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Re: June 2017: ALT PTC #3 / Gulf Of Mexico Threat

Posted: Tue Jun 20, 2017 9:36 am
by DoctorMu
srainhoutx wrote:
jasons wrote:If the center gets tugged under the convection it's gonna be a shift to the east. Will have to watch satellite very closely today.
While it is possible, these sheared broad monsoonal gyres with an elongated broad surface circulation are typically influenced by the low level flow versus a vertically stacked Tropical Cyclone. The Bermuda Ridge is influencing the generally Easterly flow at the surface. It appears to me in the 24 frame visible GOES 16 imagery the general motion is to the NW and possibly WNW of the elongated low. Shear would probably need to collapse for this mess to organize under the deeper convection to the N and E.
Yes - the trough is gone and now the mid to upper level stack is SW of the surface circulation...so if anything, if the storm gets its act together it would move even farther west. I actually expect the center to move W for awhile today, even WSW. We'll see.

Re: June 2017: ALT PTC #3 / Gulf Of Mexico Threat

Posted: Tue Jun 20, 2017 9:37 am
by srainhoutx
Tropical Storm Watch extended West to San Luis Pass in Galveston County. Brazoria County not included... as of now.

BULLETIN
Potential Tropical Cyclone Three Advisory Number 4
NWS National Hurricane Center Miami FL AL032017
1000 AM CDT Tue Jun 20 2017

...TROPICAL STORM WARNING EXTENDED WESTWARD AND TROPICAL STORM WATCH
ISSUED FOR THE UPPER TEXAS COAST...
...HEAVY RAINFALL ALONG MUCH OF THE GULF COAST REMAINS THE BIGGEST
THREAT...


SUMMARY OF 1000 AM CDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...25.9N 90.5W
ABOUT 265 MI...430 KM S OF MORGAN CITY LOUISIANA
ABOUT 355 MI...565 KM SE OF GALVESTON TEXAS
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...999 MB...29.50 INCHES


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

The Tropical Storm Warning has been extended westward to High
Island, Texas.

A Tropical Storm Watch is in effect from west of High Island to San
Luis Pass, Texas.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
* High Island to the Mouth of the Pearl River

A Tropical Storm Watch is in effect for...
* West of High Island to San Luis Pass

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area, in this case within the
next 24 to 36 hours.

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

Interests elsewhere along the U.S. Gulf Coast from the central Texas
coast to the western Florida Panhandle should monitor the progress
of this system.

For storm information specific to your area, including possible
inland watches and warnings, please monitor products issued by your
local National Weather Service forecast office.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 1000 AM CDT (1500 UTC), the disturbance was centered near
latitude 25.9 North, longitude 90.5 West. The system is moving
toward the northwest near 10 mph (17 km/h) and this motion is
expected to continue through Wednesday night. A turn toward the
north-northwest is forecast early Thursday. On the forecast track,
the disturbance is expected to be near the southwest Louisiana coast
late Wednesday or Wednesday night, and move inland over western
Louisiana and eastern Texas on Thursday.

Maximum sustained winds are near 40 mph (65 km/h) with higher gusts.
Some slight strengthening is possible before the system reaches the
coast.

Satellite imagery shows that the center of the disturbance is
gradually become better defined, and it is likely that the system
will become a tropical or subtropical cyclone later today.
* Formation chance through 48 hours...high...90 percent
* Formation chance through 5 days...high...90 percent

Tropical-storm-force winds extend outward up to 205 miles (335 km),
mainly to the north and east of the center.

The estimated minimum central pressure based on buoy data is 999 mb
(29.50 inches).


HAZARDS AFFECTING LAND
----------------------
WIND: Tropical storm conditions are expected to first reach the
coast within the warning area later today and spread westward
within the warning area through Wednesday. Tropical storm
conditions are possible in the watch area on Wednesday.

RAINFALL: The disturbance is expected to produce total rain
accumulations of 6 to 9 inches with isolated maximum amounts of
12 inches over southeastern Louisiana, southern Mississippi,
southern Alabama, and the Florida Panhandle through Thursday.
Rainfall amounts of 3 to 5 inches with isolated maximum
amounts of 6 inches can be expected farther west across southwest
Louisiana into southeast Texas through Thursday.

STORM SURGE: Inundation of 1 to 3 feet above ground level
is possible along the coast in portions of the Tropical Storm
Warning area.

TORNADOES: A tornado or two is possible this afternoon and tonight
from south-central Louisiana to the western Florida Panhandle.


NEXT ADVISORY
-------------
Next intermediate advisory at 100 PM CDT.
Next complete advisory at 400 PM CDT.

$$
Forecaster Brennan

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 9:41 am
by DoctorMu
The shear is there, but is lifting NE into Louisiana. The one thing Euro, CMC, and GFS have in common is a SNS track to almost west for nearly a day...it may get underneath the shear and get better organized in the next 36 hours.

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 9:49 am
by jasons2k
Yes, I had a momentary lapse when I looked at the first visibles. Forgot to step back and look at the big picture. It's doing what it's supposed to...carry on :-)

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 9:50 am
by tireman4
The Euro was onto something..like the NAM, UKMET and CMC?

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 9:53 am
by srainhoutx
Full Package Discussion:

Potential Tropical Cyclone Three Discussion Number 4
NWS National Hurricane Center Miami FL AL032017
1000 AM CDT Tue Jun 20 2017

Visible satellite imagery and surface observations indicate that the
circulation of the low has become better organized since yesterday,
but still lacks a well-defined center. The central pressure appears
to have fallen to around 999 mb based on observations from NOAA buoy
42001, and some deep convection has begun developing a little closer
to the low's circulation center. For now the system is being
maintained as a potential tropical cyclone, however, the system
could be classified as a tropical or subtropical cyclone later
today.

The current intensity is maintained at 35 kt based largely on
continuity pending an Air Force Reserve Hurricane Hunter mission
into the system later this morning. Only limited strengthening is
forecast before the system moves inland due to the strong vertical
shear over the cyclone caused by an upper-level low centered off
the Texas coast. The new NHC intensity forecast is similar to the
previous one and is close to the intensity consensus aid.

The initial motion estimate is a somewhat uncertain 320/09 as the
there are still multiple low-level cloud swirls circulating around a
mean center, and some erratic motion is still possible until a
better-defined center forms. However, the system should be steered
generally northwestward over the next 36 hours or so as it interacts
with the aforementioned upper-level low and then turns more
north-northwestward by 48 hours as the system begins to recurve
around the mid-level ridge to the east. The NHC track forecast is a
little faster than the previous one in the short range, and shows
the system moving inland over western Louisiana and eastern Texas by
48 hours. After that time, the system should recurve into the
mid-latitude flow and accelerate northward and northeastward across
the lower Mississippi Valley and into the southern and central
Appalachians on days 3 and 4 before dissipating.

The primary hazard from this disturbance is expected to be heavy
rainfall over portions of the central and eastern Gulf Coast.
Given the nature of the circulation and the fact that wind and rain
hazards extend well north and east of the center, users are
encouraged not to focus on the details of the track forecast.


FORECAST POSITIONS AND MAX WINDS

INIT 20/1500Z 25.9N 90.5W 35 KT 40 MPH...POTENTIAL TROP CYCLONE
12H 21/0000Z 26.7N 91.6W 40 KT 45 MPH...TROPICAL CYCLONE
24H 21/1200Z 27.4N 92.6W 40 KT 45 MPH
36H 22/0000Z 28.6N 93.6W 40 KT 45 MPH
48H 22/1200Z 30.1N 94.0W 35 KT 40 MPH...INLAND
72H 23/1200Z 34.0N 92.5W 25 KT 30 MPH...INLAND
96H 24/1200Z 37.5N 84.0W 20 KT 25 MPH...POST-TROP/INLAND
120H 25/1200Z...DISSIPATED

$$
Forecaster Brennan

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 10:00 am
by srainhoutx
Update from Jeff...he is busy in meetings as you can expect...

At 1000am a tropical storm Watch is issued for the upper TX coast from High Island, TX to San Luis Pass, TX including Galveston Bay/County, Harris County, Liberty County and Chambers County.

At 1000am a tropical storm warning is extended westward from Intracoastal City, LA to High Island TX.

There has been no significant change in the forecast track reasoning nor impacts for SE TX at this time.

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 10:52 am
by davidiowx
Looking at WV, it looks like that ULL is really trying to get out of the way towards the SW rather quickly.

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 10:52 am
by jasons2k
Just my $.02 cents. I think this pre-TC system is just causing confusion. Just call it TD3 and carry on already.

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 11:00 am
by srainhoutx
jasons wrote:Just my $.02 cents. I think this pre-TC system is just causing confusion. Just call it TD3 and carry on already.
Two years ago at Conference, Doc Neil and I questioned the reasoning for the changes coming. This year we just shook our heads sitting at our table in the back of Conference Room knowing that this would cause confusion. It's up to we weather savoy folks to "educate" those not so weather savoy of these new Products. While the idea of Watches/Warnings have long been discussed prior to an actual storm forming...think Humberto 2007...fortunately this is a "test year" before implementation next Season. Share your views with the NHC. They need to hear exactly why you think this is confusing... ;)

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 11:07 am
by StormOne
GFS ain't budging, still showing the Sabine River track with 999mb at landfall. Completely drenches the Louisiana coast.

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 11:25 am
by davidiowx
Tropics Watch just posted this video:
https://twitter.com/TropicsWatch/status ... 5082658817

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 11:29 am
by TexasBreeze
Most of the area gets 2 + inches of rain from the 12z GFS run.

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 11:31 am
by ticka1
When is recon flying

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 11:31 am
by jasons2k
They should just get past the bureaucratic barriers, stick with the existing classification system and issue advisories with Invests. Simple.

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 11:35 am
by tireman4
ticka1 wrote:When is recon flying
They are in there now. They have been for, I think, a couple of hours.

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 11:40 am
by Cromagnum
Now it's official.

https://youtu.be/Fq9a47CpFz0

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 12:00 pm
by ticka1
Is it a TD yet?

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 12:03 pm
by tireman4
Well, it has not been declared one....not sure what the pro mets are thinking...the winds would dictate such, I will say that. This is just an amateur speaking. There is more criteria than just winds....

Re: June 2017: ALT PTC #3 / Tropical Storm Watch Issued

Posted: Tue Jun 20, 2017 12:15 pm
by Portastorm
I realize looks can be deceiving when viewing satellite loops on these kinds of systems, but after reviewing the 48-image GOES 16 visible satellite of the Gulf ... it doesn't look like this thing is moving right now. At all.