Jump to content
  • Member Statistics

    17,606
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

Major Hurricane Larry


WxWatcher007
 Share

Recommended Posts

The strongest signal of the season so far on guidance for TC genesis and intensification has been for newly designated Invest 90L. Expected to curve but long way out. Discuss. 
 

0DLb4St.png
 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Mon Aug 30 2021

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center is issuing advisories on Tropical  
Storm Ida, located inland over western Mississippi, and on recently 
upgraded Tropical Storm Kate, located over the central tropical 
Atlantic.

1. Satellite-derived wind data and satellite imagery indicate that an 
area of low pressure has formed over the far eastern Tropical 
Atlantic in association with a tropical wave that recently moved off 
the west coast of Africa.  Environmental conditions are conducive 
for development, and a tropical depression is likely to form within 
the next couple of days while the system moves west-northwestward at 
10 to 15 mph over the eastern tropical Atlantic. 
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 5 days...high...90 percent.

 

  • Like 2
Link to comment
Share on other sites

With regards to land interaction, it is worth noting that the ECMWF has been trending further south in track guidance now into the medium range. This is why I would not immediately discount the system as only an ACE producer. Though it does remind me of 2020 Hurricane Teddy in its infancy stage (as far as recent CV-long trackers go), and certainly a close call with Bermuda comes to mind, or perhaps even a potential post-tropical interaction with far eastern Canada. At any rate, the pattern is still far enough downstream that it could evolve into a surprise here. The system could get left behind in the central Atlantic/MDR and we're still early enough in the year that pesky WATL 500 hPa dam could rebuild.d736b67933e327fe7f0d992aba7783e5.gif

  • Like 1
Link to comment
Share on other sites

1 hour ago, Windspeed said:

With regards to land interaction, it is worth noting that the ECMWF has been trending further south in track guidance now into the medium range. This is why I would not immediately discount the system as only an ACE producer. Though it does remind me of 2020 Hurricane Teddy in its infancy stage (as far as recent CV-long trackers go), and certainly a close call with Bermuda comes to mind, or perhaps even a potential post-tropical interaction with far eastern Canada. At any rate, the pattern is still far enough downstream that it could evolve into a surprise here. The system could get left behind in the central Atlantic/MDR and we're still early enough in the year that pesky WATL 500 hPa dam could rebuild.d736b67933e327fe7f0d992aba7783e5.gif

Imo there's like a 95% it just runs up ACE but GFS has also been trending further south and west so am not 100% sold 

gfs_mslp_wind_eatl_fh186_trend.gif

Link to comment
Share on other sites

The intensity forecast is pretty aggressive for an initial advisory by the NHC. 80 kts by three days. 90 kts in five days. Likely due to the overwhelming intensification trends by the globals and ensemble clusters. Good chance Larry will be the next major hurricane barring some complete failure to structurally organize, and even with slow organization, it probably reaches major intensity beyond five days anyway.
f6d611c7c3bcdbe6df4e78dff781842e.jpg

Link to comment
Share on other sites

Good morning Larry 

BULLETIN
Tropical Storm Larry Advisory Number   3
NWS National Hurricane Center Miami FL       AL122021
800 AM CVT Wed Sep 01 2021

...DEPRESSION STRENGTHENS INTO TROPICAL STORM LARRY OVER THE
EASTERN TROPICAL ATLANTIC...


SUMMARY OF 800 AM CVT...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...12.3N 24.8W
ABOUT 175 MI...280 KM S OF THE SOUTHERNMOST CABO VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H
PRESENT MOVEMENT...W OR 280 DEGREES AT 20 MPH...31 KM/H
MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND OUTLOOK
----------------------
At 800 AM CVT (0900 UTC), the center of Tropical Storm Larry was
located near latitude 12.3 North, longitude 24.8 West. Larry is
moving toward the west near 20 mph (31 km/h).  A westward to 
west-northwestward motion is expected during the next couple of 
days, followed by a turn to the northwest over the weekend.

Maximum sustained winds have increased to near 45 mph (75 km/h) 
with higher gusts. Additional strengthening is forecast during the 
next few days and Larry is forecast to become a hurricane by late 
Thursday or Friday.

Tropical-storm-force winds extend outward up to 60 miles (95 km)
from the center.

The estimated minimum central pressure is 1003 mb (29.62 inches).
Link to comment
Share on other sites

Major in 3 days

Tropical Storm Larry Discussion Number   3
NWS National Hurricane Center Miami FL       AL122021
800 AM CVT Wed Sep 01 2021

Deep convection with cloud tops colder than -80C have increased over 
and to the west of the low-level center since the previous advisory. 
Subjective satellite intensity estimates at 0600 UTC from TAFB and 
SAB were T2.5/35 kt and T3.0/45 kt, while the most recent objective 
intensity estimates from UW-CIMSS are T2.8/41 kt from ADT and 37 kt 
from SATCON. An average of these intensity estimates support 
increasing the advisory intensity to 40 kt, making the cyclone 
Tropical Storm Larry. In addition, 0300 UTC and 0700 UTC 
observations from ship VRNF3, which recently passed through the 
center of Larry, reported a pressure of 1006.8 mb and winds near 25 
kt. These data were the basis for the estimated central pressure of 
1003 mb, a pressure value that also supports an intensity of 40 kt.

Larry has turned more westward over the past several hours, and the 
new motion estimate is 280/17 kt. Larry is expected to move around 
the southern and southwestern periphery of the sprawling 
Bermuda-Azores ridge for the next 5 days, resulting in a general 
west motion for the next 36 hours or so, followed by a turn toward 
the west-northwest on Friday, and a northwestward motion over the 
weekend and continuing into early next week. There has been a 
pronounced westward shift in the track guidance for this cycle, with 
the greatest shift coming from the GFS model. Over the past 36 
hours, the GFS has shifted its track westward by more than 500 nmi, 
and even the latest shift still keeps the GFS model the easternmost 
track forecast in the guidance suite. In contrast, the ECMWF and 
UKMET models, which lie along the westernmost portion of the 
guidance envelope, have been fairly stable. Owing to the westward 
shift in the overall guidance envelope, and considering the GFS 
solution as an outlier model, the new NHC forecast track has also 
been shifted westward, and lies between the NOAA-HCCA 
corrected-consensus model to the south, and the tightly packed TVCA 
simple-consensus model and FSSE corrected-consensus model to the 
north. Given the poor handling of the ridge to the north of Larry by 
the GFS, subsequent NHC forecast tracks may have to be shifted 
farther west.

Given the improved inner-core wind field based on earlier ASCAT wind 
data and reports from ship VRNF3, along with warm sea-surface 
temperatures of 28 deg C and light easterly to southeasterly 
vertical shear of around 5 kt, steady strengthening is expected for 
the next 24 hours or so. By 36 hours when Larry is expected to be a 
hurricane and have a well-established and tighter inner-core wind 
field and possibly an eye, rapid intensification is forecast, with 
Larry becoming a major hurricane by 72 hour. This in large part due 
to the massive equatorward upper-level outflow pattern that all 
of the global and regional models are forecasting, which is the 
same type of outflow pattern that recently occurred with Hurricane 
Ida. The new official intensity forecast is above the previous 
advisory forecast by about 10 kt at all forecast times, and 
conservatively follows an average of the Decay-SHIPS, COAMPS-TC, 
FSSE, and ECMWF models. This intensity forecast is near the upper 
end of the guidance envelope and is above the other consensus 
intensity models.


FORECAST POSITIONS AND MAX WINDS

INIT  01/0900Z 12.3N  24.8W   40 KT  45 MPH
 12H  01/1800Z 12.5N  27.5W   50 KT  60 MPH
 24H  02/0600Z 12.6N  30.6W   60 KT  70 MPH
 36H  02/1800Z 13.1N  33.7W   70 KT  80 MPH
 48H  03/0600Z 13.6N  36.8W   85 KT 100 MPH
 60H  03/1800Z 14.4N  39.7W   95 KT 110 MPH
 72H  04/0600Z 15.5N  42.0W  100 KT 115 MPH
 96H  05/0600Z 18.2N  46.9W  105 KT 120 MPH
120H  06/0600Z 21.3N  50.6W  105 KT 120 MPH

$$
Link to comment
Share on other sites

Even though the cyclone is in its infancy, the circulation is quite large. I'd imagine Larry is going to be a large hurricane as has been hinted by modeling. A core has not developed yet but there are good banding features already in progress. Probably won't take long to form a core once deep convection becomes centralized.
3c57710a8f6d980c53a01aced0f13a5d.gif

  • Like 1
Link to comment
Share on other sites

Larry is far enough south in track right now on a westward heading that it doesn't appear thermodynamics are going to be much of an issue at its given rate of motion. It is currently moving over 27-28°C SSTs, and will be crossing over a region of 28°C SSTs soon. It has a fairly moist envelope. It also looks like the vigorous mid-level circulation is wrapping convection up pretty fast here. Larry looks to be steadily strengthening and may be a hurricane sooner than forecast. It might even pull off a large eye right out the gate. The last CV hurricanes I can remember forming a large stable eye early into hurricane intensity were Isabel and Igor.76806039e68c459473d6c74937e8749b.gif

  • Like 2
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...