ATL: HERMINE - Post-Tropical - Discussion

[cycloneye]

 https://twitter.com/WeatherBug/status/768521323572293632

[gatorcane]

either the LLC is moving NW or that is a vort spinning out NE of Puerto Rico?

Clearly the mid-level and low-level circulations are not aligned. New convection firing along the northern periphery of the broad low.

SAT loop link:
http://rammb.cira.colostate.edu/ramsdis ... display=12

[SoupBone]

850mb vorticity is strong but the upper-anticyclone is sitting just to the south over the Northern Caribbean Sea. So just marginal conditions for development as the NHC pointed out.

This is about the 30th time I've asked this so hopefully someone will respond. This is the third time those shear charts have showed 30 knot shear covering a huge chunk of the GoM. Was that expected, and is it forecast to remain in place?

Shear charts show what is happening currently. They are not reflective of a future conditions.

I understand that it shows current conditions. Are there any indications that those conditions will still exist several days down?

[Aric Dunn]

either the LLC is moving NW or that is a vort spinning out NE of Puerto Rico?

Clearly the mid-level and low-level circulations are not aligned. New convection firing along the northern periphery of the broad low.

SAT loop link:
http://rammb.cira.colostate.edu/ramsdis ... display=12

it is the main llc just moving to fast to proce and significant west winds with out deep convection. should low way down in about 6 to 8 hours.

[RL3AO]

850mb vorticity is strong but the upper-anticyclone is sitting just to the south over the Northern Caribbean Sea. So just marginal conditions for development as the NHC pointed out.

This is about the 30th time I've asked this so hopefully someone will respond. This is the third time those shear charts have showed 30 knot shear covering a huge chunk of the GoM. Was that expected, and is it forecast to remain in place?

Hope this helps.

[AutoPenalti]

This thing is trying it's very best to escape the shear. I'm betting that during DMAX it's back to normal.

[tolakram]

Original LLC is being ejected NW, no denying that the low level flow has changed around Hispaniola with clouds now moving north in the Mona Passage. How interesting, yes? Something that doesn't exist can't be shredded so I think that talk is unwarranted but it seems the setup is more complex than the Euro has shown. It's also quite possible that the "old" LLC will still be the primary once the system gets further away from the Islands? Just guessing.

Speed it up, of course.
http://weather.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20CONUS&lat=19&lon=-61&info=vis&zoom=1&width=1000&height=800&quality=90&type=Animation&palette=ir1.pal&numframes=30&mapcolor=black

[gatorcane]

Aric, that LLC NE of Puerto Rico appears to be gaining latitude pretty quickly, seems already more north than the models have been showing thought it could slow down as you mention and maybe wobble back to the west to correct. Maybe it just dies off and another LLC forms later once convection builds again?

[OuterBanker]

Looking through Facebook and people are not really taking much action.

http://i63.tinypic.com/2w2g5kp.jpg
http://i65.tinypic.com/2cysgmp.jpg

Wow! My assumption is that the folks making those comments are pretty young. I just can't see anyone who's old enough to remember Andrew making such statements.

Born before Andrew. Gimme a break. Just after my 9th birthday Donna hit us (If you do the math you will realize that I start Medicare next week)

Anyway, I can't believe the latest Euro. It's caved into the GFS.

That would also kinda mess up our Labor Day weekend.

JB doesn't believe it and isn't going to change his forecast (for now).

If the GFS is correct it will be the biggest coup it has ever pulled.

Waiting and seeing.

[Weatherboy1]

either the LLC is moving NW or that is a vort spinning out NE of Puerto Rico?

Clearly the mid-level and low-level circulations are not aligned. New convection firing along the northern periphery of the broad low.

SAT loop link:
http://rammb.cira.colostate.edu/ramsdis ... display=12

I still think the dominant LLC is the one to the NE of PR, as you noted. But it's going to need convection firing off over the center for this to get a designation, I'm guessing. Ironically, the dying off of the MLC to the SE probably will help in that regard down the line. We'll see.

[SoupBone]

850mb vorticity is strong but the upper-anticyclone is sitting just to the south over the Northern Caribbean Sea. So just marginal conditions for development as the NHC pointed out.

This is about the 30th time I've asked this so hopefully someone will respond. This is the third time those shear charts have showed 30 knot shear covering a huge chunk of the GoM. Was that expected, and is it forecast to remain in place?

Hope this helps.

Forgive me for posting a one liner, but thanks!

[Blown Away]

Aric, that LLC NE of Puerto Rico appears to be gaining latitude pretty quickly, seems already more north than the models have been showing thought it could slow down as you mention and maybe wobble back to the west to correct. Maybe it just dies off and another LLC forms later once convection builds again?

Maybe, but a NW "Hump" offshore FL and then back to the W under building ridge is not that uncommon... Many examples of this track... I'm going with an eventual close call just E of SFL track or a smoother traditional track into SFL then NW across the peninsula, maybe into the EGOM, than N into GA...

[seatrump]

Hello from the Turks and Caicos islands. I'm a weather enthusiast living in Providenciales. I contributed a little last year during Joacquin. Since then, I have installed a weather station and weather camera.

I apologize if these links are not permitted, mod can remove them.
Weather station : https://www.wunderground.com/personal-w ... =ICAICOSI6
Webcam : https://www.wunderground.com/webcams/Zray/1/show.html

The day started perfectly clear but now we have large masses of TC in all quadrants. Different from our usual spotty afternoon thunderstorms.

I'll supply updates if any significant or severe weather occurs over the next 24-48 hours. The local disaster management authority is warning mostly of flooding at the present time. Rain would be much appreciated! I haven't done too much in way of preparation so far as I don't have to worry about flooding.

[Aric Dunn]

Aric, that LLC NE of Puerto Rico appears to be gaining latitude pretty quickly, seems already more north than the models have been showing thought it could slow down as you mention and maybe wobble back to the west to correct. Maybe it just dies off and another LLC forms later once convection builds again?

yeah It appears after speaking with some people. the northern half of the wave axis that shot west yesterday and is now running into HR also helped accelerate the llc in this motion also caused it to outrun the MLC during the morning. if you notice the area near HR is now moving slight wsw into the island as the llc moves faster to the nw kind of a fujiwhara once the llv crosses the longitude of about the mona passage we should see it slow down and convection build and the inflow return on the SW side.

[SouthFLTropics]

Aric, that LLC NE of Puerto Rico appears to be gaining latitude pretty quickly, seems already more north than the models have been showing thought it could slow down as you mention and maybe wobble back to the west to correct. Maybe it just dies off and another LLC forms later once convection builds again?

yeah It appears after speaking with some people. the northern half of the wave axis that shot west yesterday and is now running into HR also helped accelerate the llc in this motion also caused it to outrun the MLC during the morning. if you notice the area near HR is now moving slight wsw into the island as the llc moves faster to the nw kind of a fujiwhara once the llv crosses the longitude of about the mona passage we should see it slow down and convection build and the inflow return on the SW side.

Aric, I take it that the feature in the Mona Passage right now is not related to the dominant LLC??? It sure appears to have some decent rotation to it as it wraps into the Dominican Republic. If 99L wants to survive it better hope the feature NE of PR is the dominant LLC.

[Steve H.]

Yes, the animation the Tolakram had a few posts ago is an excellent shot of the "main" vort NNE of PR is probably the one that will be the primary in the end. It has the tighter "circulation."

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. For official information, please refer to products from the National Hurricane Center and National Weather Service.

[Aric Dunn]

Aric, that LLC NE of Puerto Rico appears to be gaining latitude pretty quickly, seems already more north than the models have been showing thought it could slow down as you mention and maybe wobble back to the west to correct. Maybe it just dies off and another LLC forms later once convection builds again?

yeah It appears after speaking with some people. the northern half of the wave axis that shot west yesterday and is now running into HR also helped accelerate the llc in this motion also caused it to outrun the MLC during the morning. if you notice the area near HR is now moving slight wsw into the island as the llc moves faster to the nw kind of a fujiwhara once the llv crosses the longitude of about the mona passage we should see it slow down and convection build and the inflow return on the SW side.

Aric, I take it that the feature in the Mona Passage right now is not related to the dominant LLC??? It sure appears to have some decent rotation to it as it wraps into the Dominican Republic. If 99L wants to survive it better hope the feature NE of PR is the dominant LLC.

its the leftover northern half of the wave axis that shot west yesterday. its running into HR and will dissipate. it just took a lot of the rotational energy with it. but HR will take care of that bit

[OuterBanker]

Aric, that LLC NE of Puerto Rico appears to be gaining latitude pretty quickly, seems already more north than the models have been showing thought it could slow down as you mention and maybe wobble back to the west to correct. Maybe it just dies off and another LLC forms later once convection builds again?

yeah It appears after speaking with some people. the northern half of the wave axis that shot west yesterday and is now running into HR also helped accelerate the llc in this motion also caused it to outrun the MLC during the morning. if you notice the area near HR is now moving slight wsw into the island as the llc moves faster to the nw kind of a fujiwhara once the llv crosses the longitude of about the mona passage we should see it slow down and convection build and the inflow return on the SW side.

I agree with that scenario. Looks like the most logical explanation.

Btw, anyone notice the 981 around 19N 50W on the 240 Euro?

[alienstorm]

Let's wait until it is develop and see what happens...

[Blown Away]

either the LLC is moving NW or that is a vort spinning out NE of Puerto Rico?

Clearly the mid-level and low-level circulations are not aligned. New convection firing along the northern periphery of the broad low.

SAT loop link:
http://rammb.cira.colostate.edu/ramsdis ... display=12

it is the main llc just moving to fast to proce and significant west winds with out deep convection. should low way down in about 6 to 8 hours.

18z TAFB sees 99L just off Hispaniola in 24 hours...