ATL: IRMA - Post-Tropical - Discussion

[drezee]

this is the precursor to the turn ladies and gentlemen. Hurricane Floyd did the same thing in the Bahamas. People were on here saying the same thing. Here comes the turn...

[wxman57]

Stalling out tells me the steering currents are collapsing; the northwest turn should commence shortly, IMO.

That is true - stalling is generally a precursor to a turn. Trof is digging into the central Gulf now. Irma can't go much farther west.

[PTPatrick]

CDO and esp southern eye wall are starting some cooling. Darker cloud tops starting to wrap the center again. Not sure what radar really shows for eyeballs but looking at sat it could wrap and hold an clear eye but I could also see eye filling too

[KWT]

NHC also showing a slightly slower track than the GFS is suggesting at the moment, so still has 24hrs before landfall. Shear zone will be preventing much more strengthening towards the back end of that forecast but may not mean much. Could see a 1935 labour day situation with big strengthening and deepening and if it stays offshore starts to weaken again further north. Not saying it'll pull a '35 but jsut the general trend of strengthening followed by weakening that helped cause the strengthening in the first place.

[StarmanHDB]

Lantana? Unless there is a tornado in the area it seems too early for that..

Yes, we like sitting in the bathroom for no reason.

We got an extreme alert of tornado activity and told to go to safe room. So we did.

Bunch of tornado warnings in se Florida, heading to the bathroom was a good idea

Sent from my DL8006 using Tapatalk

Sun Sentinel claims two Broward tornadoes....
One supposed touchdown near Federal Hwy and Commercial Blvd in Oakand Park a little over an hour ago and another recently spotted in western Plantation near I75 and US 27 heading toward Weston/Markham Park area.

[johngaltfla]

Stalling out tells me the steering currents are collapsing; the northwest turn should commence shortly, IMO.

That is true - stalling is generally a precursor to a turn. Trof is digging into the central Gulf now. Irma can't go much farther west.

That's a win and lose for us. Win as that prevents a massive storm surge event on the coast but lose at it means the Interstate 75 path appears to be the chosen route for Irma.

[Evil Jeremy]

This is looking like the start of 'the turn'. The precise angle of the turn and the speed after will have huge implications for all of the peninsula.

[tolakram]

 https://twitter.com/splillo/status/906659168102354947




Sam Lillo @splillo
Pressure vs wind for Irma. Recon finding SLP nearing 930mb, w/ winds <110kt. Very rare. Compare to 160kt before near same pressure!!
7:22 PM - Sep 9, 2017

[cheezyWXguy]

Velocities on radar in the NE outer eyewall are beginning to increase and are much stronger than those on the inner. Looks to be getting up to 130mph in some areas. Granted, with the radar site being so far away from the storm, it is looking several thousand feet up above the surface, but even still, these numbers were closer to 115mph no more than a couple hours ago. The inner eyewall looks to be gradually dissipating, and absorbing into the outer eyewall as it does so.

[KWT]

tolakram, that graph is certainly suggestive that if it can develop a good eyewall that doesn't try to replace itself too quickly the wind speeds will go back into the cat-4 range if you take a somewhat typical pressure-wind speed relationship.

[GCANE]

Mesoscale Discussion 1633
NWS Storm Prediction Center Norman OK
0625 PM CDT Sat Sep 09 2017

Areas affected...the East-central Peninsula of Florida

Concerning...Severe potential...Watch possible

Valid 092325Z - 100030Z

Probability of Watch Issuance...40 percent

SUMMARY...Cells offshore about 15-30 miles northeast/east of Vero
Beach may pose a tornado threat as they move into the discussion
area. A WW issuance is being considered.

DISCUSSION...Cells east of the discussion area (on the northeastern
periphery of the circulation associated with Hurricane Irma) are
exhibiting occasional rotation and may pose a threat for brief
tornadoes as they reach coastal areas within the next few hours.
These cells are in an environment containing deep easterly flow and
moderate (2000-2500 J/kg MUCAPE) buoyancy - highest along coastal
areas and offshore. Although latest 88D profiler data exhibits
relatively marginal shear for updraft rotation (around 100 m2/s2
0-3km SRH), this shear will likely increase in this region with time
as Irma moves northwestward toward the southern Florida Peninsula.
It is currently unclear how far inland the tornado threat will exist
as buoyancy weakens with inland extent. However, the approach of
these cells toward coastal areas suggests an increasing tornado
threat over the next hour or so, and a WW is being considered for
the region.

..Cook/Grams.. 09/09/2017

[Digital-TC-Chaser]

Getting that Gnarly appearance back.

[bamajammer4eva]

Which eye is used for direction of movement? looks like the inner one is wobbling erratically inside the outer one which is stationary.

[jlauderdal]

Yes, we like sitting in the bathroom for no reason.

We got an extreme alert of tornado activity and told to go to safe room. So we did.

Bunch of tornado warnings in se Florida, heading to the bathroom was a good idea

Sent from my DL8006 using Tapatalk

Sun Sentinel claims two Broward tornadoes....
One supposed touchdown near Federal Hwy and Commercial Blvd in Oakand Park a little over an hour ago and another recently spotted in western Plantation near I75 and US 27 heading toward Weston/Markham Park area.

If there was damage at federal and commercial I will walk over in the morning and report back, I'm 5 mins away

Sent from my DL8006 using Tapatalk

[Zarniwoop]

Hopefully the eyes fight for 24 hours again.

[lrak]

Which eye is used for direction of movement? looks like the inner one is wobbling erratically inside the outer one which is stationary.

I'm sorry I don't have an answer but try and keep an eye on this one https://radar.weather.gov/radar.php?product=N0Z&rid=BYX&loop=yes

[skillz]

First post here, yay! I'm residing in vero Beach, FL
Expected to have Tornado Warnings within the next 30-45 mins from cells coming in Westward, offshore.

Will Irma go due North and ride the spine of Florida? That would be worst case scenario for East Coast Central Florida...

[LarryWx]

This is looking like the start of 'the turn'. The precise angle of the turn and the speed after will have huge implications for all of the peninsula.

I also think she is on the verge of a turn. I just took another look at some 6 hour interval 12Z Euro maps I have. They showed the current actual position to be right where the 12Z Euro 12 hour map had her. Furthermore, that Euro showed her 6 hour averaged movement from 2PM til 8PM to average just a little N of due W. The next map, the hour 18 map for 2AM EDT, shows quite a dramatic movement to the NNW. So, in deference to the Euro and when considering the recent stall, I think we're just about to see the turn to the NNW commence. Other opinions? This is like the most important part of the track right here!

[craptacular]

AF302 just took off from Keesler. It will take a bit to get there for the next center fix ... looks like Irma is patiently waiting.

[Michele B]

Stalling out tells me the steering currents are collapsing; the northwest turn should commence shortly, IMO.

I think that's the consensus.