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NHC is now watching another disturbance moving toward the islands for potential development after closing the chapter on the placeholder named T.S. Kyle.

Quote:Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Mon Aug 17 2020

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

1. A fast-moving tropical wave located a couple of hundred miles
east of the Windward Islands continues to produce disorganized
shower and thunderstorm activity. This disturbance is expected to
move westward at about 20 mph during the next few days, and that
fast forward speed is likely to limit significant development while
the system approaches the Windward and southern Leeward Islands
today, and moves across the eastern and central Caribbean Sea on
Tuesday and Wednesday. After that time, however, the system is
expected to move more slowly westward across the western Caribbean
Sea, where upper-level winds could become more conducive for the
development of a tropical depression during the latter part of this
week. Regardless of development, locally heavy rainfall and gusty
winds are expected over portions of the Windward and southern
Leeward Islands beginning today through Tuesday morning.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...medium...50 percent.

[Image: storm_97.gif]
Tropical Depression Fourteen Intermediate Advisory Number 2A
NWS National Hurricane Center Miami FL AL142020
800 PM EDT Thu Aug 20 2020


LOCATION...14.7N 81.7W

Tropical Depression Fourteen Discussion Number 2
NWS National Hurricane Center Miami FL AL142020
500 PM EDT Thu Aug 20 2020

An Air Force Reserve Hurricane Hunter aircraft investigating the
system found an area of lighter winds--likely where the center would
be--farther south than previous estimates. The highest flight-level
wind measured by the aircraft was 30 kt at an altitude of 2500 feet,
and although there were some SFMR measurements over 40 kt, these
looked coincident with some heavy rain rates and thus are probably
not reliable. Therefore, the initial intensity remains 30 kt.
Structurally, the depression has a large cloud envelope with
sporadic convective cells located in loose bands.

The updated initial position derived from the aircraft data
indicates that the current motion is still westward, or 270/16 kt.
This southward adjustment really only affected the first 36 hours
or so of the forecast, with NHC's official track forecast being
shifted southward during that period. This ends up taking the
cyclone's center over extreme northern Nicaragua and northeastern
Honduras in 12-24 hours. After 36 hours, model guidance remains in
good agreement that the system should turn northwestward due to a
deep-layer trough over the Gulf of Mexico. The new set of model
guidance has not shifted much from the previous cycle, and the NHC
track forecast is very close to the morning forecast despite the
initial position adjustment, with perhaps a slight eastward shift
on days 4 and 5. In general, the NHC forecast is closest to the
GFS and HCCA model solutions.

The depression's farther-south position makes the intensity
forecast more complicated with potentially more land interaction
with parts of Central America. Slight strengthening to tropical
storm strength is expected before the center reaches Honduras and
Nicaragua, with little change thereafter until the center
re-emerges over the Gulf of Honduras. Low shear and warm sea
surface temperatures should then support further intensification up
until it reaches the Yucatan Peninsula. Since there is significant
uncertainty in how land interaction will affect the cyclone's
intensity, the forecast intensity has been flat-lined between day 2
and day 4, with the understanding that the the winds could increase
or decrease from the value shown. Vertical shear is expected to
increase by day 5, and some weakening is shown at that time.

Key Messages:

1. Tropical Depression Fourteen is expected to strengthen over the
northwestern Caribbean Sea through Saturday, and is likely to
produce tropical-storm-force winds and heavy rainfall over portions
of the coasts of Nicaragua and Honduras, including the Bay Islands,
beginning tonight through Friday. The system could be near or at
hurricane strength when it reaches the Yucatan Peninsula of Mexico
late Saturday, and watches could be required for a portion of that
area tonight.

2. The system is expected to move into the south-central Gulf
of Mexico as a tropical storm on Sunday. Some strengthening is
anticipated while it moves northwestward over the western Gulf of
Mexico early next week, but it is too soon to know exactly how
strong it will get or the location and magnitude of impacts it
will produce along the central or northwestern Gulf Coast.
Interests in that area should continue monitoring the progress of
this system over the next few days.


INIT 20/2100Z 14.3N 81.0W 30 KT 35 MPH
12H 21/0600Z 14.7N 83.0W 35 KT 40 MPH
24H 21/1800Z 15.6N 84.7W 35 KT 40 MPH...INLAND
36H 22/0600Z 17.0N 85.6W 45 KT 50 MPH...OVER WATER
48H 22/1800Z 18.7N 86.6W 55 KT 65 MPH
60H 23/0600Z 20.3N 87.9W 55 KT 65 MPH...INLAND
72H 23/1800Z 22.1N 89.2W 55 KT 65 MPH...OVER WATER
96H 24/1800Z 26.0N 91.5W 55 KT 65 MPH
120H 25/1800Z 28.5N 93.5W 50 KT 60 MPH
2020 just keeps getting better and better...
[Image of probabilities of 34-kt winds]
[Image: storm_14.gif]
WTNT44 KNHC 231457

Tropical Storm Marco Discussion Number 13
NWS National Hurricane Center Miami FL AL142020
1000 AM CDT Sun Aug 23 2020

Deep convection with cloud tops of -75 to -80 degrees C has
persisted over the center of Marco for the past several hours. An
Air Force Reserve Hurricane Hunter aircraft currently investigating
the cyclone measured winds equivalent to 62 kt both with the SFMR
and in a dropsonde in the northeastern eyewall. However, the
aircraft reported peak 850-mb flight level winds of only 64 kt.
Based on a blend of these data it appears that Marco is on the cusp
of becoming a hurricane, but is not quite there yet. Therefore, the
initial intensity remains 60 kt.

Based on the SHIPS guidance, Marco has about a 12-24 hour window to
intensify in an environment characterized by moderate southwesterly
shear, very warm waters, and plenty of atmospheric moisture. After
that time, the vertical wind shear is expected to increase and this
should begin to dominate the cyclone's environment. The latest NHC
intensity forecast is unchanged from the previous one, forecasting
Marco to become a hurricane later today, and maintaining hurricane
intensity up until landfall in agreement with the latest LGEM
intensity guidance. While it is possible that Marco will weaken just
prior to landfall due to the increasing shear, there is little
difference in the impacts between a 60 and 65 kt system.

Marco is moving north-northwestward or 340/12 kt. Although the
overall guidance has not changed much since the previous advisory,
there remains considerable spread in this guidance by the time Marco
reaches the northern Gulf coast. This spread could be attributed to
the varying ways the models handle the system as it encounters the
more hostile environment near the coast. Since the track consensus
aids have changed little through 36 h, the official forecast is
essentially the same as the previous one through that time. The
model guidance has shifted a little northward beyond 36 h, so the
official forecast was nudged to the north during that time as well.

Key Messages:

1. Hurricane conditions, life-threatening storm surge, and heavy
rainfall are expected from Marco along portions of the Gulf Coast
beginning on Monday, and Hurricane and Storm Surge Warnings have
been issued. 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.


INIT 23/1500Z 24.7N 87.3W 60 KT 70 MPH
12H 24/0000Z 26.4N 88.1W 65 KT 75 MPH
24H 24/1200Z 28.2N 89.1W 65 KT 75 MPH
36H 25/0000Z 29.5N 90.4W 55 KT 65 MPH...INLAND
48H 25/1200Z 30.5N 92.1W 35 KT 40 MPH...INLAND
60H 26/0000Z 31.2N 93.8W 30 KT 35 MPH...INLAND
72H 26/1200Z 31.8N 95.4W 25 KT 30 MPH...INLAND
96H 27/1200Z...DISSIPATED

Forecaster Latto
now a cane !
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