Major Hurricane Helene

[DDweatherman]

Just now, beanskip said:

Nope, this isn't right either for GFS -- it's slightly southEAST. Landfall at exact same time, just to the right. 

Yeah about 15 miles southeast from 0z, basically Steinhatchee. If this does LF there, the surge in cedar key could be devastating for sure. Even folks up the US19 coast from Tampa get a lot of water on that track and approach. 

[TPAwx]

The debate on model validity is interesting but less relevant as we are quickly shifting to now casting and obs phases.  
 

I appreciate the expertise and input shared here to help understand what’s happening and what to expect with Helene.

[CoastalWx]

Not that I encourage using the HRRR for this right now, but check out the srfc wind gusts for this. I think the idea of what it shows makes sense. A very large windfield to the east that rips into SC. Also, the backside of this with the pressure rises in the ATL area likely bring the strongest winds there on the backside. 

But man the rains in the high country of NC and SC.

[wncsnow]

A lot of Mets are talking about the eastward shift they have noticed and they expect NHC to move more east at 11 am. 

[OSUmetstud]

Just now, beanskip said:

Nope, this isn't right either for GFS -- it's slightly southEAST. Landfall at exact same time, just to the right. 

Looking at the T+6 h forecast from both the GFS and ECMWF models. It corrected northwest from the previous 00z run. Also, the 06z ECMWF landfall location is definitely west of the 00z ecmwf landfall location. 

 

 

[beanskip]

5 minutes ago, beanskip said:

Not mad at all. Seems like if we are going to say a model run trended a certain direction or speed it ought to be right.

 

No actually, that's not right - I am a little peeved. This board used to be a place where a met wouldn't mock you for asking questions and trying learn. I want to understand the apparent disconnect between the spaghetti plots and operational runs - not just that there IS a difference but WHY? I want to learn and understand why the operational Euro -- the KING -- is outside the NHC cone 18 hours from landfall.

I've been on this board for more than a decade. I think i've earned some respect and some continuing education.

Instead -- "get out of here."

So yeah, if my stuff is going to be ridiculed, you better get the trends right or I'm going to call it out.

[DDweatherman]

1 minute ago, OSUmetstud said:

Looking at the T+6 h forecast from both the GFS and ECMWF models. It corrected northwest from the previous 00z run. Also, the 06z ECMWF landfall location is definitely west of the 00z ecmwf landfall location. 

 

 

Looking at Key West radar since we have the eastern eye wall in range, it’s more or less moving due N at the moment. 

[wncsnow]

FWIW both NAMS landfall around Perry

[DDweatherman]

3 minutes ago, wncsnow said:

FWIW both NAMS landfall around Perry

Pretty concerning for Valdosta if they are on the eastern eyewall. It’s going to be hauling through there with bigtime winds. If this gets to major today might be a landmark event there. 

[CoastalWx]

3 minutes ago, beanskip said:

No actually, that's not right - I am a little peeved. This board used to be a place where a met wouldn't mock you for asking questions and trying learn. I want to understand the apparent disconnect between the spaghetti plots and operational runs - not just that there IS a difference but WHY? I want to learn and understand why the operational Euro -- the KING -- is outside the NHC cone 18 hours from landfall.

I've been on this board for more than a decade. I think i've earned some respect and some continuing education.

Instead -- "get out of here."

So yeah, if my stuff is going to be ridiculed, you better get the trends right or I'm going to call it out.

It is far from the king and virtually unusable lately. 

The spaghetti plots and globals like GFS and Euro also have different physics etc. Perhaps the more complicated interactions with the short wave troughs favored the globals a bit this go around. 

But, over the years I've also learned not to discount the tropical models. I know in New England, when they sniff that east trend with the westerlies, forget it. It's over. 

That's why hopefully humans can add value and try to adjust the forecast accordingly. There is also high stakes here and you need to weigh all of this when doing a forecast. It's easy for weenies to make a call sitting back at their desk..but it's a whole other level when your forecast is driving evacuations with billions of dollars in assets on the line as well as human lives. 

 

[WishingForWarmWeather]

52 minutes ago, cptcatz said:

I'm gonna get weenied here but satellite looks like it's making a significant northeast motion and making a bee line into the penninsula. I'm calling landfall around Cedar Key. If it doesn't turn more north, the surge in Tampa could be even worse than thought. 

Nah. You’re not a weenie. 
 

Helene actual vs NHC track

[BoulderWX]

2 minutes ago, wncsnow said:

FWIW both NAMS landfall around Perry

In terms of location, that would be best case scenario placing TLH and ATL on the western side. If it were to be closer to Panama City or Port St Joe, the impacts would be significantly worse. Will be interesting to see the details ironed out over the next 6-12 hours but hopeful this stays far enough east to mitigate some of the impacts for the most populated areas in the cone. 

[dan11295]

Latest extrap pressures still in 962 mb range been steady state pressure wise past few hours.

[OSUmetstud]

The NHC cone only represents 5-year average track error at each forecast point in time. TCs will verify outside of the cone from forecast about 1/3rd of the time. 

[bdgwx]

11 minutes ago, beanskip said:

is outside the NHC cone 18 hours from landfall.

it is important to understand that the NHC cone is the 1σ uncertainty envelope based on track errors over the last 5 years. So we expect the actual track to fall outside the cone about 32% of time. It would also be the expectation that of all the models available to consider some would show tracks outside of the cone as well.

[jbenedet]

Currently has a Cat 3 look on IR. 

[MN Transplant]

7 minutes ago, WishingForWarmWeather said:

Nah. You’re not a weenie. 
 

Helene actual vs NHC track

That's a wobble.  This thing is headed to Apalachee Bay.

Idalia smacked around Valdosta pretty well last year and this looks like it could be worse.

[OSUmetstud]

raw advanced dvorak is in the high 5s but i would really like to see the southern eyewall get going to see more intensification in earnest. 

[DDweatherman]

4 minutes ago, jbenedet said:

Currently has a Cat 3 look on IR. 

I think we’re going to see her ramp up fairly nicely the next 4-6 hours. 

[erbsonci]

20 minutes ago, DDweatherman said:

Yeah about 15 miles southeast from 0z, basically Steinhatchee. If this does LF there, the surge in cedar key could be devastating for sure. Even folks up the US19 coast from Tampa get a lot of water on that track and approach. 

 

At least in North County Pinellas, US 19 is the highest ground, although there are areas around it which are more low closer to the water. Treasure Island and Venice (beach areas further south in Pinellas and past Sarasota, respectively) are completely flooded out. 

[DDweatherman]

Just now, erbsonci said:

 

At least in North County Pinellas, US 19 is the highest ground, although there are areas around it which are more low closer to the water. Treasure Island and Venice (beach areas further south in Pinellas and past Sarasota, respectively) are completely flooded out. 

Yep, those spots down near Laurel and Osprey are low lying near Venice Beach. Some sit below sea level. I was just there this week, got out of town this morning. 

[WishingForWarmWeather]

4 minutes ago, MN Transplant said:

That's a wobble.  This thing is headed to Apalachee Bay.

Idalia smacked around Valdosta pretty well last year and this looks like it could be worse.

Yeah - definitely is going to wobble especially as the VHTs circling circling and dragging that center all over. I just meant they weren’t seeing things - it’s on the east side of things right now. It’ll likely course correct back towards the west and on track! 
 

those poor folks can’t catch a break in that area. So many in the past few years. And in model fantasy land there’s another behind Helene land falling in a very similar location. 

[SnowGoose69]

The 3KM NAM continues to show that tendency of not wanting to capture and hook til its 965-970 or weaker.

[erbsonci]

2 minutes ago, DDweatherman said:

Yep, those spots down near Laurel and Osprey are low lying near Venice Beach. Some sit below sea level. I was just there this week, got out of town this morning. 

Yes, I don't think most people realize how north of Pinellas all the way to Tally is basically very low areas at sea level. Not every single track of land but 99.9% on the water-side of US 19. There's a reason it's never built up. You'd be amazed at how far and high the water comes in. Stay safe if you're still in FL, @DDweatherman.

[DDweatherman]

2 minutes ago, erbsonci said:

Yes, I don't think most people realize how north of Pinellas all the way to Tally is basically very low areas at sea level. Not every single track of land but 99.9% on the water-side of US 19. There's a reason it's never built up. You'd be amazed at how far and high the water comes in. Stay safe if you're still in FL, @DDweatherman.

I’ve driven that coast line and also driven the US 19/27/98 all the way to Destin, it’s low lying, quite poor areas that are very spread out population wise. I drove through there over a year after Michael and most of the damage off the immediate roads was almost untouched. 

[Master of Disaster]

Is that eye 32 miles across? Did I read that correctly? 

 

 

[OSUmetstud]

Just now, Master of Disaster said:

Is that eye 32 miles across? Did I read that correctly? 

 

 

It's elliptical and open sw now, but pretty large eye overall. 

F. OPEN SW
G. E13/38/22

 

[jm1220]

34 minutes ago, wncsnow said:

A lot of Mets are talking about the eastward shift they have noticed and they expect NHC to move more east at 11 am. 

It’s almost a given with these eastern Gulf storms that they shift east in the end. Hopefully it doesn’t keep going too far. 

[Wcdubski]

37 minutes ago, CoastalWx said:

Not that I encourage using the HRRR for this right now, but check out the srfc wind gusts for this. I think the idea of what it shows makes sense. A very large windfield to the east that rips into SC. Also, the backside of this with the pressure rises in the ATL area likely bring the strongest winds there on the backside. 

But man the rains in the high country of NC and SC.

Long time lurker and knowledge gatherer, thanks to everyone here for the many years of true service. I am 30 minutes East of Atlanta, My brother's family is in Valdese, NC & my nephew is currently at App State in Watauga County NC, so I really appreciate the high country knowledge sprinkled in here. Helps me help them, they don't do weather aware very well. Stay safe everyone and again, thank you all.

[NJwx85]

Prolific rainfall amounts incoming for Upstate South Carolina and Western North Carolina into the Smokies due to upsloping.