Cat 4 Hurricane Helene | 140mph 938mb | Landfall Big Bend/Perry

[StretchCT]

14 hours ago, StretchCT said:

AI/RI 

Now that we've sorted out the center here's the AI-RI as of this morning.

A look at the morning sat and it seems to be really close to onshore or just offshore.

Cancun radar is junk. Can't loop right. 

ADT says its offshore.

Raw T has it at hurricane strength. Adj T almost there. 

Edited September 25 by StretchCT

[bigben89]

Can someone explain the "west curvature" once inland US?

 

[StretchCT]

Some webcams

https://www.villapalmarcancun.com/live-webcam

 

 

https://cancun.garzablancaresort.com/live-webcam

[StretchCT]

4 minutes ago, bigben89 said:

Can someone explain the "west curvature" once inland US?

 

Upper low capturing it, ridge to the east and over top.

[FortySixAnd32]

https://www.camscape.com/webcam/cancun-beach-cam/

 

 

[1816]

School is in full swing right now. 

Florida State University in Tallahassee could be in the cross hairs. It's not a place that typically takes a direct hit from a storm like this. 

Most college towns have a lot of structures that are primarily income generating properties catering to student housing. I'm assuming a lot of low quality materials in those. 

If I was a parent of an fsu student I'd be considering bringing them home for this one. 

[StretchCT]

 

[StretchCT]

3 minutes ago, 1816 said:

School is in full swing right now. 

Florida State University in Tallahassee could be in the cross hairs. It's not a place that typically takes a direct hit from a storm like this. 

Most college towns have a lot of structures that are primarily income generating properties catering to student housing. I'm assuming a lot of low quality materials in those. 

If I was a parent of an fsu student I'd be considering bringing them home for this one. 

Just for the extended power outage alone

[FortySixAnd32]

Has anyone considered possible landfall timing coinciding with high tide?

[StretchCT]

Center is bouncing around still on the recon fixes.  Center fix times are: 1 is at 10:59z.  2 is at 11:38z. 3 is at 12:07z 

[Undertakerson2.0]

12 minutes ago, StretchCT said:

Center is bouncing around still on the recon fixes.  Center fix times are: 1 is at 10:59z.  2 is at 11:38z. 3 is at 12:07z 

Seeing some peak winds at 74mph RN - surely will be classified a Cane at 11. 

Edited September 25 by Undertakerson2.0

[NWOhioChaser]

26 minutes ago, StretchCT said:

 

There’s an all inclusive resort there, Iberostar Grand Paraiso that my wife and I have been to a couple of times there. I’d imagine the beaches are empty that way too today. 

[BossaNova]

25 minutes ago, StretchCT said:

Just for the extended power outage alone

Great point.  A place like FSU would have some safe buildings to harbor students for 12-24 hours but as we all know, it can be days or weeks even getting power restored.

[StretchCT]

7 minutes ago, NWOhioChaser said:

There’s an all inclusive resort there, Iberostar Grand Paraiso that my wife and I have been to a couple of times there. I’d imagine the beaches are empty that way too today. 

We've been there too!

[1816]

Crazy how Helene is threading the needle between Cuba and Yucatan. If it had gone solidly over either of those this would be a whole different situation. It's always the little details that make the enormous difference. 

[StretchCT]

54 minutes ago, StretchCT said:

Center is bouncing around still on the recon fixes. 

Center is much farther north now and up a mb. 

[StretchCT]

Adj T is now over hurricane strength and the Final T  and CI are just a few knots under. Like UTS, I would expect an upgrade at 11, if not no later than 2. 

[FortySixAnd32]

State of Florida waiting on the 11am Update....

[StretchCT]

Cuba radar

[StretchCT]

Mission 11 with 3000 ft flight level winds of 93mph now. 

 

[StretchCT]

Discussion notes: elliptical eyewall open on east side, high chance of RI in next 24 hrs, upward revisions in intensity may be required in future advisories, deeper penetration due to size and speed of storm upon landfall.

Will note they upped it to 125mph now.  The HAFS B model UTS posted earlier had 180mph. I would say that's the upward limit, not likely, but within possibilities. NHC does seem to be setting the stage to forecast a stronger storm though. 

Spoiler

Hurricane Helene Discussion Number   9
NWS National Hurricane Center Miami FL       AL092024
1000 AM CDT Wed Sep 25 2024

Air Force Reserve and NOAA Hurricane Hunter aircraft have been
investigating Helene, with each plane recently measuring peak 
flight-level winds of 81 kt and 78 kt, respectively.  Helene has 
therefore become a hurricane with an estimated intensity of 70 kt.  
Dropsonde data also indicate that the pressure has fallen to about 
979 mb.  Radar data from Mexico and Cuba, as well as reconnaissance 
reports, indicate that Helene has formed a partial, elliptical 
eyewall that is open on the east side.

Helene has turned north-northwestward (330/9 kt) and is expected to
turn northward and north-northeastward later today and tonight,
bringing the center to the coast of the Florida Big Bend Thursday
evening. After landfall, Helene is expected to interact with a
deep-layer trough over the Lower Mississippi Valley and swing back
to the northwest and stall near the Tennessee Valley late Friday
into the weekend.  The track guidance remains tightly clustered,
and the NHC forecast is generally just an update of the previous
prediction. It is still too soon at this point to be overly focused
on an exact landfall location and time, since NHC track forecasts
can be off by an average of 60 nm at the 36-hour forecast time.

Helene is expected to move through/over an environment of
relatively low shear, strong upper-level divergence, and sea
surface temperatures of 29-31 degrees Celsius, all of which should
foster additional strengthening.  Rapid Intensification (RI)
indices indicate a high chance of RI during the next 24 hours, and
as a result the NHC intensity forecast shows Helene becoming a
major hurricane by Thursday morning.  There is still some
uncertainty on exactly how strong Helene will get, and upward
adjustments to the forecast intensity could be required in
subsequent advisories if Helene rapidly intensifies more than
forecast.  Regardless, Helene is forecast to be a large major
hurricane when it reaches the Big Bend coast of Florida.   As a
result, storm surge, wind, and rainfall impacts will likely extend
well away from the center and outside the forecast cone,
particularly on the east side.  In addition, the fast forward speed
while Helene crosses the coast will likely result in farther inland
penetration of strong winds over parts of the southeastern United
States after landfall, including strong gusts over higher terrain
of the southern Appalachians.


KEY MESSAGES:

1. Hurricane and tropical storm conditions are expected over
northeastern portions of the Yucatan Peninsula of Mexico today where
Tropical Storm and Hurricane Warnings are in effect.  Tropical storm
conditions are occurring over portions of western Cuba within the
Tropical Storm Warning area, and hurricane conditions are possible
today within the Hurricane Watch area.

2. Due to the large size of Helene, there is a danger of
life-threatening storm surge along the entire west coast of the
Florida Peninsula and Florida Big Bend.  The highest inundation of
greater than 10 ft is expected along the Florida Big Bend coast.
Residents in those areas should follow advice given by local
officials and evacuate if told to do so.

3. Devastating hurricane-force winds are expected across portions 
of northern Florida and southern Georgia where the core of Helene 
moves inland.  Preparations to protect life and property should be 
completed by early Thursday since tropical storm conditions are 
expected to begin within these areas on Thursday.  Because of 
Helene’s expected fast forward speed, damaging and life-threatening 
wind gusts, are expected to penetrate well inland over portions of 
the southeastern United States, including in the higher terrain of 
the southern Appalachians.  

4. Helene will bring heavy rain to portions of the western
Caribbean with potentially significant flooding across western Cuba
and the northeastern Yucatan Peninsula into early Thursday.
Considerable and potentially life-threatening flash and urban
flooding is expected across portions of northwestern and northern
Florida, the Southeast, southern Appalachians, and the Upper
Tennessee Valley Wednesday through Friday. This includes the risk of
landslides across the southern Appalachians. Widespread minor to
moderate river flooding is likely, and isolated major river flooding
is possible.


FORECAST POSITIONS AND MAX WINDS

INIT  25/1500Z 21.6N  86.3W   70 KT  80 MPH
 12H  26/0000Z 23.0N  86.4W   85 KT 100 MPH
 24H  26/1200Z 25.7N  85.7W  105 KT 120 MPH
 36H  27/0000Z 29.7N  84.6W  110 KT 125 MPH
 48H  27/1200Z 34.3N  85.0W   50 KT  60 MPH...INLAND
 60H  28/0000Z 36.6N  86.9W   30 KT  35 MPH...POST-TROP/INLAND
 72H  28/1200Z 36.9N  87.8W   20 KT  25 MPH...POST-TROP/INLAND
 96H  29/1200Z 36.6N  87.9W   15 KT  15 MPH...POST-TROP/INLAND
120H  30/1200Z...DISSIPATED

$$
Forecaster Berg

 

FORECAST POSITIONS AND MAX WINDS

INIT  25/1500Z 21.6N  86.3W   70 KT  80 MPH
 12H  26/0000Z 23.0N  86.4W   85 KT 100 MPH
 24H  26/1200Z 25.7N  85.7W  105 KT 120 MPH
 36H  27/0000Z 29.7N  84.6W  110 KT 125 MPH
 48H  27/1200Z 34.3N  85.0W   50 KT  60 MPH...INLAND
 60H  28/0000Z 36.6N  86.9W   30 KT  35 MPH...POST-TROP/INLAND
 72H  28/1200Z 36.9N  87.8W   20 KT  25 MPH...POST-TROP/INLAND
 96H  29/1200Z 36.6N  87.9W   15 KT  15 MPH...POST-TROP/INLAND
120H  30/1200Z...DISSIPATED

[Undertakerson2.0]

M at Landfall - not a shocker to me, the talk of potential weakening at landfall always a bit suspect to me given this set up. 

[Psu1313]

18 minutes ago, Undertakerson2.0 said:

M at Landfall - not a shocker to me, the talk of potential weakening at landfall always a bit suspect to me given this set up. 

 

The one item that had me potentially thinking we could is the interaction with the cold front. That does not seem to be as much of a player. 

[clm]

14 minutes ago, Psu1313 said:

The one item that had me potentially thinking we could is the interaction with the cold front. That does not seem to be as much of a player. 

https://www.wpc.ncep.noaa.gov/basicwx/day0-7loop.html

By the time that cold front makes any difference, Helene will already have made landfall.  So won't help prior to that, except maybe push some of that rain further east in LA

 

 

 

 

 

[StretchCT]

Wonder if that "dry" air coming in disrupts or delays things.