Category Five Hurricane Lee

[GaWx]

 The 12Z UKMET is similar to recent runs with it moving N near 70W at 168.

[StantonParkHoya]

Those late September MDRs face so much pressure to recurve though 

[WxWatcher007]

8 minutes ago, StantonParkHoya said:

Those late September MDRs face so much pressure to recurve though 

Yep. Troughs galore this time of year. OTS is still squarely on the table, even as the potential for Atlantic Canada has increased. 

[GaWx]

3 minutes ago, WxWatcher007 said:

Yep. Troughs galore this time of year. OTS is still squarely on the table, even as the potential for Atlantic Canada has increased. 

I'm still near a 20% chance for a NE US landfall for now.

[Boston Bulldog]

3 hours ago, NeffsvilleWx said:

 

 

Cells are an average value of all their contents. If a cell has pressure values of 1024, 1028, 1010, 1015, and 948, then that cell will be given a value of 1005. Even though there's a 948 mb low in there.

There's probably some fancy math nuance to it that mets could chime in on, but I believe this is the gist of it (cell dimensions vary by model). 

 

Pretty spot on. Spatial gridding resolution for global model outputs are significantly more coarse than mesoscale models. This is especially true when compared to hurricane models like HWRF or HAFS that can "telescope" in on hurricanes and move with them in space and time with storm following nests.

Here is a great BAMS article on hurricane model "nesting" for those who want to learn more: https://journals.ametsoc.org/view/journals/bams/103/3/BAMS-D-20-0134.1.xml

Tight pressure gradients, such as the inner core of an intense hurricane, are on the subgrid scale and thus the model will interpolate values for given variables to fill the gap between grid points. Interpolation algorithms will not be able to correctly render the pressure gradient surrounding the MSLP of an exceptionally deep TC, hence why we see so many models initialize runs at significantly higher pressures.

[NJwx85]

12z HAFS brings Lee back up to Cat 5 intensity tomorrow, hitting ~155kts (175 MPH) at 03z Sunday before an ERC on Sunday/Monday which dramatically expands the wind field.

Current :

vs

 

[Wannabehippie]

Latest satellite photos appear to show the eye completely obscured, and that shear hitting Lee hard at the moment. Is the consensus that Lee will see a bit more weakening on the next NHC report?

[eyewall]

23 minutes ago, Wannabehippie said:

Latest satellite photos appear to show the eye completely obscured, and that shear hitting Lee hard at the moment. Is the consensus that Lee will see a bit more weakening on the next NHC report?

Overall yes. Lee definitely peaked last night.

INIT  08/2100Z 18.9N  55.5W  130 KT 150 MPH
 12H  09/0600Z 19.7N  56.9W  125 KT 145 MPH
 24H  09/1800Z 20.6N  58.6W  120 KT 140 MPH
 36H  10/0600Z 21.3N  60.0W  120 KT 140 MPH
 48H  10/1800Z 21.9N  61.3W  125 KT 145 MPH
 60H  11/0600Z 22.5N  62.5W  125 KT 145 MPH
 72H  11/1800Z 23.0N  63.7W  125 KT 145 MPH
 96H  12/1800Z 23.7N  66.0W  120 KT 140 MPH
120H  13/1800Z 25.1N  67.6W  110 KT 125 MPH

[so_whats_happening]

[Wannabehippie]

5:00 PM AST Fri Sep 8
Location: 18.9°N 55.5°W
Moving: WNW at 13 mph
Min pressure: 942 mb
Max sustained: 150 mph

[Sportybx]

When is he suppose to be making this move north ?!? 

[Wannabehippie]

5 minutes ago, Sportybx said:

When is he suppose to be making this move north ?!? 

I believe Tuesday or Wednesday it should start to move north, instead of WNW. But one of the pro forecasters can chime in on this one to confirm. 
Right now it will stay well off the east coast until at least Maine, or possibly Nova Scotia, at this point.

 

[Wannabehippie]

Two new recon flights headed to Lee. one NOAA, one AF. It will be interesting to see what they find. 

[NorthHillsWx]

30 minutes ago, so_whats_happening said:

Inner core then nothing. That’s not a healthy look

[so_whats_happening]

1 minute ago, NorthHillsWx said:

Inner core then nothing. That’s not a healthy look

It just updated with the last two hours and does show the core has taken a beating definitely feels like ERC is taking place lets see what happens overnight as the shear continues to relax overall it still is a pretty solid storm just needs to finish what most likely is wind expansion at this point. We may see a surge back to those levels earlier but would need to really deepen to do that. 

[GaWx]

 It looks like ~5 (10%) of the 12Z EPS members through hour 240 have a US landfall with all on ME. If there are no more after 240 (probably the case), that would mean a drop from the 14% US landfalls on the 0Z and the 24% on yesterday's 12Z, which had the most.

 So, assuming 10% is it for the 12z, here is the running EPS tally of US landfalls:

9/8 12Z: 5 (10%) 9/15-18 (5 ME)       

9/8 0Z: 7 (14%) 9/15-17 (6 ME, 1 NY)
9/7 12Z: 12 (24%) 9/15-19 (7 ME, 3 MA, 1 NY, 1 NJ)
9/7 0Z: 10 (20%) 9/15-18 (5 ME, 5 MA)
9/6 12Z: 3 (6%) 9/15-18 (2 ME, 1 MA)
9/6 0Z: 5 (10%)
9/5 12Z: 2 (4%)
9/5 0Z: 4 (8%) 
9/4 12Z: 1 (2%) 
9/4 0Z: 2 (4%)

 Based on the trend of the latest two EPS runs as well as overall model consensus trends, I'm dropping the chance for a US landfall from 20% to 10% and with that mostly for ME. I won't go lower because it is still 10% on the 12Z EPS and the 12Z GEFS also has 10% (3 members hit 9/15-18 with one on each of ME, MA, and RI). To go lower than 10% with any potential hit still 7-10 days away along with the 10% of ensemble members having hits would seem premature.

[StantonParkHoya]

Both the Euro and GFS showing a mighty close call on Bermuda. They need to be prepared.

[Wannabehippie]

19 minutes ago, so_whats_happening said:

It just updated with the last two hours and does show the core has taken a beating definitely feels like ERC is taking place lets see what happens overnight as the shear continues to relax overall it still is a pretty solid storm just needs to finish what most likely is wind expansion at this point. We may see a surge back to those levels earlier but would need to really deepen to do that. 

ERC plus shear is taking its toll. I am confident that once the shear lessens, the weakening trend will end. 

[Wannabehippie]

2 minutes ago, StantonParkHoya said:

Both the Euro and GFS showing a mighty close call on Bermuda. They need to be prepared.

Bermuda is such a tiny dot in the Atlantic, it is awful hard for it to get a direct hit. They have had brushes with powerful storms before, and are well prepared for these situations.

[CheeselandSkies]

Bermuda is such a tiny dot in the Atlantic, it is awful hard for it to get a direct hit. They have had brushes with powerful storms before, and are well prepared for these situations.

In 2019/20, direct hits (landfall from the latter) from Humberto and Paulette caused fairly heavy damage, but no deaths and not enough to warrant retirement.

Sent from my Pixel 4a using Tapatalk

[GaWx]

17 minutes ago, Wannabehippie said:

Bermuda is such a tiny dot in the Atlantic, it is awful hard for it to get a direct hit. They have had brushes with powerful storms before, and are well prepared for these situations.

 Due to very strict building codes as well as the vast majority of Bermuda being elevated well above even major storm surge levels (I've been there and thus have seen it firsthand), I wouldn't even feel all that worried if I were stuck there during a hurricane. I'd actually feel safer there than where I live.

 

Map of Bermuda showing hilly areas dominating:

https://www.worldatlas.com/maps/bermuda

[CoastalWx]

Atmospheric conditions are everything. You can have the Atlantic boiling and if shear or dry air is a factor, forget it. 

[NJwx85]

https://x.com/drewshearer444/status/1700290188189077964?s=46&t=wnL9UkNay47lChNZhqU2Pw

[STILL N OF PIKE]

11 minutes ago, CoastalWx said:

Atmospheric conditions are everything. You can have the Atlantic boiling and if shear or dry air is a factor, forget it. 

It’s too bad atmospheric conditions like shear  are sometimes too fickle (not able to be forecast well)  24 hours out in relation to a storms ability to sustain itself . It was Thought divergent flow aloft would offset the shear ...negative 

[WxWatcher007]

13 minutes ago, CoastalWx said:

Atmospheric conditions are everything. You can have the Atlantic boiling and if shear or dry air is a factor, forget it. 

 

2 minutes ago, STILL N OF PIKE said:

It’s too bad atmospheric conditions like shear  are sometimes too fickle (not able to be forecast well)  24 hours out in relation to a storms ability to sustain itself . It was Thought divergent flow aloft would offset the shear ...negative 

Obviously conditions were ideal 24 hours ago, but it’s clear from recon that shear absolutely rocked the inner core today. It may not even be a major hurricane right now. No guidance saw that coming.

That said, this may take off again once the shear abates. I wonder what’ll happen to the wind field when it tries to reorganize.

[STILL N OF PIKE]

6 minutes ago, WxWatcher007 said:

 

Obviously conditions were ideal 24 hours ago, but it’s clear from recon that shear absolutely rocked the inner core today. It may not even be a major hurricane right now. No guidance saw that coming.

That said, this may take off again once the shear abates. I wonder what’ll happen to the wind field when it tries to reorganize.

I’m more interested currently in what is the low point for Lee before it has the chance to reorganize better (according to most intensity / sheer forecasts ) sometime Sunday 

[WxWatcher007]

4 minutes ago, STILL N OF PIKE said:

It could also crap itself more than anticipated tonite , it may have to reorganize more than folks think by Sunday am . I think that may be a new wildcard given how tiny it’s inner core is , just erode that enough and ...seems to be at the mercy of fluctuations in shear that can’t be nailed down completely next 18-24 hrs 

Yeah not quite sure what to make of it. Every degree matters, especially since the trend has continued to be a more extended northward push. I don’t think this gets to 75W obviously…but some westward drift toward 70-71W could mean a greater chance of direct impacts in ENE/Atlantic Canada.

[Sportybx]

8 minutes ago, WxWatcher007 said:

Yeah not quite sure what to make of it. Every degree matters, especially since the trend has continued to be a more extended northward push. I don’t think this gets to 75W obviously…but some westward drift toward 70-71W could mean a greater chance of direct impacts in ENE/Atlantic Canada.

Was just watching a live meteorologist with live feed on Lee . they are saying the shear broke the backside off and now it isn’t moving Wnw anymore , it’s now moving due W . They weren’t expecting that to happen . 

[WxWatcher007]

3 minutes ago, Sportybx said:

Was just watching a live meteorologist with live feed on Lee . they are saying the sheer broke the backside off and now it isn’t moving Wnw anymore , it’s now moving due W . They weren’t expecting that to happen . 

It’s going to eventually turn northward—the trough is definitely going to erode the ridge, but as @STILL N OF PIKE said, this seems like a wildcard. Not sure why we haven’t had environmental sampling yet from recon. Plane issue?

Edit: also, watch the recon fixes. That’ll give us the realest sense of short term heading. Easy to be fooled by satellite, especially with a less organized storm.

[STILL N OF PIKE]

32 minutes ago, NJwx85 said:

https://x.com/drewshearer444/status/1700290188189077964?s=46&t=wnL9UkNay47lChNZhqU2Pw

958 mb . Just copied your post bc so many more see it when the tweet is embedded