Invest 97L: Comments, Sat Pics, Models Thread #3

[O Town]

Not liking the GFDL at all this morning.

[JBP]

Really don't like any of them. Starting to really look like someone along the gulf coast is unfortunately going to have to deal with this one eventually.

[Thunder44]

By looking at the system I will say that the National Hurricane Center will wait for the RECON plane before any upgrade. By the way, will the plane depart from St. Croix or its normal base in Mississippi?

The plane is scheduled to leave at 16z arrive by 18z, so I assume such a short flight means that they are already at St. Croix.

[Matt-hurricanewatcher]

I would place the center at 11-11.3 north/59 west. Near that big blob of convection. It appears that the flow has grown even stronger on both sides of the wave axis. We will have to wait for it to pass by those islands to find if this has a west wind. Or maybe for the recon. Nice inflow over the southern side none the less.

[oldnavyguy]

Will, you know who this is. Good morning. Posting before 4:00 PM are we? Didn't think I got up this early did we?

Two posts already? I'll take a Butterfinger please.

READ other posts for the rest of the day. Have a good Day.

[KatDaddy]

No reason to worry about this one until its into the NW Caribbean. The models will flip and flop. In addition this is only an Invest and nothing more.

[Lowpressure]

Wasn't it the GFDL that predicted Chris would fizzel then fade over DR. At that point Chris was on the verge of Cane and looked to be a SFL threat then into the GOM as a potential major. Most of us threw out the GFDL scanario, then it pretty much played out.

[KatDaddy]

Corpus Christi Forecast Disc:

SHOULD CONT TO MENTION STRONG TROPICAL WAVE LOCATED JUST E OF THE
WINDWARD ISLAND THIS MORNING AND BECOMING BETTER ORGANIZED.
GFS...ECMWF AND UKMET KEEP SYS OPEN AS A STRONG TROPICAL WAVE THRU
THE CARIBBEAN OVR THE WEEKEND AND NEAR THE YUCATAN EARLY NEXT
WEEK. CANADIAN CONTS TO INDICATE A STRENGTHENING...CLOSED SYS
MOVING INTO THE GULF ON MON. SYS IS SOMETHING TO KEEP AN EYE ON
FOR THE MID TO LATTER PART OF NEXT WEEK.

[HURAKAN]

By looking at the system I will say that the National Hurricane Center will wait for the RECON plane before any upgrade. By the way, will the plane depart from St. Croix or its normal base in Mississippi?

The plane is scheduled to leave at 16z arrive by 18z, so I assume such a short flight means that they are already at St. Croix.

Thanks.

[Thunder44]

The GFS is predicting quite a bit of shear to return to the central and western Carribean by 8pm friday. Could this put the lid on 97L?

http://weather.unisys.com/hurricane/shr_48.gif

The culprit is another nasty ULL...

http://weather.unisys.com/hurricane/3hh_48.gif

Perhaps this is why the GFDL shows a more NW movement

I saw that on the 0z GFS earlier and I'm concerned that ULL in the NW Carribean may not get out of the way for this disturbance to develop more than a TS once it reaches the Central Carribean. It may even be ripped apart. There is already 40kt to 50kt shear there this morning:

http://cimss.ssec.wisc.edu/tropic/real- ... g8sht.html

[Thatsmrhurricane]

Guess it is wait and see. The structure looks impressive. Is that a(n) outflow boundary to 97's NW?

[Matt-hurricanewatcher]

The Gfdl is pretty much the most advanced hurricane model we have...Its made for hurricanes or tropical cyclones unlike the global models like the Gfs,ECMWF,CMC(Canada),Ukmet. The Bam,Bamm,Lbar are all based off the globels. So the GFDL is pretty much number one in hurricane forecast models. Yes it has been know to bomb systems as they are weak. Thats why you don't take it to seriously now. But later on take it very seriously.

[O Town]

The Gfdl is pretty much the most advanced hurricane model we have...Its made for hurricanes or tropical cyclones unlike the global models like the Gfs,ECMWF,CMC(Canada),Ukmet. The Bam,Bamm,Lbar are all based off the globels. So the GFDL is pretty much number one in hurricane forecast models. Yes it has been know to bomb systems as they are weak. Thats why you don't take it to seriously now. But later on take it very seriously.

Thanks Matt I was about to say I thought it was the best for this type of scenerio, deep tropic cyclones. I know its only an invest now and can not be too acurate as of yet because there is no actuall LLC for it to fix off of.

[willjnewton]

does the gfdL still predicts a deep significant cyclone thats 970mb as this system moves northward.I guess??

[djones65]

Looking at surface observations and the most recent 1 km high resolution visible image taken at 1045 UTC I do not believe there is a surface circulation with 97L.
In fact, its rapid west northwestward motion is now almost 23 knots and it will be quite difficult for a surface circulation to close off in the next 12 hours or so.
Barbados reported ENE winds at 20-25 mph from 0200 until 0600 UTC. Between 0600 UTC and 0900 UTC winds were East at 30 to 35 mph. At 1000 and 1100 UTC winds shifted to ESE at 25 to 30 mph. The lowest pressure of 1009.7 mb occurred between 0700 and 0900 UTC. The pressure has risen slightly. St. Lucia has reported NE winds at 25 to 30 mph the last several hours. Tobago has reported ESE winds at 10 to 15 mph the last couple hours and pressure came up from 1010 to 1011 mb in the last hour (1100 UTC). I personally believe the ESE wind at Tobago is from a convergence line or weak "tail" extending to the southwest of 97L and is NOT indicative of the wave passage at their longitude yet (which is 61W).
However, looking closely at the 1 km visible image at 1045 UTC I see what looks like a weak vortmax (low level, but not surface) near 12.7N and 60.1W about 45 miles southwest of Barbados and 70 miles southeast of St. Lucia. There are two weak low level lines which tend to "curl" around the west side of a possible low level vorticity maximum. This is located west southwest of the main convection approaching Barbados and north of the convection over Trinidad and Tobago.

The system does not seem to be organizing right now, and probably will not for at least the next 12 hours or so. With a forward speed in excess of 25 mph it will be quite difficult to measure/observe westerly surface winds south of a low level vortmax. There is definitely a surface low pressure area in the SLP field as evidenced by the 4 mb pressure fall in Barbados during the 24 hours preceeding 0900 UTC. But I do not believe we will see Ernesto or even a depression until it can slow down over the Caribbean Sea later tonight or Friday. The BAM models slow the speed down considerably after 24 hours and that is when I believe tropical cyclone formation will be more likely. The GFDL's depiction of a northwest turn seems unlikely given the rapid forward speed at the moment.

[Steve]

>>and I'm concerned that ULL in the NW Carribean may not get out of the way for this disturbance to develop more than a TS once it reaches the Central Carribean.

Some concern, eh?

Steve

[Air Force Met]

Wasn't it the GFDL that predicted Chris would fizzel then fade over DR. At that point Chris was on the verge of Cane and looked to be a SFL threat then into the GOM as a potential major. Most of us threw out the GFDL scanario, then it pretty much played out.

The GFDL was HORRIBLE for Chris. IT dissipated it before it even got there...and the track was by far one of the worst performers. The CONU was way better...even the GFS was better.

For Chris, the GFDL was a dog.

[WeatherEmperor]

Wow. The 6Z GFDL doesnt even develop 97L anymore. Look at this graphic:
http://www.sfwmd.gov/org/omd/ops/weathe ... orm_97.gif

<RICKY>

[Matt-hurricanewatcher]

Looking at surface observations and the most recent 1 km high resolution visible image taken at 1045 UTC I do not believe there is a surface circulation with 97L.
In fact, its rapid west northwestward motion is now almost 23 knots and it will be quite difficult for a surface circulation to close off in the next 12 hours or so.
Barbados reported ENE winds at 20-25 mph from 0200 until 0600 UTC. Between 0600 UTC and 0900 UTC winds were East at 30 to 35 mph. At 1000 and 1100 UTC winds shifted to ESE at 25 to 30 mph. The lowest pressure of 1009.7 mb occurred between 0700 and 0900 UTC. The pressure has risen slightly. St. Lucia has reported NE winds at 25 to 30 mph the last several hours. Tobago has reported ESE winds at 10 to 15 mph the last couple hours and pressure came up from 1010 to 1011 mb in the last hour (1100 UTC). I personally believe the ESE wind at Tobago is from a convergence line or weak "tail" extending to the southwest of 97L and is NOT indicative of the wave passage at their longitude yet (which is 61W).
However, looking closely at the 1 km visible image at 1045 UTC I see what looks like a weak vortmax (low level, but not surface) near 12.7N and 60.1W about 45 miles southwest of Barbados and 70 miles southeast of St. Lucia. There are two weak low level lines which tend to "curl" around the west side of a possible low level vorticity maximum. This is located west southwest of the main convection approaching Barbados and north of the convection over Trinidad and Tobago.

The system does not seem to be organizing right now, and probably will not for at least the next 12 hours or so. With a forward speed in excess of 25 mph it will be quite difficult to measure/observe westerly surface winds south of a low level vortmax. There is definitely a surface low pressure area in the SLP field as evidenced by the 4 mb pressure fall in Barbados during the 24 hours preceeding 0900 UTC. But I do not believe we will see Ernesto or even a depression until it can slow down over the Caribbean Sea later tonight or Friday. The BAM models slow the speed down considerably after 24 hours and that is when I believe tropical cyclone formation will be more likely. The GFDL's depiction of a northwest turn seems unlikely given the rapid forward speed at the moment.

Good post, I agree...Over the last 6 hours the system also looks to be elongating north to south more...Which is more like a wave. Even so I do see a very strong north wind flow at cloud level over the west side...In a southly flow back up the east side. That is a classic strong Atlantic wave...Which normally do have some turning of the cloud field above 850 millibars. Yeah these fast moving waves have a hard time developing they need to slow down first. I agree once into the caribbean it will likely slow down some. By 65 west I expect it to start slowing down...

Then we need to watch how fast the tutt moves out. I hinted at it yesterday that the tutt may not move out that fast...But the models are trying to build a very strong Anticyclone over the system. Once doing so the cyclone should be slowed down. I expect this to be ernesto by Saturday morning or Afternoon. But not today last night I thought I seen some west wind on sat. But today its gone...

We will see this could still be a beast.

[Lowpressure]

Wasn't it the GFDL that predicted Chris would fizzel then fade over DR. At that point Chris was on the verge of Cane and looked to be a SFL threat then into the GOM as a potential major. Most of us threw out the GFDL scanario, then it pretty much played out.

The GFDL was HORRIBLE for Chris. IT dissipated it before it even got there...and the track was by far one of the worst performers. The CONU was way better...even the GFS was better.

For Chris, the GFDL was a dog.

Thanks AFM, I was not certain which model predicted Chris to fad out over the Greater Antilles. My point was that some models see things and none should be discounted totally at this point. Everyone should watch this scenario.