Tropical Storm Isaac, Part 2: Isaac Moving Into The Gulf Of Mexico-Hurricane Warnings For Morgan City, LA/MS/AL & FL Panhandle To Destin, FL

[turtlehurricane]

New eye/eyewall feature taking shape near 24.6 °N, 82.7 °W. Recon about to investigate...

[earthlight]

Just glancing at the early 00z track guidance, it's pretty clear that the members which are still bringing Isaac east of the MS Delta have the center of the storm jogging more NNW over the next 12 to 24 hours. It will be interesting to watch the heading over the 12 hours or so as the guidance suggests we could have an idea whether the eastern solutions have any merit by then.

[andyhb]

It's not that unusual for intensifying tropical systems. I mean if you think about it..intensification usually goes along with stronger updrafts and colder cloud tops...you are naturally gonna electrify the atmosphere a bit more. It also doesn't mean RI either. It's a blob of convection that is really going to town.

Sort of like how increased lightning tends to indicate an intensifying supercell (or any kind of thunderstorm for that matter).

[CoastalWx]

Sort of like how increased lightning tends to indicate an intensifying supercell (or any kind of thunderstorm for that matter).

Well sure, but remember that in most TCs..updraft strength is much less than what we see in Plains supercells. Much weaker usually.

[turtlehurricane]

I put a placemarker where the new center is taking shape, this is kinda a big deal.

[Eskimo Joe]

Just an FYI, there is some pretty good Public Safety/Power Outage links / Press Release information available on the following Social Media feeds, particularly Facebook:

*James Spann

*Ready Georgia

*New Orleans Office of Homeland Security & Emergency Preparedness

*Mississippi Emergency Management Agency

*Louisiana Governor's Office of Homeland Security and Emergency Preparedness

[Uncle Bobby]

New eye/eyewall feature taking shape near 24.6 °N, 82.7 °W. Recon about to investigate...

I have to disagree. I think Isaac looks absolutely awful on radar right now. I believe that we are hours away from any eye formation, at the least.

[Bostonseminole]

I put a placemarker where the new center is taking shape, this is kinda a big deal.

. That seems pretty far north based on latest recon findings, is that based on radar interpretation?

Using IPad or IPhone or BB so my grammar may suck.

[samdman95]

I put a placemarker where the new center is taking shape, this is kinda a big deal.

Will this significantly alter the overall path of Isaac, or is it just more of a short term blip?

[turtlehurricane]

I have to disagree. I think Isaac looks absolutely awful on radar right now. I believe that we are hours away from any eye formation, at the least.

The only reason it looked awful was because it relocated to under the deepest part of the convection, but it's looking better by the minute now and I believe the feature at 24.6 °N, 82.7 °W is a formative eyewall. It might collapse for all we know but that is the current situation. Doppler velocities confirm that it's the center above 2 miles and that's been descending.

[turtlehurricane]

. That seems pretty far north based on latest recon findings, is that based on radar interpretation?

Using IPad or IPhone or BB so my grammar may suck.

This velocity image in the mid-levels should help, the center of the spiral is what I'm talking about.

[FredRed]

New eye/eyewall feature taking shape near 24.6 °N, 82.7 °W. Recon about to investigate...

That's the mid-level/upper-level center. We'll see if its able to bring in the lower level circulation. Starting to see more green on the 0.5 indicating that the lower mid-level is working its way down.... still has a few hours to go.

Green echoes to the NW of the meso indicator.

[Ground Scouring]

There’s actually a tornado-warned couplet that is heading for the NHC now. SPC might need to do a mesoscale discussion on South FL, as the center reformation plus organization has enhanced the low-level hodographs in SE FL.

[David Reimer]

No disrespect intended, but some guys on here have crappy velocity color tables. Head on over to www.grlevelxstuff.com to get some better ones!

Anyway, BYX is starting to pick up a few 55 knot base velocity signatures around 4,000 feet.

[tornadotony]

I think even the lowest tilt of KBYX radar is starting to show hints of that circulation descending due W of the Dry Tortugas.

[jcwxguy]

I think even the lowest tilt of KBYX radar is starting to show hints of that circulation descending due W of the Dry Tortugas.

sorry, crappy quality, but a very short loop

(click for loop)

[WhiteoutWX]

Increased lightning indicates there's more snow and ice aloft if I know my microphysics right, which is a result of deeper convection and cooler cloud tops. The sun going down probably helps too for cooler cloud tops.

The increased lightning can be used as a rough indicator of updraft velocities and mass flux within the convection. More lighting= more rigorous convection.

[Pilotwx]

Water vapor confirms this thing is getting it's act together.

http://www.goes.noaa.gov/GSSLOOPS/ecwv.html

[LakeEffectKing]

[wi_fl_wx]

I think there was a tornado near downtown Coral Gables at around 9:45 PM. I witnessed about 5 transformer explosions in rapid succession. It lasted about 30 seconds. I was too far away to confirm but considering the hook echo and tornado warning I suspect it was on the ground for around 30 seconds. The winds have also continued to increase here and are as high as they have been all day. Maybe 20-30 mph sustained or so with gusts around 40. There are a few tree branches down but power is still on.

[wxsmwhrms]

Definitely seems to be an increase in extent and top magnitude of base velocity values of KBYQ, and circulation definitely becoming more apparent at 0.5 degrees.

[David Reimer]

Looks like Isaac may be dealing with a little bit of dry air entrainment with the southern part of the convective blob. Otherwise, the inner core is looking quite healthy at this point.

[tornadotony]

Definitely seems to be an increase in extent and top magnitude of base velocity values of KBYQ, and circulation definitely becoming more apparent at 0.5 degrees.

More importantly, intense convection is wrapped almost all the way around that circulation.

[BeauDodson]

Just an FYI, there is some pretty good Public Safety/Power Outage links / Press Release information available on the following Social Media feeds, particularly Facebook:

*James Spann

*Ready Georgia

*New Orleans Office of Homeland Security & Emergency Preparedness

*Mississippi Emergency Management Agency

*Louisiana Governor's Office of Homeland Security and Emergency Preparedness

*James Spann or for new people James Spann II

*Ready Georgia

*New Orleans Office of Homeland Security & Emergency Preparedness

*Mississippi Emergency Management Agency

*Louisiana Governor's Office of Homeland Security and Emergency Preparedness

[turtlehurricane]

Going NW pretty quick, 24.7 °N, 83.0 °W. Looking alot more complex than the standard partial eyewall with all this downshear reformation, and with the surface low dragging behind. Call it whatever you want, it's some sort of deep convective structure which is driving a strong tropical storm. The mid-level low coupled with the reflectivity structure is definitely driving the sfc low though, it's like a vacuum and shows where the convection is evacuating the most mass.

[ALhurricane]

Still can't buy the far west solution just yet, especially with UKMET/ECMWF still east. The general weakness is still there which should induce a more poleward motion...albeit a slowing motion. Very tough to call though. I certainly wouldn't change the NHC track at 10pm. Let's see what the 00z guidance shows.

[FredRed]

Now we're getting some surface involvement with the mid-level circulation... may even be developing a warm spot eye.

[WeatherMimmi]

Going NW pretty quick, 24.7 °N, 83.0 °W. Looking alot more complex than the standard partial eyewall with all this downshear reformation, and with the surface low dragging behind. Call it whatever you want, it's some sort of deep convective structure which is driving a strong tropical storm. The mid-level low coupled with the reflectivity structure is definitely driving the sfc low though, it's like a vacuum and shows where the convection is evacuating the most mass.

I know that the TWc sees what we see but has not made any comment on this, do you see the Euro track taking hold?

[wxsmwhrms]

More importantly, intense convection is wrapped almost all the way around that circulation.

Certainly looks like the center is more centered in the convective mass on satellite.

[wxsmwhrms]

Still can't buy the far west solution just yet, especially with UKMET/ECMWF still east. The general weakness is still there which should induce a more poleward motion...albeit a slowing motion. Very tough to call though. I certainly wouldn't change the NHC track at 10pm. Let's see what the 00z guidance shows.

Well, they did shift it a bit farther W. Now coming in pretty much right at the mouth of the MS River.