Florence

Gaoth Laidir

18Z GMI 37 GHz (lower structure) and 89 GHz (upper structure). The larger eye diameter is striking.





Ocean Heat Content will be at a max in the next 12 hours, hence the peak intensity then. After that its slower speed will churn up cooler water from that shallower OCH, which will hopefully cause decent weakening before landfall. Remember, the max winds only occur in a very small area of one part of the storm, just a couple of miles across. 64+ kts up to around 50 NM, but there's a big difference between 64 and 100+ kts. I still say a Cat 3 landfall.



Latest multiplatform winds. Vmax 112 kts 23 NM north of the centre.

Kermit.de.frog

Fascinating observing the changes today!

Recon mission 9 is en-route - should get intermediate advisory update around 1 am.

https://twitter.com/NYCAviation/status/1039494498139758592

Gonzo and Kermit - I giggled :pac:

P.S look for a tightening of the eye walls for sure sign of further intensifying.

sdanseo

Kermit.de.frog wrote: »

Fascinating observing the changes today!

Recon mission 9 is en-route - should get intermediate advisory update around 1 am.

https://twitter.com/NYCAviation/status/1039494498139758592

Gonzo and Kermit - I giggled :pac:

Over 43 years old and still being regularly flown through Cat 5 hurricanes.
Kermit here in Shannon

https://www.jetphotos.com/photo/8865397

Meteorite58

Looking like a Cat 3 at landfall all right ( possibly high end ). Big threat of stalling.


NHC

FORECAST POSITIONS AND MAX WINDS

INIT 11/2100Z 27.5N 67.1W 120 KT 140 MPH
12H 12/0600Z 28.7N 69.3W 130 KT 150 MPH
24H 12/1800Z 30.4N 72.1W 135 KT 155 MPH
36H 13/0600Z 32.1N 74.5W 130 KT 150 MPH
48H 13/1800Z 33.4N 76.2W 120 KT 140 MPH
72H 14/1800Z 34.5N 77.7W 100 KT 115 MPH...NEAR THE COAST
96H 15/1800Z 35.0N 78.8W 40 KT 45 MPH...INLAND
120H 16/1800Z 35.7N 81.7W 25 KT 30 MPH...INLAND

sdanseo

Meteorite58 wrote: »

Looking like a Cat 3 at landfall all right ( possibly high end ). Big threat of stalling.


NHC

A degree of longitude is 60nm - so it'll move barely ~300nm in 4 days

Gaoth Laidir

SSMI scan just 40 mins ago, showing some variation still going on in the eyewall. Precipitation rates in the second image.

00Z SHIPS LGEM.

99 kts at +60 hrs with 14 kts of shear. Inland by 4km at that predicted point so one could call it landfall I suppose. Speed of system is a very slow 3 kts. 99 kts mightn't seem the strongest ever, but it will be a long period of stormy conditions.

ftp://ftp.nhc.noaa.gov/atcf/stext/18091200AL0618_ships.txt

GOES-16 shot of Florence on the move.

Kermit.de.frog

Latest recon shows no real intensification since the last flight. Core SLP reduced slightly to 944hpa

Chances of this hitting CAT 5 are (thankfully) diminishing fast now. One impediment seems to be incursions of dry air. Latest fly through shows 37% RH @ 700mb on the southwest side.

The system is being impeded from exploding at the moment.

That said things can change very fast as it's entering prime atmospheric conditions now.

They will do another pass through the eye but as you can see the northwest section is in much better shape.

Kermit.de.frog

The maximum surface level wind through mission 9 just now recorded was 121 MPH which makes her a CAT 3 hurricane.

New advisory keeps her at CAT 4 and 140 MPH.

That's just not correct right now.

Kermit.de.frog

Based on IR the storm looks to be intensifying now and we have finally lost the dry air incursion and the outflow has improved markedly on the southwest side. There could be rapid intensification in the next few hours.

Gaoth Laidir

Yes, the highest SFMR surface winds measured in Mission 9 were 107 knots on a couple of passes, most recently 103 kts in the past 40 minutes. Multiplatform winds at 03Z agree with this, showing Vmax of 112 kts just to the north of the centre. The 10 am update should reflect this lower intensity.



That dry air is evident on the latest wv and has been for some time.



Can see it wrapping in on the latest 89 GHz microwave too.

Graces7

These images are frankly terrifying. Shivers.. Hoping the residents have the sense to evacuate.

Gaoth Laidir

Sunny Point won't be so sunny...



Florence will pass close to Buoy 41047, which is currently 195 NM west of the centre. Pressure dropping and wind rising there now.

Gaoth Laidir

Current ADT estimate is 109.8 kts.

http://tropic.ssec.wisc.edu/real-time/adt/odt06L.html

All the data agree on some weakening to Cat 3 overnight, but we'll see what the NHC say at 10 am. To mention weakening at this stage would probably affect the evacuation process so they may keep the intensity up again, as they've done before.

Kermit.de.frog

Looking much healthier on IR and Dvorak now - unfortunately won't be a recon in the area for a little while.

Definite intensification ongoing.

Kermit.de.frog

Really getting it's act in gear now. Cloud tops cooling far beyond the eye.

Gaoth Laidir

Kermit.de.frog wrote: »

Really getting it's act in gear now. Cloud tops cooling far beyond the eye.

It's still a bit fragmented on its western side. ADT AT 0615Z still only 112 kts.

This is the chart of the latest recon.

Kermit.de.frog

Intensification has occurred after mission 9.

I could be wrong but IR and Dvorak would suggest not! It's looking impressive now.

Ironically the next update could underplay it somewhat.

sdanseo

I notice on the 11pm/ 3Z am update they dropped the word “extremely” before “dangerous major hurricane”.

Subtle but not accidental? A scientisists way of making sure the update was reflective of the slight weakening despite probably being officially told to keep it at Cat 4?

Or am I just a conspiracy theorist 😂

Gaoth Laidir

Latest NHC intensity now has it down to 115 knots. Still above actual Mission 9 data but probably to allow for some undersampling, though it did make 3 passes through the eye, the latest of which showed 103 kts. Latest Dvorak and multiplatform winds 112 kts.

The 06Z SHIPS LGEM has it at 105 kts in 48 hrs 55 km from landfall and on a weakening trend. Still reckon low-mid Cat 3 landfall.

Gaoth Laidir

sdanseo wrote: »

I notice on the 11pm/ 3Z am update they dropped the word “extremely” before “dangerous major hurricane”.

Subtle but not accidental? A scientisists way of making sure the update was reflective of the slight weakening despite probably being officially told to keep it at Cat 4?

Or am I just a conspiracy theorist 😂

They definitely so tend to err on the generous side intensity-wise in the final couple of days before landfall.

Gaoth Laidir

SSMI 89 GHz and 37 GHz at 0806Z shows a nice structure again, with the first sight of land visible to the far northwest.





Latest Dvorak estimate 119 kts.

Villain

The Category at land fall may not be as relevant as usual, the main issue here looks to be surge and rainfall with that ridge blocking it the rainfall of up to 40 inches is likely the biggest issue.

star gazer

Graphics archive

That very slow movement just offshore for a day or more on the NHC track and other models could put a lot of rain onto a concentrated area as mentioned above. Also depending on timing, high tide could add to the initial storm surge but with the size of Florence and the fact it'll be just offshore for a while means that there'll be impacts coinciding with high tide at some point.

Gaoth Laidir

12Z intensity still 115 kts. It's surrounded by dry mid-level air. The 12Z SHIPS LGEM now shows no landfall (at least for its forecast hours), with the closest to land 7 km at 60 hours and 25 km again at 72 hrs.

Hour...Land (km)...Vmax (kt)
48..........34...............101......
60...........7..................92......
72..........25.................85......

Oneiric 3

German MO analysis at 12z, central pressure down to 946 hPa:

Itssoeasy

Georgia has declared a state of Emergency as the hurricanes track is showing it drifting south west(?) of the carolinas.

Gaoth Laidir

Oneiric 3 wrote: »

German MO analysis at 12z, central pressure down to 946 hPa:

Wait, what land is that?

Itssoeasy

Gaoth Laidir wrote: »

Wait, what land is that?

Oh yeah the land is on the wrong side isn't it. The east coast of the US should be on the left as the hurricane is moving from right to left isn't it ?