ATL: FLORENCE - Post-Tropical - Discussion

[Rail Dawg]

Very warm and moist here in Wilmington.

You can just feel the fuel for this hurricane.

The parking garage I’m in is starting to fill up.

Things are starting to pick up as far as people scurrying to make final preps.

No more fuel here in town although not sure if any tankers will come in as storm is still 36+ hours out.

I’ve got a great vantage point if I go to the 8th floor of the garage.

[PTPatrick]

Couple of things... some models still try to deepen this toward landfall over the Gulf Stream...despite its repeated failed attempts at running into high cat 4/5 territory, it seems cat 4 near land isn’t off the table yet.

The other side of that argument...I think and storm with this wide of an eye will struggle to go up much above cat 3. But I think we are sort of in uncharted territory so who knows. Most storms with these huge eyes are in the weakening stages. Will be interesting to see if she can maintain her plus sized eye and strengthen or if she just stays in perpetual ERC mode until degradation near land.

[supercane4867]

Concentric eyewall structure is clearly visible now. The outer eyewall appears to be about 140 miles wide

[Ken711]

I know someone else asked this question but hoping one of the smart peeps - well smarter than me at least - can translate this from the 11 am discussion. Thanks in advance

The
shortwave trough over the southern Plains seen in water vapor
imagery could end up being a significant factor as it rounds the
narrow ridge over the Tennessee Valley and is expected to erode the
ridge along the U.S. mid-Atlantic coast on days 3-5. At this time,
little change has been made to the NHC track forecast, which remains
very close to the aforementioned consensus aids through 72 hours.

This is why I asked it earlier as to what it does to the track after 72 hours.

[StormPyrate]

EWR is so interesting, I always thought this happened due to the eyewall tightening until it was to small to sustain and a new larger more stable eyewall replaced it.
But this eyewall has stayed in the 30ish mile diameter since it completed yesterday.
So since this one has not tightened and another seems to be forming, is this maybe not an eyewall replacement, but a storm literally developing a multiple eye wall structure? or is that even a thing?

Sorry still learning
G. Eye Shape & Diameter: Circular with a diameter of 28 nautical miles (32 statute miles)

For those without a decoder implanted in their brains.
Dewpoint increasing, another marker of an EWRC

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 12th day of the month at 15:26Z


A. Time of Center Fix: 12th day of the month at 14:57:20Z
B. Center Fix Coordinates: 29.93N 71.35W
D. Minimum Sea Level Pressure: 947mb (27.97 inHg)
F. Eye Character: Open in the south
G. Eye Shape & Diameter: Circular with a diameter of 28 nautical miles (32 statute miles)
H. Estimated (by SFMR or visually) Maximum Surface Wind Inbound: 99kts (113.9mph)
I. Location & Time of the Estimated Maximum Surface Wind Inbound: 21 nautical miles (24 statute miles) to the NE (53°) of center fix at 14:51:00Z
J. Maximum Flight Level Wind Inbound: From 138° at 123kts (From the SE at 141.5mph)
K. Location & Time of the Maximum Flight Level Wind Inbound: 24 nautical miles (28 statute miles) to the NE (52°) of center fix at 14:50:00Z
L. Estimated (by SFMR or visually) Maximum Surface Wind Outbound: 82kts (94.4mph)
M. Location & Time of the Estimated Maximum Surface Wind Outbound: 23 nautical miles (26 statute miles) to the SW (233°) of center fix at 15:14:30Z
N. Maximum Flight Level Wind Outbound: From 305° at 87kts (From the NW at 100.1mph)
O. Location & Time of the Maximum Flight Level Wind Outbound: 7 nautical miles to the WSW (245°) of center fix at 15:09:30Z
P. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 10°C (50°F) at a pressure alt. of 3,049m (10,003ft)
Q. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 16°C (61°F) at a pressure alt. of 3,047m (9,997ft)
R. Dewpoint Temp (collected at same location as temp inside eye): 15°C (59°F)

Remarks Section:

Maximum Flight Level Wind: 123kts (~ 141.5mph) which was observed 24 nautical miles (28 statute miles) to the NE (52°) from the flight level center at 14:50:00Z

[supercane4867]

Huh?

 https://twitter.com/RawStory/status/1039887723157442560

[StormPyrate]

Wave height up 2 feet in one hour at this buoy
https://www.ndbc.noaa.gov/station_page. ... tion=41002

[meriland29]

Huh?

https://twitter.com/RawStory/status/1039887723157442560

..yeah, when it comes to Darwinism..

[BensonTCwatcher]

Very warm and moist here in Wilmington.

You can just feel the fuel for this hurricane.

The parking garage I’m in is starting to fill up.

Things are starting to pick up as far as people scurrying to make final preps.

No more fuel here in town although not sure if any tankers will come in as storm is still 36+ hours out.

I’ve got a great vantage point if I go to the 8th floor of the garage.

Which Garage are you in? I boarded up yesterday and secured the boat ( more like bid it farewell near Carolina Beach.) Interested to see what the surge is up the river as well. During Mathew it was up to the steps of the courthouse on water street and covered the battleship park parking area.

[psyclone]

Huh?

https://twitter.com/RawStory/status/1039887723157442560

..yeah, when it comes to Darwinism..

well...there is strength in numbers....like 950mb pressure, 10 feet of storm surge, 2 feet of rain, 20 foot waves and 100mph winds.

[ozonepete]

I know someone else asked this question but hoping one of the smart peeps - well smarter than me at least - can translate this from the 11 am discussion. Thanks in advance

The
shortwave trough over the southern Plains seen in water vapor
imagery could end up being a significant factor as it rounds the
narrow ridge over the Tennessee Valley and is expected to erode the
ridge along the U.S. mid-Atlantic coast on days 3-5. At this time,
little change has been made to the NHC track forecast, which remains
very close to the aforementioned consensus aids through 72 hours.

This is why I asked it earlier as to what it does to the track after 72 hours.

For both of you:
What it means is that an approaching trough weakens a ridge as it moves into it. This one will get to the Appalachians by Saturday. Since this is a shortwave trough it won't doesn't extend all the way south to the GOM but the bottom of this U-shaped feature should reach down to near northern GA and AL as it nears the Appalachians. This could weaken the strong blocking ridge enough to allow Florence to move northward inland along the Appalachinas after it has stalled out somewhere over the Carolinas and weakened. It has tremendous impact on how much flooding occurs if it can pick up the remnants and kick them north. Would be less flooding inland, hopefully but highly uncertain at this early point.

[Coaster]

The National Hurricane Center's Hurricane Florence forecast discussion Number 53 1100 AM EDT Wed Sep 12 2018 narrative states as Hurricane Florence approaches the Carolina coast decreasing ocean heat content should cause cold Upwelling beneath Hurricane Florence which should induce a gradual weakening trend.

The Gulf Stream flows at approximately 4 mph and transports nearly four billion cubic feet of 80 plus degree water per second along the Carolina coast.

Wouldn't the Gulf Stream the warm water flow negate the affects of Upwelling?

Coaster

[robbielyn]

Huh?

https://twitter.com/RawStory/status/1039887723157442560

..yeah, when it comes to Darwinism..

Probably has no idea what these hurricanes can do. doesn’t sound like a native. there r two types of people. Wise and foolish. one doesn’t need to go to the school of hard knocks to see that the officials know what they are talking about. hope those innocent kids survive.

[Ken711]

I know someone else asked this question but hoping one of the smart peeps - well smarter than me at least - can translate this from the 11 am discussion. Thanks in advance

The
shortwave trough over the southern Plains seen in water vapor
imagery could end up being a significant factor as it rounds the
narrow ridge over the Tennessee Valley and is expected to erode the
ridge along the U.S. mid-Atlantic coast on days 3-5. At this time,
little change has been made to the NHC track forecast, which remains
very close to the aforementioned consensus aids through 72 hours.

This is why I asked it earlier as to what it does to the track after 72 hours.

For both of you:
What it means is that an approaching trough weakens a ridge as it moves into it. This one will get to the Appalachians by Saturday. Since this is a shortwave trough it won't doesn't extend all the way south to the GOM but the bottom of this U-shaped feature should reach down to near northern GA and AL as it nears the Appalachians. This could weaken the strong blocking ridge enough to allow Florence to move northward inland along the Appalachinas after it has stalled out somewhere over the Carolinas and weakened. It has tremendous impact on how much flooding occurs if it can pick up the remnants and kick them north. Would be less flooding inland, hopefully but highly uncertain at this early point.

Thank you for the explanation.

[meriland29]

The National Hurricane Center's Hurricane Florence forecast discussion Number 53 1100 AM EDT Wed Sep 12 2018 narrative states as Hurricane Florence approaches the Carolina coast decreasing ocean heat content should cause cold Upwelling beneath Hurricane Florence which should induce a gradual weakening trend.

The Gulf Stream flows at approximately 4 mph and transports nearly four billion cubic feet of 80 plus degree water per second along the Carolina coast.

Wouldn't the Gulf Stream the warm water flow negate the affects of Upwelling?

Coaster

I was thinking the same, but also take into consideration there will be some sheer as well.

[supercane4867]

The National Hurricane Center's Hurricane Florence forecast discussion Number 53 1100 AM EDT Wed Sep 12 2018 narrative states as Hurricane Florence approaches the Carolina coast decreasing ocean heat content should cause cold Upwelling beneath Hurricane Florence which should induce a gradual weakening trend.

The Gulf Stream flows at approximately 4 mph and transports nearly four billion cubic feet of 80 plus degree water per second along the Carolina coast.

Wouldn't the Gulf Stream the warm water flow negate the affects of Upwelling?

Coaster

The shelf waters along the coast are much shallower. Flo is expected to stall right over the coast in stead of over gulfstream which will cause a combination of upwelling and land interaction to weaken her in a faster pace.

[ronjon]

Couple of things... some models still try to deepen this toward landfall over the Gulf Stream...despite its repeated failed attempts at running into high cat 4/5 territory, it seems cat 4 near land isn’t off the table yet.

The other side of that argument...I think and storm with this wide of an eye will struggle to go up much above cat 3. But I think we are sort of in uncharted territory so who knows. Most storms with these huge eyes are in the weakening stages. Will be interesting to see if she can maintain her plus sized eye and strengthen or if she just stays in perpetual ERC mode until degradation near land.

Not sure it will matter much with these large storms - am thinking of Katrina that had weakened to a CAT 2 upon landfall yet still generated this massive surge.

[meriland29]

The National Hurricane Center's Hurricane Florence forecast discussion Number 53 1100 AM EDT Wed Sep 12 2018 narrative states as Hurricane Florence approaches the Carolina coast decreasing ocean heat content should cause cold Upwelling beneath Hurricane Florence which should induce a gradual weakening trend.

The Gulf Stream flows at approximately 4 mph and transports nearly four billion cubic feet of 80 plus degree water per second along the Carolina coast.

Wouldn't the Gulf Stream the warm water flow negate the affects of Upwelling?

Coaster

The shelf waters along the coast are much shallower. Flo is expected to stall right over the coast in stead of over gulfstream which will cause a combination of upwelling and land interaction to weaken her in a faster pace.

BUT...she is also moving forward much slower now..which could effect where she stalls out.....

[BobHarlem]

Seeing this graphic being posted around social media:



The uncolored map is the most misleading thing I've seen. Local mets in Florida seem to be freaking out about it (about this being misleading since it doesn't show probabilities.

[MaineWeatherNut]

It's been a while since the East Coast saw a potential Catastrophe like we could be watching about to unfold. I really hope everyone along the coast and even in land are paying close attention and taking the threat seriously!

Here is my latest update on Florence:
https://youtu.be/jkyAIbg_I5w