ATL: DORIAN - Post-Tropical - Discussion

[Highteeld]

978mb/80kt is probably where i'd peg this thing rn

[Kingarabian]

980mb pressure and 80kt winds lines up with the traditional pressure/wind relationship better.

[flamingosun]

August 29, 2019
Port Canaveral at condition 'X-RAY' as Hurricane Dorian nears Florida
The U.S. Coast Guard Captain of the Port (COTP) has set Hurricane Condition "X-RAY" for Port Canaveral. Sustained gale-force winds are predicted within 48 hours.

Edit to add link and explanation
LINK https://www.portcanaveral.com/About/Recent-News
CONDITION XRAY means that gale force winds are possible within 48 hours. The port currently remains open to all commercial traffic, but oceangoing ships and barges must report their intention to remain in port or depart. If they are departing, they must do so within 12 hours of gale-force winds.

[1900hurricane]

So it's weakening, since the wind speed was previously 85? I guess that's good news although it has several days of a good environment ahead of it.

80 kt = 90 mph. That would be a slight wind increase, but a big pressure decrease.

Fortunately the models don't show very high winds despite the low pressure when it makes landfall. High resolution Euro has 80kt 10m winds while the GFS is near 92-95kts. This is sort of reflected on this pass. Maybe 1900Hurricane can explain further.

Disclaimer: The Euro and GFS are probably too low on the wind speed.

I couldn't tell you for sure, but I do have an idea. I think it's likely that due to limitations involving grid resolution and model physics, the operational models we use now can't actually properly resolve either the pressure gradient itself or the airmass response to the gradient. NWP has come a long way, but grid spacing is still on the order of kilometers. In tight pressure gradient regions like an eyewall, it's possible not everything can be captured.

[1900hurricane]

00Z is 80 kt/978 mb.

[Astromanía]

This thing looks bad, I really wonder if it will insensify later

[AxaltaRacing24]

This thing looks bad, I really wonder if it will insensify later

It's already happening. Down 8mb and up to 90mph now.

[1900hurricane]

980mb pressure and 80kt winds lines up with the traditional pressure/wind relationship better.

Yep, lining up much better right now. Here are my KZC rips using r34 and rOCI, respectively. I'm curious to see how the pressure/wind relationship progresses from here though, since it seems to still be in quasi-eyewall replacement mode. Will it keep closer to expected KZC values now or will it deviate again?

System: 05L DORIAN
Date & Time Lat/Lon Vmax Speed Mean Presssure OCI
(kt) (kt) r34 exp (act)
--------------------------------------------------------------------------------
8/22/2019 12Z: 9.5N 35.9W 15, 5, 0, 1002 (1009), 1002
8/22/2019 18Z: 9.5N 37.3W 15, 14, 0, 1002 (1009), 1002
8/23/2019 0Z: 9.5N 39.0W 20, 17, 0, 1002 (1009), 1002
8/23/2019 6Z: 9.6N 40.4W 20, 14, 0, 1013 (1012), 1013
8/23/2019 12Z: 9.8N 41.7W 25, 13, 0, 1014 (1012), 1014
8/23/2019 18Z: 10.0N 43.5W 25, 18, 0, 1014 (1012), 1014
8/24/2019 0Z: 10.2N 45.3W 25, 18, 0, 1014 (1012), 1014
8/24/2019 6Z: 10.3N 46.4W 25, 11, 0, 1014 (1011), 1015
8/24/2019 12Z: 10.4N 47.5W 30, 11, 0, 1011 (1010), 1014
8/24/2019 18Z: 10.6N 48.7W 35, 12, 10, 1009 (1008), 1014
8/25/2019 0Z: 10.8N 49.9W 35, 12, 10, 1009 (1008), 1014
8/25/2019 6Z: 11.0N 51.0W 40, 11, 10, 1007 (1007), 1014
8/25/2019 12Z: 11.1N 52.3W 40, 13, 10, 1007 (1006), 1014
8/25/2019 18Z: 11.4N 53.5W 45, 12, 15, 1006 (1005), 1015
8/26/2019 0Z: 11.6N 54.7W 45, 12, 32, 1003 (1004), 1012
8/26/2019 6Z: 11.8N 55.9W 50, 12, 32, 1000 (1002), 1012
8/26/2019 12Z: 12.1N 57.1W 50, 12, 32, 1000 (1002), 1012
8/26/2019 18Z: 12.6N 58.3W 45, 13, 28, 1003 (1004), 1012
8/27/2019 0Z: 13.0N 59.2W 45, 10, 28, 1002 (1004), 1012
8/27/2019 6Z: 13.5N 60.2W 45, 11, 28, 1003 (1005), 1012
8/27/2019 12Z: 14.0N 61.3W 45, 12, 28, 1003 (1005), 1012
8/27/2019 18Z: 15.0N 62.0W 45, 12, 28, 1003 (1005), 1012
8/28/2019 0Z: 15.8N 62.7W 50, 10, 28, 1000 (1003), 1012
8/28/2019 6Z: 16.4N 63.5W 55, 10, 28, 997 (1002), 1012
8/28/2019 12Z: 17.1N 64.1W 60, 9, 30, 994 ( 999), 1012
8/28/2019 18Z: 18.3N 65.1W 65, 15, 32, 991 ( 997), 1012
8/29/2019 0Z: 19.2N 65.7W 70, 11, 35, 986 ( 990), 1012
8/29/2019 6Z: 20.0N 66.4W 75, 10, 50, 982 ( 991), 1012
8/29/2019 12Z: 21.0N 66.9W 75, 11, 50, 981 ( 987), 1012
8/29/2019 18Z: 22.0N 67.4W 75, 11, 55, 981 ( 986), 1012
8/30/2019 0Z: 22.8N 68.0W 80, 10, 60, 976 ( 978), 1012
--------------------------------------------------------------------------------

System: 05L DORIAN
Date & Time Lat/Lon Vmax Speed Mean Presssure OCI
(kt) (kt) rOCI exp (act)
--------------------------------------------------------------------------------
8/22/2019 12Z: 9.5N 35.9W 15, 5, 0, 0 (1009), 0
8/22/2019 18Z: 9.5N 37.3W 15, 14, 0, 0 (1009), 0
8/23/2019 0Z: 9.5N 39.0W 20, 17, 0, 0 (1009), 0
8/23/2019 6Z: 9.6N 40.4W 20, 14, 90, 1013 (1012), 1013
8/23/2019 12Z: 9.8N 41.7W 25, 13, 90, 1014 (1012), 1014
8/23/2019 18Z: 10.0N 43.5W 25, 18, 90, 1014 (1012), 1014
8/24/2019 0Z: 10.2N 45.3W 25, 18, 90, 1014 (1012), 1014
8/24/2019 6Z: 10.3N 46.4W 25, 11, 130, 1015 (1011), 1015
8/24/2019 12Z: 10.4N 47.5W 30, 11, 120, 1012 (1010), 1014
8/24/2019 18Z: 10.6N 48.7W 35, 12, 110, 1010 (1008), 1014
8/25/2019 0Z: 10.8N 49.9W 35, 12, 100, 1010 (1008), 1014
8/25/2019 6Z: 11.0N 51.0W 40, 11, 100, 1008 (1007), 1014
8/25/2019 12Z: 11.1N 52.3W 40, 13, 100, 1008 (1006), 1014
8/25/2019 18Z: 11.4N 53.5W 45, 12, 100, 1007 (1005), 1015
8/26/2019 0Z: 11.6N 54.7W 45, 12, 100, 1003 (1004), 1012
8/26/2019 6Z: 11.8N 55.9W 50, 12, 100, 1001 (1002), 1012
8/26/2019 12Z: 12.1N 57.1W 50, 12, 100, 1001 (1002), 1012
8/26/2019 18Z: 12.6N 58.3W 45, 13, 120, 1003 (1004), 1012
8/27/2019 0Z: 13.0N 59.2W 45, 10, 120, 1003 (1004), 1012
8/27/2019 6Z: 13.5N 60.2W 45, 11, 120, 1003 (1005), 1012
8/27/2019 12Z: 14.0N 61.3W 45, 12, 120, 1003 (1005), 1012
8/27/2019 18Z: 15.0N 62.0W 45, 12, 120, 1003 (1005), 1012
8/28/2019 0Z: 15.8N 62.7W 50, 10, 120, 1000 (1003), 1012
8/28/2019 6Z: 16.4N 63.5W 55, 10, 120, 997 (1002), 1012
8/28/2019 12Z: 17.1N 64.1W 60, 9, 120, 994 ( 999), 1012
8/28/2019 18Z: 18.3N 65.1W 65, 15, 120, 991 ( 997), 1012
8/29/2019 0Z: 19.2N 65.7W 70, 11, 100, 987 ( 990), 1012
8/29/2019 6Z: 20.0N 66.4W 75, 10, 110, 982 ( 991), 1012
8/29/2019 12Z: 21.0N 66.9W 75, 11, 120, 982 ( 987), 1012
8/29/2019 18Z: 22.0N 67.4W 75, 11, 110, 982 ( 986), 1012
8/30/2019 0Z: 22.8N 68.0W 80, 10, 100, 978 ( 978), 1012
--------------------------------------------------------------------------------

[LarryWx]

As I’ve said, don’t be surprised if the FL-NC rainfall ends up being as big a story from this storm as any aspect. I mean those 10-20”+ amounts from FL to NC on the 18Z GFS probably cover some 20K miles (that’s 2/3 the size of the state of SC). I was checking some other SE storms like Easy, Floyd, Joaquin, Florence, Alberto, and Matthew. Based on this, I think that the 18Z GFS might be making it close to a record dumping for one storm in the SE. It is possible that only Florence would exceed this model run. What’s amazing is that Dorian isn’t even projected to be a big storm! Besides the very slow movement, very important heavy rain favoring factors are very low shear persisting through its inland track and very warm SSTs/dewpoints. (Harvey isn’t a SE storm. So, it isn’t being considered. This wouldn’t get close to Harvey, which may be a 1 in 1000 year event.)

[Kingarabian]

Maybe wind speed up to 85kts.

[beachman80]

One major reason why EVERYONE in Florida needs to still be paying attention on this, even those on the west coast who think they are out of the woods with a direct hit.....

If you go through the Irma graphics archive and stop it at 11am Thursday when it was north of Hispanola, the NHC projected the Euro scenario just 70 hours out before it made landfall. The storm ended up on the left edge of the cone hitting the west coast, not the east coast.

https://www.nhc.noaa.gov/archive/2017/I ... _with_line

[Kat5]

Can’t hardly make out that ULL west of Dorian, might be weakening faster than the models have predicted.

[1900hurricane]

Maybe wind speed up to 85kts.

Looks pretty convincing so far. No weird jumps or skips or anything in the data. Both flight level winds and SFMR support it.

[NDG]

NOAA recon finds 94 knots flight level winds in the NE quadrant.

94 knots
(~ 108.2 mph)

[CrazyC83]

Combined with earlier SFMR data, I think 85 kt might be a good estimate now.

[MetroMike]

One major reason why EVERYONE in Florida needs to still be paying attention on this, even those on the west coast who think they are out of the woods with a direct hit.....

If you go through the Irma graphics archive and stop it at 11am Thursday when it was north of Hispanola, the NHC projected the Euro scenario just 70 hours out before it made landfall. The storm ended up on the left edge of the cone hitting the west coast, not the east coast.

https://www.nhc.noaa.gov/archive/2017/I ... _with_line

Great example of track changes several days out.
The news media doesn’t help this situation.

[ScottNAtlanta]

977.5 on the last pass just now, and the other plane had 85kts but isnt at the center yet

[Chris90]

There's very recently been an unflagged 91kt SFMR reading come in as well. Winds definitely seem to be responding to the pressure drops now.

[Kingarabian]

Very impressive that it's still deepening despite taking hits from shear. Eastern portion of the system is flattening as well now, evidence of some shear.

[CrazyC83]

There's very recently been an unflagged 91kt SFMR reading come in as well. Winds definitely seem to be responding to the pressure drops now.

No doubt it is a category 2 storm now. They might go 90 kt on that.