Jump to content
  • Member Statistics

    16,790
    Total Members
    7,904
    Most Online
    Dranger
    Newest Member
    Dranger
    Joined

Major Hurricane Delta


hlcater
 Share

Recommended Posts

About time for this one. Models are already fairly robust with 92L with the majority reaching hurricane strength and a good chunk with major status. Environment through D4 is just about as good as it gets, so the intensity ceiling is probably quite high on this one relatively speaking. Cool water, shear and dry air should ensure weakening by landfall at least.

  • Like 1
Link to comment
Share on other sites

If this system does become a hurricane and threaten the US gulf coast, the water over the northern gulf is no longer the fuel it was when Sally traversed the area.

The image is from Ryan Maue on Twitter.

Ejb-9jlXkAAepy3?format=png%26name=medium&key=2896d958c6428c8d0b046581a33d24f6853d44697d3f6e477a7f6bbb6ac5d7dc

2018 October, this year is not. Been a number of frontal boundaries and several TCs already in the N. GOM to kill shallow heat content. But as GOL pointed out, SW FL is still very much in play for a major through the remainder of the month. 92L likely won't be the last W. Caribbean system during the next three weeks.
  • Like 1
Link to comment
Share on other sites

Convection is flaring up nicely over the center. This seems ahead of schedule for TCG. Parameters are favorable for significant intensification by the time this reaches the straits. Could very well be an overperformer, perhaps even a major by the time it reaches the central GOM. Then significant weakening into landfall. If it becomes a large hurricane, significant surge will be the story here.

  • Like 2
Link to comment
Share on other sites

GFS gets down to 978mb in the central gulf,     but the northern gulf shear wall kicks in full force this run. Looks like 40-50 knots as it's making landfall in SE LA. Going to get shredded.  

 

Actually hoping for a similar scenario. Just make it a Cat5 in the southern gulf then weaken it back to a TS before landfall.

  • Like 1
Link to comment
Share on other sites

GFS gets down to 978mb in the central gulf,     but the northern gulf shear wall kicks in full force this run. Looks like 40-50 knots as it's making landfall in SE LA. Going to get shredded.  
 
Actually hoping for a similar scenario. Just make it a Cat5 in the southern gulf then weaken it back to a TS before landfall.
That's not far off from a hypothetical unfolding. It could reach Cat 4 and then weaken rapidly prior to landfall.
Link to comment
Share on other sites

52 minutes ago, Windspeed said:
1 hour ago, Amped said:
GFS gets down to 978mb in the central gulf,     but the northern gulf shear wall kicks in full force this run. Looks like 40-50 knots as it's making landfall in SE LA. Going to get shredded.  
 
Actually hoping for a similar scenario. Just make it a Cat5 in the southern gulf then weaken it back to a TS before landfall.

That's not far off from a hypothetical unfolding. It could reach Cat 4 and then weaken rapidly prior to landfall.

Ha...opposite of everything else this year, lol

Link to comment
Share on other sites

Tropical Depression Twenty-Six Discussion Number   2
NWS National Hurricane Center Miami FL       AL262020
1100 PM EDT Sun Oct 04 2020

Satellite data indicate that the disturbance just south of Jamaica 
has become better organized this evening.  Microwave and shortwave 
infrared images indicate that the center is now well defined, and 
deep convection has been persisting near and to the south of the 
center.  Based on this data, the system now meets the criteria to be 
considered a tropical depression.  The initial intensity remains 30 
kt for this advisory.

The depression is currently moving west-northwestward at 8 kt on the
southern side of an Atlantic subtropical ridge.  A continued
west-northwest to northwest motion at about the same forward speed
is expected during the next 24 to 36 hours, taking the system across
the Cayman Islands and toward western Cuba.  Around the time the
depression is expected to be near western Cuba, the models show it
accelerating northwestward as it moves in the faster flow between
the ridge and Tropical Storm Gamma.  This motion should bring the
tropical cyclone into the southern Gulf of Mexico Tuesday night or
early Wednesday. Later on, a notable slow down and a turn to the
north is forecast to occur late in the week when the depression will
likely be approaching the northern Gulf coast.  This change in the
forecast motion is a result of the ridge weakening and a trough
approaching the cyclone from the west.  The models are in relatively
good agreement, which is surprising since they often diverge for
weak systems, and the NHC track forecast lies near the middle of the
guidance envelope.

There is currently some northeasterly shear affecting the
depression, but the models all show the shear lessening by tomorrow
and remaining fairly light for the next few days.  These improving
upper-level wind conditions combined with a moist air mass and warm
waters should allow for at least steady strengthening during the
next few days.  By late in the week, when the storm is forecast to
approach the U.S. Gulf coast, there could be an increase in
southerly or southwesterly shear, which could limit additional
strengthening by that time.  The NHC intensity forecast lies fairly
close to the IVCN and HCCA consensus aids, and shows the depression
becoming a hurricane near western Cuba with additional strengthening
over the Gulf of Mexico.

Users are reminded that the average 4- and 5-day NHC track forecast
errors are about 160 to 200 miles at those time periods,
respectively.

Key Messages:

1. Tropical storm conditions are expected in the Cayman Islands
beginning late Monday, and a Tropical Storm Warning is in
effect.

2. Dangerous storm surge and hurricane conditions are possible in
portions of western Cuba and the Isle of Youth by Tuesday
afternoon, and a Hurricane Watch is in effect.

3. Heavy rainfall will affect portions of Hispaniola, Jamaica, the
Cayman Islands, and western Cuba during the next few days and could
lead to life-threatening flash floods and mudslides.

4. The system is forecast to approach the northern Gulf Coast late
this week as a hurricane. While there is large uncertainty in the
track and intensity forecasts at these time ranges, there is a risk
of dangerous storm surge, wind, and rainfall hazards along the coast
from Louisiana to the western Florida Panhandle. Residents in these
areas should monitor the progress of the system and check for
updates to the forecast during the week.


FORECAST POSITIONS AND MAX WINDS

INIT  05/0300Z 17.0N  77.3W   30 KT  35 MPH
 12H  05/1200Z 17.4N  78.3W   35 KT  40 MPH
 24H  06/0000Z 18.3N  79.8W   40 KT  45 MPH
 36H  06/1200Z 20.0N  81.9W   50 KT  60 MPH
 48H  07/0000Z 22.2N  84.4W   65 KT  75 MPH
 60H  07/1200Z 24.1N  87.0W   80 KT  90 MPH
 72H  08/0000Z 25.4N  88.8W   85 KT 100 MPH
 96H  09/0000Z 27.2N  90.4W   90 KT 105 MPH
120H  10/0000Z 30.0N  89.9W   75 KT  85 MPH...INLAND

$$
Forecaster Cangialosi

Link to comment
Share on other sites

GFS 978mb at 48hrs this run. Also further south giving it more time to bomb. 

Edit Bottoms out at 966hrs.

Core organized at around 30hrs  992mb probably Cat1.   Avoids land and doesn't start to hit the cooler waters in the gulf until around 66hrs.   That would give it 36hrs.

Only thing keeping the environment from being perfect  is Gamma,.   Hard to tell if Gamma decides to bail out or hang in there, it's been inconsistent from run to run.

 

 

Link to comment
Share on other sites

Here's the 8AM EDT upgrade:

000
WTNT31 KNHC 051139
TCPAT1

BULLETIN
Tropical Storm Delta Intermediate Advisory Number 3A
NWS National Hurricane Center Miami FL       AL262020
800 AM EDT Mon Oct 05 2020

...TROPICAL DEPRESSION STRENGTHENS INTO A TROPICAL STORM...
...ADDITIONAL STRENGTHENING LIKELY OVER THE NEXT FEW DAYS...


SUMMARY OF 800 AM EDT...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...16.4N 78.4W
ABOUT 130 MI...210 KM S OF NEGRIL JAMAICA
ABOUT 270 MI...440 KM SE OF GRAND CAYMAN
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 9 MPH...15 KM/H
MINIMUM CENTRAL PRESSURE...1004 MB...29.65 INCHES


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

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Hurricane Watch is in effect for...
* Cuban provinces of Pinar del Rio and Artemisa
* Isle of Youth

A Tropical Storm Warning is in effect for...
* Cayman Islands including Little Cayman and Cayman Brac

A Tropical Storm Watch is in effect for...
* Cuba province of La Habana

A Hurricane Watch means that hurricane conditions are possible
within the watch area, generally within 48 hours.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

For storm information specific to your area, please monitor
products issued by your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 800 AM EDT (1200 UTC), the center of Tropical Storm Delta was 
located near latitude 16.4 North, longitude 78.4 West. The 
storm is moving toward the west-northwest near 9 mph (15 km/h), and 
this general motion should continue for the next day or so.  A 
faster northwestward motion is expected on Tuesday and Wednesday.  
On the forecast track, the center of Delta is expected to 
move away from Jamaica later today, move near or over the Cayman 
Islands later tonight, and approach the Isle of Youth and western 
Cuba Tuesday afternoon or evening. Delta is forecast to move into 
the southeastern Gulf of Mexico Tuesday night or early Wednesday.

Maximum sustained winds have increased to near 40 mph (65 km/h) 
with higher gusts. Additional strengthening is expected during the 
next few days, and the tropical storm is expected to be a hurricane 
when it moves near or over western Cuba.

Tropical-storm-force winds extend outward up to 45 miles (75 km) 
from the center.

The estimated minimum central pressure is 1004 mb (29.65 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Tropical Storm Delta can be found in the Tropical 
Cyclone Discussion under AWIPS header MIATCDAT1, WMO header WTNT41 
KNHC, and on the web at www.hurricanes.gov/text/MIATCDAT1.shtml.

STORM SURGE:  A dangerous storm surge will raise water levels by
as much as 3 to 5 feet above normal tide levels along the immediate
coast of the Isle of Youth and along the south coast of western
Cuba near and to right of where the center makes landfall. Near the
coast, the surge will be accompanied by large and dangerous waves.

RAINFALL:  Through midweek, Delta is expected to produce 3 to
5 inches of rain with isolated maximum totals of 8 inches across
Jamaica and western Cuba. This rainfall could lead to significant
flash floods and mudslides. Over the Cayman Islands, 2 to 4 inches
of rainfall will be possible with this system.

WIND:  Tropical storm conditions are expected in the Cayman Islands
beginning late today.  Hurricane conditions are possible within
the Hurricane Watch area by Tuesday afternoon, with tropical storm
conditions possible by early Tuesday.  Tropical Storm conditions
are possible in the Tropical Storm Watch area in Cuba by early
Tuesday.


NEXT ADVISORY
-------------
Next complete advisory at 1100 AM EDT.

$$
Forecaster Brown

 

Link to comment
Share on other sites

Current NHC track mostly avoids the cold eddy in the Central Gulf and minimizes travel time over cooler water prior to any Gulf Coast landfall. Further east=weaker due to to Cuba interaction and lower SST/heat content. Delta will also be moving much faster than Sally. But the cooler shelf waters should make any landfall stronger than NHC forecast unlikely, plus it will likely be starting to weaken before landfall, even before considering any shear.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...