Major Hurricane Florence: STORM MODE THREAD

[KoalaBeer]

Definitely curious to see what Euro ensembles show. Does any have the 00z ones available I don't think I ever saw them. 

[ag3]

2 minutes ago, mappy said:

one run outcome is not a trend, nor can one say its a the start of a trend. 

 

Never said it was. Just gives credence to several other models who have shown this type of stall just offshore and then drift south. Euro is not the end all be all model that some here and other places think it is.

[SnowGoose69]

Anytime a stall is expected or modeled the system tends to do so further off the coast than expected.  It’s still too early at this point to know if the stall will occur, but if 24-36 hours our from landfall it’s becoming a consensus forecast you can bet it’ll do so a good 30-40 miles plus off the coast which will likely keep the eyewall off shore.  This is due to the tendency for hurricanes to attempt the path of least resistance.  Even when they’re chugging along at 20kts they often jog right for a bit at the end.  Depending how long the stall lasts will determine what strength it is when and if it finally comes ashore.  If it takes a more south track and stalls off MYR it’s much more risky this is still a 3 when it backs in 

[Quincy]

Just now, ROOSTA said:

Intensity you know is the last feature, parameter to be forecast correctly.  Gulf stream waters around 90F are pretty deep and close to the coast. It's an unknown so leave at that.     

The issue with a slowing/stalling hurricane is going to be upwelling, plus the water depth gets shallower closer to the coast. Major hurricanes have been known to have sometimes wild fluctuations in intensity (ERC, as one example), but it's hard to see this thing strengthening much, if at all, beyond Wednesday.

[mappy]

Just now, ag3 said:

 

Never said it was. Just gives credence to several other models who have shown this type of stall just offshore and then drift south.

I understand that, but just yesterday people were tossing the GFS run that did the exact same thing the Euro did. So which is it? The Euro yesterday, or the GFS today? 

The ridge is the big player here -- and I honestly think up until it gets to the coast, those details, the slowing down/strength/stall/where it goes, will literally be worked out last minute. 

People need to be careful making definitive statements. 

[HIPPYVALLEY]

12 minutes ago, TriPol said:

Has there ever been a storm that's stalled right before making landfall in the Carolinas?

 A better question might be is there an analog of a hurricane that has ever moved south down the coast like that?

[emblaze2]

3 minutes ago, KoalaBeer said:

Definitely curious to see what Euro ensembles show. Does any have the 00z ones available I don't think I ever saw them. 

Stall just inland of Cape Fear, then slow drift southwest.

[SnoSki14]

I can't imagine a large major hurricane just dangling offshore for days. 

In NJ we just had moderate coastal flooding from stronger than normal onshore flow. 

[40/70 Benchmark]

3 minutes ago, ROOSTA said:

Intensity you know is the last feature, parameter to be forecast correctly.  Gulf stream waters around 90F are pretty deep and close to the coast. It's an unknown so leave at that.     

Yea, we don't know. Revisit...I feel strongly that it will be weakening upon approach given a stall scenario due to upwelling/potential shear increase, but certainly other aspects could be every bit as damaging.

We'll see.

 

[ag3]

2 minutes ago, mappy said:

I understand that, but just yesterday people were tossing the GFS run that did the exact same thing the Euro did. So which is it? The Euro yesterday, or the GFS today? 

The ridge is the big player here -- and I honestly think up until it gets to the coast, those details, the slowing down/strength/stall/where it goes, will literally be worked out last minute. 

People need to be careful making definitive statements. 

Agree. And it's not just the GFS that has shown the stall and drift south. Many others models have as well.

 

[ag3]

1 minute ago, 40/70 Benchmark said:

Yea, we don't know. Revisit...I feel strongly that it will be weakening upon approach given a stall scenario due to upwelling/potential shear increase, but certainly other aspects could be every bit as damaging.

We'll see.

 

Agree. I think if it suddenly stalls like that, the western eyewall would detereorate rapidly from land friction, keeping the heaviest winds offshore or immediately on the shoreline. But a stall like this, would create catastrophic flooding like Harvey.

[GreensboroWx]

One has to remember this is a BIG hurricane and whether or not it's a 2 or 3 or whatever, the flooding potential is going to be unreal. Thrown in hurricane force winds and you have a disaster. I certainly hope the stall scenario doesn't play out but it's looking more and more likely Florence is going to slow down significantly either and creep through NC/SC or just offshore. Either way, it's just not a good thing for millions of people in its path or in its radius, which include me. 

[taylorsweather]

2 minutes ago, NJwx85 said:

Shift SW

Wrong map.  That was from yesterday

[gymengineer]

19 minutes ago, TriPol said:

Has there ever been a storm that's stalled right before making landfall in the Carolinas?

Check out Hurricane Diana (1984).

[NJwx85]

3 minutes ago, ag3 said:

Agree. I think if it suddenly stalls like that, the western eyewall would detereorate rapidly from land friction, keeping the heaviest winds offshore or immediately on the shoreline. But a stall like this, would create catastrophic flooding like Harvey.

Typically in these situations you have a digging trough helping to wrap dry air into the circulation from the South, in this case, no trough, a lot less dry air.

[NJwx85]

Just now, Taylorsweather said:

Wrong map.  That was from yesterday

I deleted it a second after I put it up. 

[kvskelton]

6 minutes ago, NJwx85 said:

I deleted it a second after I put it up. 

I believe this is the current image you were trying to post. 

[Windspeed]

New 12z ECMWF totals:

[TPAwx]

[bdgwx]

Probably splitting hairs, but that looks like a 35" contour on Wilmington.

[mappy]

2 minutes ago, bdgwx said:

Probably splitting hairs, but that looks like a 35" contour on Wilmington.

technically Wilmington is within the 35" contour, so it would be 35"+

[beanskip]

So, just to recap the 12z model suite at 120 hours:

 

Euro -- Hilton Head, S.C.

GFS -- Middlesboro, Kentucky

CMC -- Charleston, WV

HWRF -- Bowling Green, Ky

HMON -- Dissipating, but last seen over Montgomery, Ala.

 

Dear Lord, please bless the NHC forecasters  .....

[ag3]

A fair amount of the EPS members now showing a stall and then drift N or S. 

[ag3]

Just now, ag3 said:

A fair amount of the EPS members now showing a stall and then drift N or S. 

Looking more closely, the far majority of them now show a stall just offshore with only a few making it entirely onto land.

[hawkeye_wx]

2 minutes ago, ag3 said:

A fair amount of the EPS members now showing a stall and then drift N or S. 

Yeah, pretty much all of them are stalling and weakening Florence somewhere along or just off the coast of NC or SC.

[HIPPYVALLEY]

18 minutes ago, Windspeed said:

New 12z ECMWF totals:

It wouldn't take much of a shift to swing those 6-8" amounts into Asheville area which would start getting dicey for them.

[PackGrad05]

The EPS solution would be great for Central NC.  Anyone have an expected wind map for Central NC if the EPS verified?  I'm thinking tropical storm force gusts, at best.  

[KoalaBeer]

4 minutes ago, hawkeye_wx said:

Yeah, pretty much all of them are stalling and weakening Florence somewhere along the coast of NC or SC.

Disgusting especially if the eye barely manages to make it onshore. The coastal impacts are going to be extreme with most of those. 

[jayson]

9 minutes ago, KoalaBeer said:

Disgusting especially if the eye barely manages to make it onshore. The coastal impacts are going to be extreme with most of those. 

It will be, but it will also be a blessing for interior NC/SC where they were showing 2-3 feet of rain this time yesterday. 

I am going to go out on a limb and say that if this blocking pattern sets up this strongly, I would expect Flo to weaken pretty significantly in the run-up to the coast, likely losing major hurricane status quickly.

[olafminesaw]

24 hour precipitation forecast: