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Hurricane Marco


Floydbuster
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BULLETIN
Tropical Storm Marco Advisory Number  16
NWS National Hurricane Center Miami FL       AL142020
400 AM CDT Mon Aug 24 2020

...HURRICANE WARNINGS DISCONTINUED FOR MARCO BUT DANGEROUS STORM 
SURGE STILL ANTICIPATED...


SUMMARY OF 400 AM CDT...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...27.6N 88.2W
ABOUT 115 MI...190 KM SSE OF THE MOUTH OF THE MISSISSIPPI RIVER
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES


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

The Hurricane Warning from Morgan City Louisiana to the Mouth of the
Pearl River has been changed to a Tropical Storm Warning.

The Hurricane Watch for Lake Pontchartrain, Lake Maurepas, and
Metropolitan New Orleans has been discontinued.

The Tropical Storm Watches west of Intracoastal City Louisiana and
from the Mississippi/Alabama border to the Alabama/Florida
border have been discontinued.

All Storm Surge Watches have been discontinued.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for....
* Morgan City Louisiana to Ocean Springs Mississippi
* Lake Borgne

A Tropical Storm Warning is in effect for...
* Intracoastal City to the Mississippi/Alabama border
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
during the next 36 hours in the indicated locations. For a
depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov.  This is a life-threatening situation.  Persons
located within these areas should take all necessary actions to
protect life and property from rising water and the potential for
other dangerous conditions.  Promptly follow evacuation and other
instructions from local officials.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area, in this case within 12
to 24 hours.

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 OUTLOOK
----------------------
At 400 AM CDT (0900 UTC), the center of Tropical Storm Marco was
located near latitude 27.6 North, longitude 88.2 West. Marco is
moving toward the northwest near 10 mph (17 km/h).  Marco is 
forecast to approach the coast of Louisiana this afternoon, and 
then turn westward and move very close to the coast of Louisiana 
through Tuesday night.

Data from the Hurricane Hunter plane indicate that maximum
sustained winds have decreased to near 60 mph (95 km/h) with higher 
gusts. Further weakening is expected, and Marco is forecast to 
become a tropical depression late on Tuesday and dissipate on 
Wednesday.

Tropical-storm-force winds extend outward up to 105 miles (165 km), 
primarily northeast of the center.

The estimated minimum central pressure is 1003 mb (29.62 inches).

 

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Tropical Storm Marco Discussion Number  16
NWS National Hurricane Center Miami FL       AL142020
400 AM CDT Mon Aug 24 2020

Marco is clearly weakening tonight.  Data from an Air Force Reserve 
Hurricane Hunter mission showed that flight-level and SFMR had 
decreased along with a substantial rise in central pressure.  In 
addition, GOES-16 1-min satellite data show the surface center well 
displaced from the deep convection, and it appears that Marco is 
decoupling from its mid-level circulation to the northeast.  The 
initial wind speed is set to 50 kt, and that could be generous.

Some large changes have been required on this forecast. Considering 
the shear is only forecast to increase, there is no significant 
chance that Marco re-intensifies to a hurricane, and the hurricane 
warnings have been replaced with tropical storm warnings.  
Furthermore, now that the storm is losing vertical coherence, the 
intensity forecast has been decreased as well, and is fairly 
consistent with the model consensus and almost every model.

Marco has turned northwestward this morning at about 9 kt. The 
storm should gradually turn westward as it approaches southeastern 
Louisiana due to the shallower cyclone feeling the low-level ridge. 
Marco will likely dissipate in a couple of days near the 
Texas/Louisiana border due to continued strong shear.  Guidance has 
come into better agreement on the track going slightly inland or 
just brushing the Louisiana coast, and the track has been nudged 
southward on this advisory.  It should be noted that the heaviest 
rain and strongest winds will likely be northeast of the center, so 
users should not focus on the exact track of the cyclone.


Key Messages:

1. Gusty winds, dangerous storm surge, and heavy rainfall are 
expected from Marco along portions of the Gulf Coast beginning
later today. Interests in these areas should follow any advice given
by local government officials.

2. Tropical Storm Laura could bring additional storm surge, 
rainfall, and wind impacts to portions of the U.S. Gulf Coast by the 
middle of the week. This could result in a prolonged period of 
hazardous weather for areas that may also be affected by Marco. 
Interests there should monitor the progress of Marco and Laura and 
updates to the forecast during the next few days.


FORECAST POSITIONS AND MAX WINDS

INIT  24/0900Z 27.6N  88.2W   50 KT  60 MPH
 12H  24/1800Z 28.6N  89.2W   45 KT  50 MPH
 24H  25/0600Z 29.2N  90.8W   35 KT  40 MPH...INLAND
 36H  25/1800Z 29.5N  92.7W   30 KT  35 MPH...OVER WATER
 48H  26/0600Z 29.4N  94.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
 60H  26/1800Z...DISSIPATED

$$
Forecaster Blake
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Nice near term disco by MOB for my area this morning!

NEAR TERM UPDATE /Now Through Tuesday/...As of this morning, the
Tropical Storm Watch was cancelled for Mobile and Baldwin
Counties in Alabama as well as George and Stone counties in
southeast Mississippi. However, windy conditions will be possible
today. Thus, a Wind Advisory was issued through 7PM CDT this
evening for coastal Mobile and coastal Baldwin counties (mainly
along the immediate coast) for easterly winds 15-25 mph with gusts
up to 35 mph. /26

The main point is that the next 48 hours or so will be rather
wet. Marco is currently in a world of absolute hurt as 30 knots of
southwesterly shear from the upper trough over the ARKLATEX
region has begun to decouple the low level circulation from the
mid-level circulation. However as long as there is deep convection
associated with the mid-level circulation, the low-level
circulation will continue to attempt to move with the mid-level
circulation causing the track to potentially shift a little more
east than originally expected and the NHC`s latest track reflects
that (about 20 mile eastward shift given the storms position).
This really won`t have much of an impact on us as the shear will
only increase with time and the low-levels will eventually
decouple causing the low-level center to track westward and the
mid-level center to continue moving north towards our area.
Imagine the head of the storm going one way and the legs going the
opposite direction. Since the mid-level circulation is expected
to move across the area, a plume of 2 to 2.5 inches PWATs will
overspread the area tonight into Monday. Typically with these
highly sheared systems most of the rainfall ends up being well to
the east from the actual center and in this situation thats us.
Scattered to numerous storms will be expected as lift associated
with that Mid-level center increases over the area beginning along
the coast later tonight then slowly spreading inland throughout
the day. So all in all rain chances will continue to stay high at
least through Monday night and likely into Tuesday especially over
southwestern Alabama and southeastern Mississippi.

The main threat with these storms will be locally heavy rainfall
given PWATS of 2.5 leading to likely efficient warm rain processes
and rainfall rates likely approaching 2 to 3 inches per hour in
the heaviest bands. Locally heavy rainfall of 3 to 6 inches will
be possible along the coast with some locations getting locally
higher amounts. For instance areas in Tallahassee`s area saw in
excess of 7 inches today where a band setup for a couple of hours.
These higher amounts will be based on where any banding sets up.
Due to this, the flash flood watch will continue for coastal
Alabama, southeast Mississippi, and far western Florida Panhandle.
Along with the rain threat, an isolated tornado threat will be
possible, given we are on the eastern side which typically
supports the higher tornado threat. Luckily we will be removed
from the low-level center and the better backed surface winds will
be displaced to our west. I cannot rule out a tornado or two,
especially during the late afternoon hours tomorrow into early
tomorrow night. Winds will be gusty as well as storms mix down
higher winds associated with the mid-level center. Some showers
could have gusts to 30 to 40 mph.

Luckily with all the rain, temperatures will be on the light side
and will struggle to reach the low 80s. Lows will remain high
though given the increased low level moisture throughout the
period. Rip current risk will remain HIGH for quite some time and
we had reports of 26 beach rescues yesterday at Pensacola beach
alone. The water is not safe and a high surf advisory will also
continue through the period. BB/03
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Nice near term disco by MOB for my area this morning!
NEAR TERM UPDATE /Now Through Tuesday/...As of this morning, theTropical Storm Watch was cancelled for Mobile and BaldwinCounties in Alabama as well as George and Stone counties insoutheast Mississippi. However, windy conditions will be possibletoday. Thus, a Wind Advisory was issued through 7PM CDT thisevening for coastal Mobile and coastal Baldwin counties (mainlyalong the immediate coast) for easterly winds 15-25 mph with gustsup to 35 mph. /26The main point is that the next 48 hours or so will be ratherwet. Marco is currently in a world of absolute hurt as 30 knots ofsouthwesterly shear from the upper trough over the ARKLATEXregion has begun to decouple the low level circulation from themid-level circulation. However as long as there is deep convectionassociated with the mid-level circulation, the low-levelcirculation will continue to attempt to move with the mid-levelcirculation causing the track to potentially shift a little moreeast than originally expected and the NHC`s latest track reflectsthat (about 20 mile eastward shift given the storms position).This really won`t have much of an impact on us as the shear willonly increase with time and the low-levels will eventuallydecouple causing the low-level center to track westward and themid-level center to continue moving north towards our area.Imagine the head of the storm going one way and the legs going theopposite direction. Since the mid-level circulation is expectedto move across the area, a plume of 2 to 2.5 inches PWATs willoverspread the area tonight into Monday. Typically with thesehighly sheared systems most of the rainfall ends up being well tothe east from the actual center and in this situation thats us.Scattered to numerous storms will be expected as lift associatedwith that Mid-level center increases over the area beginning alongthe coast later tonight then slowly spreading inland throughoutthe day. So all in all rain chances will continue to stay high atleast through Monday night and likely into Tuesday especially oversouthwestern Alabama and southeastern Mississippi.The main threat with these storms will be locally heavy rainfallgiven PWATS of 2.5 leading to likely efficient warm rain processesand rainfall rates likely approaching 2 to 3 inches per hour inthe heaviest bands. Locally heavy rainfall of 3 to 6 inches willbe possible along the coast with some locations getting locallyhigher amounts. For instance areas in Tallahassee`s area saw inexcess of 7 inches today where a band setup for a couple of hours.These higher amounts will be based on where any banding sets up.Due to this, the flash flood watch will continue for coastalAlabama, southeast Mississippi, and far western Florida Panhandle.Along with the rain threat, an isolated tornado threat will bepossible, given we are on the eastern side which typicallysupports the higher tornado threat. Luckily we will be removedfrom the low-level center and the better backed surface winds willbe displaced to our west. I cannot rule out a tornado or two,especially during the late afternoon hours tomorrow into earlytomorrow night. Winds will be gusty as well as storms mix downhigher winds associated with the mid-level center. Some showerscould have gusts to 30 to 40 mph.Luckily with all the rain, temperatures will be on the light sideand will struggle to reach the low 80s. Lows will remain highthough given the increased low level moisture throughout theperiod. Rip current risk will remain HIGH for quite some time andwe had reports of 26 beach rescues yesterday at Pensacola beachalone. The water is not safe and a high surf advisory will alsocontinue through the period. BB/03

I can only image the met writing that with a Chesire grin on his face

Sent from my LML212VL using Tapatalk

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@NavarreDon, Imagine.. Your now, (ground(s)) are extremely saturated, and then....
 
 
Having a hurricane ,, Or a very strong TS,,,  landfall..
LOTSA trees/power poles.. (ad-Infinium)  etc are going to come down! 
You have a Generator    right?   

The ground is completely saturated. It wouldn’t take much to bring some trees down as we are closing in on 6”. We are fairly well prepped for weather including an evacuation plan.


.
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The Skyway Bridge fishing pier on Tampa Bay had a 41 mph gust today during a passing line of thunderstorms that may be remotely related to Marco. Looking at other wind reports, I don't see anything near that close to Marco in the northern GOM. We had a 36 mph gust here in Gulfport, Florida and 38 mph gust on Clearwater Beach during the same band of storms.

That is really not uncommon during the thunderstorm season here. But I do think Marco was moving the storm flow across Florida from a distance, even though I may be wrong.

image.thumb.png.0a6d6ade20127b9abf91c171afdb8c8c.png

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