this 6z run is counted, that would make 7 of 8 of the last GFS runs with a US gulf coast hit during the 9/20-2 period fwiw.

Edit: should there be a separate thread created for 92-L?

If a TD/TS is declared, there will be a pinned thread for it.

[IsentropicLift]

Is this the system that the long range GFS had been developing last week?

 

[Kory]

Could we be getting another center relocation? Looks like some spinning on radar near Key West.

http://radar.weather.gov/radar.php?product=NCR&rid=byx&loop=yes

That spinning is right under where the latest burst of convection is taking place

Surface obs still support a surface low NE of the Bell Glade area. I don't see anything to support a surface circulation down there.

[IsentropicLift]

Surface obs still support a surface low NE of the Bell Glade area. I don't see anything to support a surface circulation down there.

SPC meso analysis shows the low over Florida but you can see some spinning near Kew West as well, maybe not a closed circulation but some resembelence of cyclonic winds.

 

[MarkSC]

This is going to be a fun one to track if the east turn in the Gulf occurs like some models are forecasting. Development chances look to improve if that turn occurs.

[GaWx]

Some 12z runs for 92L. Majority are showing some sort of recurve back to the NE.

Even the Euro hints at this. After having the surface low hit S/C TX on 9/17, it suggests much of the 92-L moisture/energy making a sharp turn toward the ENE as the 500 mb winds near 92L switch from an easterly component to WSW as the long wave 500 mb trough gets further down in the SE US. So, the WSW upper level winds seem to then take much of the moisture/energy ENE late next week even with the intact sfc low no longer existing on the 0z Euro after it hits TX.

[Kory]

SPC meso analysis shows the low over Florida but you can see some spinning near Kew West as well, maybe not a closed circulation but some resembelence of cyclonic winds.

It looks like that may be a mid level circulation as the 500 mbar vorticity is SSW of the 850 and 700 mbar vorticity. Looks elongated and very disorganized.

[Srain]

The cckw continues to progress E. It appears the ensemble means were correct last week when they were suggesting lowering pressures and a potential unsettled pattern developing in the Western Caribbean and the Gulf in the mid September timeframe.

 

[Superstorm93]

Surprise?

[IsentropicLift]

Surprise?

Plenty of global model runs have been developing that wave for over a week. NHC made it a lemon this morning.

[Superstorm93]

Plenty of global model runs have been developing that wave for over a week. NHC made it a lemon this morning.

It's looking very well organized this morning. There's more than likely a LLC just by looking at the cloud pattern and the upper-level cirrus indicates a relatively decent shear profile. First storm-specific models take this generally West and gradually strengthen it to near Hurricane strength. Could be interesting due to the fact that the CCKW should aid in development/intensification down the line.

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[Superstorm93]

AOI in the BOC appears to be organizing rather quickly. 

 

[Kory]

A potential monkey wrench into 92L's future could be the ULL that is to it's east enhancing the northerly shear.  If that continues to move westward along with 92L (into the Gulf of Mexico), you can stick a fork in him...

 

[wxmx]

AOI in the BOC appears to be organizing rather quickly. 

 

 

They always do...but there's just too  much shear and < 24 hours before land interaction. Has the perfect track and timing to interact with our first weak cold front and orographic moisture fetch. Raw GFS output bullseyes my region with 5-8"

[bluewave]

North of 25N seems like the dividing line for getting a hurricane in the Atlantic this 

season north of the very dry and stable air.

 

[wxmx]

92L is now bare naked...maybe it can pull a Dolly and reform near the convection around the westernmost keys. Latest ASCAT shows a tiny and weak area of cyclonic winds there.

[Kory]

Shear has been increase down in the Bay of Campeche, so it should keep that system in check.  Not to mention, it will be moving NW into land within 24-36 hours.  

 

Shear has been in the decline in the Northern and Eastern parts of the Gulf.  With 92L moving at a nice clip westward, it should be out over the Gulf by the end of today.  Another caveat will be the ULL to 92L's east.  It has been enhancing shear over the Florida Peninsula and points east. 

 

[IsentropicLift]

It's the GGEM so we'll take it with a grain of salt, but we're talking track here and not intensity. The GGEM takes the lemon in the E ATL and keeps it far enough away from Edouard that the sub-tropical ridge is able to build back to it's north and the system finds itself nearing the Bahamas in about ten days with a trough swinging through the plains. It would probably end up recurving east of the US but I'm not sure that the system is a definite fish if it does indeed develop.

 

The GFS and ECMWF also develop this system but have it falling victim to influince from Edouard.

[Kory]

Recon plans for 92L...

 

1045 AM EDT FRI 12 SEPTEMBER 2014

SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)

VALID 13/1100Z TO 14/1100Z SEPTEMBER 2014

TCPOD NUMBER.....14-104

 

I. ATLANTIC REQUIREMENTS

1. SUSPECT AREA (GULF OF MEXICO)

FLIGHT ONE -- TEAL 71                              FLIGHT TWO -- TEAL 72

A. 13/1730Z                                              A. 14/1130Z, 1730Z

B. AFXXX 01HHA INVEST                            B. AFXXX 0207A CYCLONE

C. 13/1545Z                                              C. 14/0945Z

D. 26.0N 84.0W                                         D. 26.0N 87.5W

E. 13/1700Z TO 13/2200Z                          E. 14/11005Z TO 14/1730Z

F. SFC TO 10,000 FT                                  F. SFC TO 10,000 FT

 

2. OUTLOOK FOR SUCCEEDING DAY: CONTINUE 6-HRLY FIXES IF

SYSTEM DEVELOPS AND IS A THREAT

[Superstorm93]

Interesting TWO by Avila. No mention of the BOC disturbance, decreases probs for 92L, and basically writes 93L off.

Can't say I disagree with most of it...

[phil882]

Interesting TWO by Avila. No mention of the BOC disturbance, decreases probs for 92L, and basically writes 93L off.

Can't say I disagree with most of it...

 

http://rammb.cira.colostate.edu/products/tc_realtime/loop.asp?product=1kmsrvis&storm_identifier=AL932014&starting_image=2014AL93_1KMSRVIS_201409121315.GIF

 

Watch 93L get a special TWO when ASCAT confirms there is a nice surface circulation underneath that CDO. Its not surprising Avila didn't raise probabilities since he tends to be on the more pessimistic side when forecasting. 

 

The BoC disturbance and disturbance south of Bermuda probably could have lemoned for at least low probabilities. Even if its 10%, there is almost certainly a > 0 % of development with both systems given their current state of organization and model support. 

[GaWx]

The 6z GFS has a TC landfall on the NE gulf coast on 9/22, i.e., delayed about a day from those 6 of

7 GFS runs with a 9/20-1 hit. If this 6z run is counted, that would make 7 of 8 of the last GFS runs with a US gulf coast hit during the 9/20-2 period fwiw.

 

 Well, the 12Z GFS has a weaker (tropical or possibly subtropical) surface low hit the NE GoM coast on 9/22 but still causing quite wet conditions for parts of the SE US. That makes 8 of the last 9 runs with a gulf low making landfall on the N/NE GoM coast within 9/20-2.

 Who knows? If a strong version of this were to verify, this could easily turn out to be the most impactful US tropical system for the rest of the season. This seems to be coming in conjunction with an advancing CCKW per Steve and others. Also, the MJO would be pretty favorable for September genesis per GEFS/Euro ens. projections of phase 1, 2, or just within circle for then. So, late next weekend may turn out to be an interesting time. I'd like to see the Euro come on board for this before getting close to confident in a threat. Nevertheless, the GFS is already telling me to be wary for around 9/20-2.