Jump to content
  • Member Statistics

    17,507
    Total Members
    7,904
    Most Online
    SnowHabit
    Newest Member
    SnowHabit
    Joined

Major Hurricane Larry


WxWatcher007
 Share

Recommended Posts

2 hours ago, Windspeed said:

Larry's size is now what is impressive here. Yeah, yadda yadda Cat 5 stuff. But this is a true beastly maritime cyclone, period. Ridiculous long period wave heights being generated by this monster. This is the stuff of nightmares for shipping interests.
ccba4d7814ad5f743a4a4f64dad7d3af.gif
 

How deep is the water there?

Link to comment
Share on other sites

Hurricane Larry Intermediate Advisory Number 34A
NWS National Hurricane Center Miami FL       AL122021
200 AM AST Thu Sep 09 2021

...LARRY'S OUTER BANDS APPROACHING BERMUDA...
...HURRICANE AND TROPICAL STORM WATCHES ISSUED FOR SOUTHEASTERN 
NEWFOUNDLAND...


SUMMARY OF 200 AM AST...0600 UTC...INFORMATION
----------------------------------------------
LOCATION...30.3N 60.8W
ABOUT 275 MI...440 KM ESE OF BERMUDA
MAXIMUM SUSTAINED WINDS...100 MPH...155 KM/H
PRESENT MOVEMENT...NNW OR 330 DEGREES AT 16 MPH...26 KM/H
MINIMUM CENTRAL PRESSURE...969 MB...28.62 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The Canadian Hurricane Centre has issued a Hurricane Watch for 
southeastern Newfoundland from St. Schotts northward to Pouch Cove.
A Tropical Storm Watch has been issued from Lamaline to west of St. 
Schotts and from north of Pouch Cove to Bonavista

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Hurricane Watch is in effect for...
* Southeastern Newfoundland from St. Schotts to Pouch Cove

A Tropical Storm Warning is in effect for...
* Bermuda

A Tropical Storm Watch is in effect for...
* Southeastern Newfoundland from Lamaline to west of St. Schotts
* Southeastern Newfoundland from north of Pouch Cove to Bonavista
Link to comment
Share on other sites

Interesting re the bolded in the 11pm disco

Hurricane Larry Discussion Number  34
NWS National Hurricane Center Miami FL       AL122021
1100 PM AST Wed Sep 08 2021

The infrared satellite presentation of Larry this evening is giving 
the false impression of a well-organized hurricane, with a ring of 
colder cloud tops (-65 to -70 C) and a warm spot within. However, we 
are fortunate to have in-situ data provided by an Air Force 
Reconnaissance Hurricane Hunter mission investigating Larry this 
evening. Their observations show that Larry's center is actually 
southwest of the warm spot seen on satellite. In fact, the plane was 
unable to identify an eye with Larry, and the highest flight-level 
and SFMR winds were found nearly 80 nautical miles away from the 
center. Moreover, there remains a large discrepancy between the peak 
700-mb flight level winds (108-kt) versus the much lower SFMR peak 
values (67-kt). This suggests that the 90 percent reduction factor 
that is typically applied to 700-mb flight level winds in the 
eyewall may not be appropriate for this hurricane given its very 
large radius of maximum winds more associated with weaker outer 
convection. Given these factors, the latest NHC initial intensity 
has been lowered to 85 kt for this advisory. This intensity is also 
a good compromise between the SAB and TAFB subjective Dvorak 
estimates. 

The hurricane's heading is still off to the northwest with the 
latest motion at 330/14 kt. The track forecast philosophy has not 
changed much for the last few days, with Larry moving around the 
western periphery of a deep-layer subtropical anticyclone over the 
central Atlantic. The hurricane should make its closest approach to 
the east of Bermuda tomorrow as it gradually turns north-northwest 
and north. After that, the hurricane will begin to dramatically 
accelerate to the northeast as Larry is picked up by a deep-layer 
trough moving offshore of the eastern United States. The latest 
forecast track is quite similar to the previous one, and takes Larry 
across the southeast portion of Newfoundland in 48-60 hours. The 
official forecast remains close to the tightly clustered track 
guidance consensus. 

The current structure of Larry appears to be somewhat tilted with 
height, with the low-level center identified by recon located to the 
southwest of the apparent center on IR satellite. While the shear as 
diagnosed by SHIPS appears to be lower, it appears dry air has 
significantly disrupted Larry's inner core structure, to the point 
that it likely will be unable to take advantage of the more 
favorable conditions. The latest NHC intensity forecast is lower 
than the previous one, owing to the lower initial intensity, but 
begins to show more pronounced weakening after 24 hours when the 
hurricane will accelerate poleward of the northern wall of the Gulf 
Stream. However, Larry is still forecast to be a hurricane as it 
passes near or over Newfoundland, though likely beginning to 
undergo extratropical transition. The models continue to maintain 
Larry as a large formidable cyclone after extratropical transition 
is complete while it moves into the far north Atlantic east of 
Greenland. This cyclone will eventually merge with another 
extratropical cyclone by the end of the forecast period.

Key Messages:

1. Large swells generated by Larry will continue to affect the
Leeward Islands, portions of the Greater Antilles, the
Bahamas, Bermuda, and the east coast of the United States and
Atlantic Canada through the end of the week. These swells will
likely cause life-threatening surf and rip current conditions, and
beachgoers and other interests along these coasts are urged to
follow the guidance of lifeguards and local officials this week.

2. The center of Larry is forecast to pass east of Bermuda on
Thursday, but given Larry's large size, tropical storm conditions
are expected there on Thursday, along with a risk of coastal
flooding.  A Tropical Storm Warning is in effect for Bermuda, and
interests there should closely monitor the latest forecast updates.

3. Larry is forecast to move near or over portions of southeastern
Newfoundland late Friday and Friday night as it undergoes transition
to a hurricane-force post-tropical cyclone. There is an increasing
risk of impacts from high winds, rainfall, and storm surge in
portions of Newfoundland, and interests there should monitor updates
to the forecast. 


FORECAST POSITIONS AND MAX WINDS

INIT  09/0300Z 29.7N  60.3W   85 KT 100 MPH
 12H  09/1200Z 31.5N  61.5W   85 KT 100 MPH
 24H  10/0000Z 34.9N  62.3W   85 KT 100 MPH
 36H  10/1200Z 39.3N  60.8W   80 KT  90 MPH
 48H  11/0000Z 45.2N  55.8W   75 KT  85 MPH
 60H  11/1200Z 51.6N  48.2W   70 KT  80 MPH...POST-TROP/EXTRATROP
 72H  12/0000Z 57.4N  41.6W   65 KT  75 MPH...POST-TROP/EXTRATROP
 96H  13/0000Z 63.8N  35.6W   55 KT  65 MPH...POST-TROP/EXTRATROP
120H  14/0000Z...DISSIPATED

$$
Forecaster Papin
  • Like 1
Link to comment
Share on other sites

On 9/8/2021 at 3:47 PM, OSUmetstud said:

I usually do most of my weather stuff on twitter nowadays but I'll provide some updates. 

The bifurcation between the gfs emcwf and gdps and their ensembles compared to the hmon hwrf and coamps is interesting. Hurricane models are near or just east of the avalon whereas the globals track over placentia bay/western avalon Peninsula. Makes a huge difference re: wind damage. 

This is not Igor. Igor was basically fully et/post tropical. It had been embedded with a 500mb trough in excess of 12 h...so much so that even though it made landfall in Cape Race it produce hurricane force winds all the way back northwest to Bonavista. Strong winds with Larry will be mostly found east and south of track. Also, rainfall doesn't appear to be a big deal with this one which was really Igor's most damaging element. The stationary front is well to to west over the Maritimes and not in east central Newfoundland like it was with Igor. 

If Larry does take the western avalon/placentia Bay track than the wind damage could be worse for stj and the avalon than it was for Igor. 

 

Thanks for the local perspective, Nick @OSUmetstud!  Appreciate it very much.  What's your Twitter handle?  Mine is @yconsor.  I've also been posting some updates on potential Newfoundland impacts from Larry there.

Link to comment
Share on other sites



Are those your tweets? I've interacted with your tweets a few times over the years. "yconsor", "jconsor", I suppose that didn't require much detective work there. lol..

At any rate, Larry is looking better on satellite today, even improved in a way that an eyewall may be rebuilding. Recon should be interesting. If a strong eyewall exists, those 100+ kt 850 hPa winds may start mixing down better.

Additionally, Larry still has several days to traverse sufficiently warm SSTs for reintensification given that it will be moving at a quicker pace. Shallow OHC, even at 27°C will support sufficient lapse rates in a large hurricane if it is moving fast enough and has adequate baroclinic support, which it looks like Larry will be given excellent support. Think Lorenzo in 2019. It was large and yet with excellent atmospheric dynamics pulled off Cat 5 intensity with shallow ~27°C SSTs. Larry has a larger/broader circulation than Lorenzo however, so I do not think it could pull off high end intensity of Category 4, but it certainly could tighten the gradient enough to regain major hurricane status.
9314987eab3f14f6804f4fcdf4199a0a.gif
  • Like 2
Link to comment
Share on other sites

24 minutes ago, Windspeed said:

 


Are those your tweets? I've interacted with your tweets a few times over the years. "yconsor", "jconsor", I suppose that didn't require much detective work there. lol..

At any rate, Larry is looking better on satellite today, even improved in a way that an eyewall may be rebuilding. Recon should be interesting. If a strong eyewall exists, those 100+ kt 850 hPa winds may start mixing down better.

Additionally, Larry still has several days to traverse sufficiently warm SSTs for reintensification given that it will be moving at a quicker pace. Shallow OHC, even at 27°C will support sufficient lapse rates in a large hurricane if it is moving fast enough and has adequate baroclinic support, which it looks like Larry will be given excellent support. Think Lorenzo in 2019. It was large and yet with excellent atmospheric dynamics pulled off Cat 5 intensity with shallow ~27°C SSTs. Larry has a larger/broader circulation than Lorenzo however, so I do not think it could pull off high end intensity of Category 4, but it certainly could tighten the gradient enough to regain major hurricane status.
9314987eab3f14f6804f4fcdf4199a0a.gif

 

Seems typically with a large, tilted, fast moving system you tend to see more wind field expansion than an increase in max winds. But I suppose possible the eyewall could reorganize somewhat

  • Like 3
Link to comment
Share on other sites

Seems typically with a large, tilted, fast moving system you tend to see more wind field expansion than an increase in max winds. But I suppose possible the eyewall could reorganize somewhat
Agreed. My post is intended to give a ceiling for any potential reintensification. It would still be tough for Larry to regain major hurricane status given its broad windfield. Most likely it may just become more efficient at mixing down winds to remain a hurricane. Perhaps regain Category 2 intensity at best. Current maximum winds on the 11AM AST advisory is 90 mph sustained.
  • Like 1
Link to comment
Share on other sites

15 minutes ago, Windspeed said:
40 minutes ago, olafminesaw said:
Seems typically with a large, tilted, fast moving system you tend to see more wind field expansion than an increase in max winds. But I suppose possible the eyewall could reorganize somewhat

Agreed. My post is intended to give a ceiling for any potential reintensification. It would still be tough for Larry to regain major hurricane status given its broad windfield. Most likely it may just become more efficient at mixing down winds to remain a hurricane. Perhaps regain Category 2 intensity at best. Current maximum winds on the 11AM AST advisory is 90 mph sustained.

Yeah I'm a little annoyed as this idea that it's weakening from the NHC. I think it was overestimated yesterday based on SFMR and lack of convection. So this morning's data is more indicative of its real intensity. It may have actually been weaker yesterday. The pressure fell 2mb in 95 minutes between passes and the microwave looked nice this morning.

 

20210909.1132.f17.composite.12L.LARRY.85kts.968mb.31.3N.61.5W.060pc.jpg

  • Like 5
Link to comment
Share on other sites

@OSUmetstudI agree with the idea that Larry was most likely overestimated yesterday, considering the SFMR winds and dropsondes from recon.  Larry likely got down to cat 1 at some point late yesterday into early today.  IMHO there is a good chance it will become better organized and likely will be a cat 2 until just before Newfoundland landfall.  See short thread below.
 

 

Link to comment
Share on other sites

Larry has gained significant speed in forward motion. The core has moved over the cool Labrador Current, however, interaction with the strong mid-to-upper trough, baroclinic forcing and cooler upper tropospheric temperatures are allowing convection to persist. Larry may not weaken below hurricane intensity prior to landfall. Really, the core doesn't look that bad at all given extra-tropical transition has begun.
261c5554550157f36b4352ff0d0c2a5d.gif

  • Like 1
Link to comment
Share on other sites

16 minutes ago, Windspeed said:

Larry has gained significant speed in forward motion. The core has moved over the cool Labrador Current, however, interaction with the strong mid-to-upper trough, baroclinic forcing and cooler upper tropospheric temperatures are allowing convection to persist. Larry may not weaken below hurricane intensity prior to landfall. Really, the core doesn't look that bad at all given extra-tropical transition has begun.
261c5554550157f36b4352ff0d0c2a5d.gif

That’s pretty nice organization for that latitude. This was a good long tracker. Hopefully the folks over there do alright damage wise in this storm.

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...