2018 Tropical Storm Alberto

[JayF]

I am going to go ahead and create this. For Wes, I was hoping that Invest 90L would hold off but it looks like it might actually become a named storm. And with that, I present you with a Spaghetti Model.

 

[JayF]

ZCZC MIATWOAT ALL
TTAA00 KNHC DDHHMM

Special Tropical Weather Outlook
NWS National Hurricane Center Miami FL
130 PM EDT Thu May 24 2018

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

1. A broad surface low drifting slowly northward over the eastern
Yucatan Peninsula continues to become better defined. Although
showers and thunderstorms, along with strong gusty winds, remain
primarily over the adjacent waters of the northwestern Caribbean
Sea, environmental conditions are forecast to become more conducive
for development through early next week, and a subtropical or
tropical depression is likely to form by late Saturday over the
southeastern Gulf of Mexico. An Air Force Reserve reconnaissance
aircraft is scheduled to investigate the disturbance Friday
afternoon, if necessary. Locally heavy rainfall is forecast across
western Cuba and over much of Florida and the northern Gulf Coast
into early next week. In addition, the threat of rip currents will
steadily increase along the Gulf coast from Florida westward to
Louisiana over the Memorial Day weekend. For more information on
these threats, please see products issued by your local weather
office. The next Special Tropical Weather Outlook on this system
will be issued by 800 PM EDT this evening.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 5 days...high...90 percent.

Forecaster Stewart

 

[Blountwolf]

Per visible, A little bit of a spin already around Cozumel.

 

[Kory]

Pretty good consensus for landfall on the Mississippi/Alabama coasts. Euro is a solid category 1 hurricane. Trough orientation helps with outflow as it approaches and slows down along the Gulf Coast. Below are forecast 10m wind gusts...pretty impressive.

 

[Daryl]

Special Tropical Weather Outlook
NWS National Hurricane Center Miami FL
730 AM EDT Fri May 25 2018

Satellite images and surface observations indicate that the low
pressure system located over the northwestern Caribbean Sea just
east of the Yucatan Peninsula of Mexico has become better defined
overnight, and thunderstorm activity has also increased and become
better organized. Environmental conditions are forecast to steadily
become more conducive for development, and a subtropical or tropical
depression or storm is likely to form by Saturday over the
northwestern Caribbean Sea or the southeastern Gulf of Mexico. An
Air Force Reserve reconnaissance aircraft is scheduled to
investigate the low this afternoon.
Locally heavy rainfall is forecast across western Cuba and over much
of Florida and the northern Gulf Coast into early next week. This
system could also bring tropical-storm-force winds and storm surge
to portions of the northern Gulf Coast by late this weekend or early
next week. In addition, the threat of rip currents will steadily
increase along the Gulf Coast from Florida westward to Louisiana
over the Memorial Day weekend.
* Formation chance through 48 hours...high...90 percent.
* Formation chance through 5 days...high...90 percent.

 

[JayF]

Most of the models have this becoming a tropical storm. I wouldn't say though that a Cat 1 is out of the question. Its going to be a busy couple of days in the weather forecasting offices around the coast.

 

[Kory]

Recon is headed down there this afternoon. Overall, there are a few circulations rotating around the main circulation which is mostly exposed. I can't imagine they upgrade it just yet...

 

[JayF]

Recon is headed down there this afternoon. Overall, there are a few circulations rotating around the main circulation which is mostly exposed. I can't imagine they upgrade it just yet...

If it continues to Strengthen. I see it becoming Alberto at the next update.

 

[Kory]

 

[JayF]

Current Goes-16 (Goes-East) image of Invest 90L

 

[Kory]

We have Subtropical Storm Alberto. Feel free to update the thread title.

 

[JayF]

00
WTNT41 KNHC 251444
TCDAT1

Subtropical Storm Alberto Discussion Number 1
NWS National Hurricane Center Miami FL AL012018
1000 AM CDT Fri May 25 2018

The broad low pressure system that the NHC has been tracking for
the past several days over the Yucatan Peninsula has finally moved
offshore over the waters of the northwestern Caribbean Sea.
Although the system possesses multiple low-level circulations, the
overall larger circulation has improved since yesterday. Given that
the system has been interacting with a sharp upper-level trough,
the strongly sheared low has been designated a subtropical storm.
The initial intensity is based on buoy and ship observations of
30-35 kt. Ship 3ETA7 located just northeast of the center at 1100Z
reported 45-kt winds at 50 meters elevation. Those winds equate to
35-40 kt at 10 meters elevation. An Air Force Reserve Hurricane
Hunter Aircraft is scheduled to investigate Alberto later this
afternoon and provide more information on the storm's structure and
intensity.

The initial motion estimate is an uncertain 020/05 kt. The broad
inner-core wind field and multiple swirls makes the short-term
motion forecast a little tricky. However, a large subtropical ridge
to the east should generally induce a slow north to north-
northeastward motion for the next 24 hours or so. After that, the
ridge across the western Atlantic and Florida, along with a
mid/upper-level low forecast to develop over the central Gulf of
Mexico, should result in a faster northward motion at 36-48 hours,
followed by a gradual turn toward the northwest around the
northern fringe of the aforementioned mid/upper-level low. By 96
hours, the cyclone is forecast to slow down significantly as it
nears the north-central Gulf Coast due to a large weakness in the
subtropical ridge forecast to develop over the Deep South. The
official forecast track closely follows the consensus models TVCN
and HCCA.

Given the broad inner-core wind field and belligerent westerly wind
shear forecast to persist for the next 48 hours or so, only gradual
intensification is expected. By 72 hours, however, when the cyclone
is forecast to move slowly over above-normal SSTs of 28-29C and into
an upper-level col and weak wind shear, some additional
strengthening could occur. For now, the intensity forecast will
remain conservative due to possible intrusion of dry mid-level air
before landfall, and closely follows the HCCA consensus model.

KEY MESSAGES:

1. Regardless of its exact track and intensity, Alberto is expected
to produce heavy rainfall and flash flooding over the northeastern
Yucatan Peninsula of Mexico, western Cuba, southern Florida and the
Florida Keys. Rainfall and flooding potential will increase across
the central Gulf Coast region and the southeastern United States
later this weekend and early next week when Alberto is expected to
slow down after it moves inland.

2. Alberto could bring tropical storm conditions and storm surge to
portions of the central and eastern Gulf Coast later this weekend
and early next week, although it is too soon to specify the exact
location and magnitude of these impacts. Residents in these areas
should monitor the progress of Alberto, as tropical storm and storm
surge watches may be required later today or tonight.

3. Dangerous surf and rip current conditions are affecting portions
of the Yucatan Peninsula and western Cuba and will likely spread
along the eastern and central U.S. Gulf Coast later this weekend.

FORECAST POSITIONS AND MAX WINDS

INIT 25/1500Z 19.7N 86.8W 35 KT 40 MPH
12H 26/0000Z 20.5N 86.6W 35 KT 40 MPH
24H 26/1200Z 22.0N 86.2W 40 KT 45 MPH
36H 27/0000Z 24.1N 85.8W 45 KT 50 MPH
48H 27/1200Z 26.7N 86.1W 50 KT 60 MPH
72H 28/1200Z 29.3N 87.9W 55 KT 65 MPH
96H 29/1200Z 31.0N 89.1W 30 KT 35 MPH...INLAND
120H 30/1200Z 33.6N 88.7W 20 KT 25 MPH...INLAND

$$
Forecaster Stewart

 

[JayF]

 

[Taylor Campbell]

This could end up being quite the tornado producer.

 

[WesL]

Good morning from my new hurricane hunting vessel aka Carnival Fantasy. Partly cloudy skies as we are traversing the Gulf of Mexico at the moment. No word from the crew if we are still expected to arrive in Cozumel tomorrow. I’m
Betting we divert to Costa Maya on the western side of the of the Yucatan. I’m making full use of the ships facilities to prepare for Alberto’s arrival. More to come soon.

 

[rolltide_130]

That current track is trouble for NOLA. That's the classic track to funnel water right up into the metro, even if its not a particularly strong system. Could be a significant flooding risk there even if storm surge is relatively weak.

 

[Taylor Campbell]

This could end up being quite the tornado producer.

I just saw something on the EURO that was pretty crazy in regards to this potential threat.

 

[Kory]

That current track is trouble for NOLA. That's the classic track to funnel water right up into the metro, even if its not a particularly strong system. Could be a significant flooding risk there even if storm surge is relatively weak.

The latest NAM is a very odd angle of approach that I think has only been done by the big 1947 hurricane. That wrecked a lot of the city of New Orleans.

Surge and rainfall will be a big problem with this system as it slows and meander a while along the Northern Gulf Coast.

 

[apocalyptic_pleasures]

This could end up being quite the tornado producer.

Would the proximity to the Upper Low help enhance the tornado threat?

 

[akt1985]

If Alberto becomes a hurricane before landfall, would this be the first hurricane in the Atlantic Basin in the month of May?