old/2018/gordon.dis

WTNT42 KNHC 031236
TCDAT2

Tropical Storm Gordon Special Discussion Number   4
NWS National Hurricane Center Miami FL       AL072018
830 AM EDT Mon Sep 03 2018

Surface observations from the Florida Keys and southeast Florida,
along with Doppler velocity data from the Miami radar, indicate
that the disturbance has developed a closed surface circulation and
a well-defined center. Recent observations from a Weatherflow site
at Carys Fort Reef and radar data support increasing the maximum
winds to at least 40 kt. As a result of these data, the system has
been upgraded to Tropical Storm Gordon, the seventh named system of
the 2018 Atlantic hurricane season. An Air Force Reserve Unit
reconnaissance aircraft is enroute to investigate Gordon.

The initial motion estimate is 300/15 kt and the previous forecast
track remains unchanged. The intensity forecast was adjusted upward
in the first 24 to 36 hours to account for the initial increase in
intensity. Some additional adjustments may be required after the
reconnaissance aircraft completes its mission and provides more
detailed information on the stricture and intensity of Gordon.

Key Messages:

1. Gordon will bring heavy rainfall and tropical storm conditions to
portions of South Florida and the Florida Keys today and a Tropical
Storm Warning is in effect for these areas.

2. A Tropical Storm Warning is in effect for portions of the
central Gulf Coast, and tropical storm conditions are expected in
those areas beginning late Tuesday.  Heavy rainfall from Gordon will
affect portions of the central Gulf Coast over the next few days,
including areas that have already received heavy rainfall from a
different weather system.  Interests in these areas should monitor
products from their local National Weather Service office.

FORECAST POSITIONS AND MAX WINDS

INIT  03/1230Z 25.1N  80.7W   40 KT  45 MPH
 12H  03/1800Z 25.7N  82.1W   45 KT  50 MPH
 24H  04/0600Z 27.2N  84.8W   50 KT  60 MPH
 36H  04/1800Z 28.8N  87.4W   50 KT  60 MPH
 48H  05/0600Z 30.4N  89.7W   50 KT  60 MPH
 72H  06/0600Z 33.0N  92.7W   30 KT  35 MPH...INLAND
 96H  07/0600Z 34.0N  95.0W   25 KT  30 MPH...INLAND
120H  08/0600Z 35.5N  96.0W   20 KT  25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Stewart


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WTNT42 KNHC 031455
TCDAT2

Tropical Storm Gordon Discussion Number   5
NWS National Hurricane Center Miami FL       AL072018
1100 AM EDT Mon Sep 03 2018

Surface observations from the Florida Keys and southeast Florida,
along with Doppler velocity data from the Miami radar, indicate that
Gordon has continued to become organized this morning. The center
of the cyclone passed over Key Largo between 1100-1200 UTC,
producing a west wind in Islamorada and also at an observing site
in Florida Bay. Doppler velocity data and surface observations
support an intensity of 40 kt for this advisory. An Air Force
Reserve Unit reconnaissance aircraft is currently investigating
Gordon.

The initial motion estimate is 300/14 kt. The latest model
guidance has shifted slightly to the right, but this is likely due
to the more northerly initial position. Other than that, the models
remain tightly packed and agree on a general west-northwestward to
northwestward motion for the next 48 hours right up until landfall
as the strong ridge to the north of Gordon moves little. The new NHC
forecast track was adjusted a little to the right of the previous
advisory track, but not as far to the east as some of the model
guidance out of respect for the reliable ECMWF deterministic run,
which is located on the southern edge of the guidance and shows
landfall near the mouth of the Mississippi River, a solution that is
also supported by the new 0600Z short-range UKMET model run.

Gordon's appearance in both radar and satellite imagery has
continued to improve over the past several hours. The GFS- and
ECMWF-based SHIPS models indicate that westerly to northwesterly
vertical wind shear of about 10 kt is allegedly affecting Gordon,
but there are no indications of that in satellite imagery that I
can see. The cirrus outflow has continued to expand in all
quadrants, so the analyzed westerly shear is likely an artifact of
the small circulation being positioned so close to the strong trough
located its west. Since Gordon will be moving over sea-surface
temperatures near 30 deg C during the next 36-48 hours, and be near
or underneath an upper-level anticyclone, steady strengthening seems
likely. It is possible that Gordon could peak as a Category 1
hurricane after 36 hours, just before landfall occurs. For that
reason, a Hurricane Watch has been issued for portions of the
central Gulf Coast. The new intensity forecast is above the previous
advisory, and is close to a blend of the consensus models
HCCA, FSSE, and IVCN.

Key Messages:

1. Gordon will bring heavy rainfall and tropical storm conditions
to portions of South Florida and the Florida Keys today and a
Tropical Storm Warning remains in effect for these areas.

2. Gordon is expected to bring life-threatening storm surge to
portions of the central Gulf Coast and a Storm Surge Warning has
been issued from the Mouth of the Pearl River to the Mississippi-
Alabama border. Residents in these areas should listen to advice
from their local officials and all preparations to protect life
and property should be rushed to completion.

3. A Tropical Storm Warning and Hurricane Watch are in effect for
portions of the central Gulf Coast. Tropical storm conditions are
expected to reach those areas late Tuesday, with hurricane
conditions possible in the watch area.

4. Heavy rainfall from Gordon will affect southern Alabama, southern
Mississippi and Louisiana, where totals could reach as high as 8
inches. This rainfall could cause flash flooding.

FORECAST POSITIONS AND MAX WINDS

INIT  03/1500Z 25.3N  81.3W   40 KT  45 MPH
 12H  04/0000Z 26.5N  83.4W   45 KT  50 MPH
 24H  04/1200Z 28.1N  86.0W   50 KT  60 MPH
 36H  05/0000Z 29.9N  88.4W   60 KT  70 MPH
 48H  05/1200Z 31.3N  90.3W   40 KT  45 MPH...INLAND
 72H  06/1200Z 33.9N  93.2W   25 KT  30 MPH...INLAND
 96H  07/1200Z 34.8N  94.9W   20 KT  25 MPH...INLAND
120H  08/1200Z 37.6N  95.1W   20 KT  25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Stewart


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WTNT42 KNHC 032052
TCDAT2

Tropical Storm Gordon Discussion Number   6
NWS National Hurricane Center Miami FL       AL072018
500 PM EDT Mon Sep 03 2018

Data from an earlier Air Force Reserve reconnaissance mission, along
with Doppler velocity data from the Miami radar, indicate that
Gordon has strengthened a little more, with some these data
supporting an intensity of about 50 kt. However, since the earlier
5-n mi-diameter eye has eroded and inner-core convection has become
somewhat ragged, the initial intensity remains 45 kt.

The initial motion estimate is 300/15 kt. The latest model guidance
is still in excellent agreement on Gordon maintaining a west-
northwestward to northwestward motion for the next 48-72 hours right
up until landfall as a strong ridge to the north of the cyclone is
forecast to remain locked in place over the southeastern U.S. and
mid-Atlantic states. Although the guidance has shifted slightly back
to the left, no appreciable changes were made to the previous
forecast track since the models have been 'windshield-wipering' back
and forth over the past 24 hours. The new NHC track forecast is
similar to or a little north of the latest consensus models.

Overall, Gordon's presentation in both radar and satellite imagery
has steadily improved since the previous advisory. Although the
inner-core structure has eroded somewhat, outer banding features
have improved and now extend as far north as central and northern
Florida. The GFS- and ECMWF-based SHIPS intensity models continue to
indicate that westerly to northwesterly wind shear of 10-15 kt is
expected to affect Gordon for the next 36 hours, a flow pattern that
would generally hinder development. However, the global models'
upper-level wind fields show Gordon remaining near or underneath a
synoptic-scale upper-level anticyclone, a more favorable pattern
that supports at least steady strengthening. Since Gordon will be
moving over very warm sea-surface temperatures of about 30 C, the
cyclone is forecast to reach hurricane strength in 24-36 hours, just
before landfall. For that reason, a Hurricane Warning has been
issued for portions of the central Gulf Coast. The NHC intensity
forecast is a little above the previous advisory, and is close to a
blend of the consensus models HCCA, FSSE, and IVCN.

Key Messages:

1. Gordon is expected to bring life-threatening storm surge and
hurricane conditions to portions of the central Gulf Coast where a
Storm Surge Warning and Hurricane Warning are in effect. Residents
in these areas should listen to advice from their local officials.
All preparations to protect life and property should be rushed to
completion, as tropical storm conditions are expected to arrive in
the warning areas Tuesday afternoon or evening.

2. Heavy rainfall from Gordon will affect southern Alabama, southern
Mississippi and Louisiana, where totals could reach as high as 8
inches. This rainfall could cause flash flooding.

3. Rainfall will continue across portions of South Florida and the
Florida Keys through early Tuesday, where totals could reach as high
as 8 inches.

FORECAST POSITIONS AND MAX WINDS

INIT  03/2100Z 26.2N  82.6W   45 KT  50 MPH
 12H  04/0600Z 27.3N  84.8W   50 KT  60 MPH
 24H  04/1800Z 28.9N  87.2W   60 KT  70 MPH
 36H  05/0600Z 30.6N  89.3W   65 KT  75 MPH...INLAND
 48H  05/1800Z 32.1N  91.1W   35 KT  40 MPH...INLAND
 72H  06/1800Z 34.1N  93.5W   25 KT  30 MPH...INLAND
 96H  07/1800Z 35.5N  94.8W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  08/1800Z 38.2N  94.8W   20 KT  25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Stewart


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WTNT42 KNHC 040247
TCDAT2

Tropical Storm Gordon Discussion Number   7
NWS National Hurricane Center Miami FL       AL072018
1100 PM EDT Mon Sep 03 2018

WSR-88D radar data from Tampa shows that the small inner core of
Gordon has lost some organization during the past few hours, and
GOES-16 satellite imagery and recent aircraft fixes indicate that
the low-level center is located near the southwestern edge of the
main convective mass.  This suggests that there may be some light to
moderate westerly shear affecting the cyclone.  The Air Force
Reserve reconnaissance aircraft recently measured peak 850-mb
flight-level winds of 57 kt, and SFMR winds of 50-55 kt.  A blend
of these data yields an initial wind speed estimate of 50 kt.

A UW/CIMSS shear analysis and the SHIPS model indicates that there
is about 10-15 kt of westerly shear over the system.  The SHIPS
guidance shows a slight relaxation of the shear during the next
12-18 hours while the system moves over the warm waters of the Gulf
of Mexico, which should allow for some strengthening.  However,
Gordon is a small tropical cyclone and subtle changes in shear
(both up and down) can result in fairly quick intensity changes for
systems like this.  The NHC intensity forecast assumes that shear
will not be prohibitive and that Gordon will become a hurricane
before reaching the northern Gulf coast.  The NHC intensity
forecast is close to the SHIPS guidance through 24 hours, then
follows the HFIP corrected consensus after landfall which shows
Gordon weakening rapidly over land.

Gordon is moving west-northwestward at about 15 kt.  The tropical
storm is expected to maintain a west-northwestward to northwestward
heading during the next few days while it moves around the
southwestern portion of a large deep-layer ridge centered over the
Mid-Atlantic states.  After that time, the cyclone should decelerate
as it moves around the western periphery of the ridge.  The track
guidance continues to be tightly clustered through 72 h, and no
significant changes were required to the previous NHC track
forecast.

Key Messages:

1. Gordon is expected to bring life-threatening storm surge and
hurricane conditions to portions of the central Gulf Coast where a
Storm Surge Warning and Hurricane Warning are in effect. Residents
in these areas should listen to advice from their local officials.
All preparations to protect life and property should be rushed to
completion, as tropical storm conditions are expected to arrive in
the warning areas Tuesday afternoon.

2. Heavy rainfall from Gordon will affect southern Alabama, southern
Mississippi and Louisiana, where totals could reach as high as 8
inches. This rainfall could cause flash flooding.

FORECAST POSITIONS AND MAX WINDS

INIT  04/0300Z 26.9N  84.3W   50 KT  60 MPH
 12H  04/1200Z 28.3N  86.3W   55 KT  65 MPH
 24H  05/0000Z 30.0N  88.6W   65 KT  75 MPH
 36H  05/1200Z 31.6N  90.3W   40 KT  45 MPH...INLAND
 48H  06/0000Z 32.9N  91.6W   25 KT  30 MPH...INLAND
 72H  07/0000Z 34.6N  93.9W   20 KT  25 MPH...INLAND
 96H  08/0000Z 36.5N  94.9W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  09/0000Z 39.5N  93.0W   20 KT  25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Brown


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WTNT42 KNHC 040847
TCDAT2

Tropical Storm Gordon Discussion Number   8
NWS National Hurricane Center Miami FL       AL072018
400 AM CDT Tue Sep 04 2018

Gordon has changed little in organization on geostationary
satellite images or on the WSR-88D radar presentation over the past
several hours.  The storm has a small CDO with convective banding
features primarily over the eastern semicircle of the circulation.
Overall the cloud pattern is indicative of moderate westerly shear
over the system, likely associated with an upper-level trough near
the central Gulf of Mexico.  An Air Force Reserve Unit Hurricane
Hunter aircraft investigated Gordon a few hours ago and reported
maximum SFMR-measured surface winds of 54 kt.  On this basis the
intensity had been adjusted to 55 kt, which is somewhat above the
latest Dvorak estimates.  It is assumed that the shear will not be
strong enough to inhibit at least some strengthening before
landfall, so the tropical cyclone is still forecast to become a
hurricane later today.  The official forecast, prior to landfall, is
close to the latest LGEM intensity guidance, and near the upper end
of the guidance suite.  Gordon should weaken rapidly after landfall
in the lower Mississippi Valley region.

The motion continues west-northwestward, or 300/15 kt.  There is
little or no change to the NHC track prediction or forecast
reasoning from the previous advisory.  Gordon is expected to move
along the southwestern periphery of a mid-level high pressure area
and make landfall along the north-central Gulf of Mexico coast
within 24 hours.  After landfall, the cyclone is forecast to move
northwestward, along the western side of the high, at a reduced
forward speed.  Late in the forecast period Gordon, or its
post-tropical remnant, should turn northward to north-northeastward
as it approaches the mid-latitude westerlies.  The official track
forecast is near the model consensus and very close to the previous
NHC track.

Key Messages:

1. Gordon is expected to bring life-threatening storm surge and
hurricane conditions to portions of the central Gulf Coast where a
Storm Surge Warning and Hurricane Warning are in effect.  Residents
in these areas should listen to advice from their local officials.
All preparations to protect life and property should be rushed to
completion, as tropical storm conditions are expected to arrive in
the warning areas this afternoon.

2. Heavy rainfall from Gordon will affect the western Florida
Panhandle, southern  Alabama, southern Mississippi and Louisiana,
where totals could reach as high as 12 inches.  This rainfall could
cause flash flooding.

FORECAST POSITIONS AND MAX WINDS

INIT  04/0900Z 27.7N  85.7W   55 KT  65 MPH
 12H  04/1800Z 29.0N  87.5W   65 KT  75 MPH
 24H  05/0600Z 30.7N  89.6W   55 KT  65 MPH...INLAND
 36H  05/1800Z 32.2N  91.0W   35 KT  40 MPH...INLAND
 48H  06/0600Z 33.4N  92.3W   25 KT  30 MPH...INLAND
 72H  07/0600Z 34.9N  94.3W   20 KT  25 MPH...POST-TROP/REMNT LOW
 96H  08/0600Z 37.0N  94.5W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  09/0600Z 40.0N  92.0W   20 KT  25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Pasch


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WTNT42 KNHC 041450
TCDAT2

Tropical Storm Gordon Discussion Number   9
NWS National Hurricane Center Miami FL       AL072018
1000 AM CDT Tue Sep 04 2018

After an earlier disruption of the inner-core convection due to some
southerly wind shear, Gordon has since developed a band of deep
convection very near the well-defined center noted in both NOAA
GOES-16 high-resolution satellite imagery and coastal NOAA WSR-88D
Doppler radars.  In addition, there has been a significant increase
in lightning activity during the past couple of hours in the inner
core, and Doppler radar velocities have increased to more than 45 kt
at 25,000 ft in the band of convection near the center. NOAA and Air
Force Reserve reconnaissance aircraft further indicate that Gordon
has maintained a small radius of maximum winds (RMW) of 10-15 nmi,
and that SFMR surface winds of 53-55 kt exist in the northeastern
quadrant. These data support an intensity of 55 kt.

The initial motion estimate is now toward the northwest at a
slightly slower forward, or 305/13 kt. There is basically no change
to the previous NHC forecast track reasoning. Reconnaissance fixes
continue to fall along the previous forecast track, and the latest
model guidance remains tightly packed and on top of the previous
NHC forecast. As a result, there is high confidence that Gordon will
make landfall along the north-central Gulf of Mexico coast in about
18 hours. After landfall, steering currents are forecast to weaken,
resulting in Gordon slowing down considerably, which will enhance
the heavy rainfall potential. By Friday, an approaching cold front
and associated mid-/upper-level trough are expected to break down
the subtropical ridge, allowing Gordon to turn northward and
eventually turn northeastward on Saturday and merge with the cold
front. The new official track forecast is near the model consensus
and essentially on top of the previous NHC track.

The aforementioned inner-core changes that have been occurring could
be a harbinger that Gordon is finally starting to intensify. Intense
lightning activity inside the small RMW is an indication of strong
updrafts, which can enhance the strengthening process. Although the
GFS and ECMWF models continue to forecast northwesterly shear of
10-15 kt, the explicit upper-level wind fields in the GFS, ECMWF,
and UKMET models indicate that the 200-mb flow is forecast to become
southeasterly and diffluent across Gordon in the next 12 h or so,
which would act to enhance the development of inner-core convection.
As result, the official intensity forecast maintains continuity and
shows Gordon becoming a hurricane before landfall, which is above
the guidance through that time. Once Gordon moves inland, the small
circulation should spin down fairly quickly, and that portion of the
forecast closely follows the various consensus-model intensity
guidance. By 120 h, Gordon's circulation is expected to merge with a
cold front over the Mississippi Valley region.

Key Messages:

1. Gordon is expected to bring life-threatening storm surge and
hurricane conditions to portions of the central Gulf Coast where a
Storm Surge Warning and Hurricane Warning are in effect. Residents
in these areas should listen to advice from their local officials.

2. Heavy rainfall from Gordon will affect the western Florida
Panhandle, southwest Alabama, southern and central Mississippi,
much of eastern Louisiana, and southern Arkansas, where totals could
reach as high as 12 inches. This rainfall will cause flash flooding
in portions of these areas.

FORECAST POSITIONS AND MAX WINDS

INIT  04/1500Z 28.5N  86.8W   55 KT  65 MPH
 12H  05/0000Z 29.8N  88.5W   65 KT  75 MPH
 24H  05/1200Z 31.5N  90.2W   35 KT  40 MPH...INLAND
 36H  06/0000Z 32.8N  91.6W   25 KT  30 MPH...INLAND
 48H  06/1200Z 33.7N  92.7W   20 KT  25 MPH...INLAND
 72H  07/1200Z 35.4N  94.3W   20 KT  25 MPH...POST-TROP/REMNT LOW
 96H  08/1200Z 37.7N  93.8W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  09/1200Z 40.9N  90.7W   20 KT  25 MPH...POST-TROP/EXTRATROP

$$
Forecaster Stewart


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WTNT42 KNHC 042051
TCDAT2

Tropical Storm Gordon Discussion Number  10
NWS National Hurricane Center Miami FL       AL072018
400 PM CDT Tue Sep 04 2018

Gordon has been undergoing another convective bursting phase during
the past few hours, with a sharp increase in Doppler velocity
values noted between 9,000-12,000 ft. Some peak velocity values
have been in excess of 80 kt, but average values have been around
65-67 kt, which supports an advisory intensity of 60 kt. Another
reconnaissance mission will be conducted in Gordon in a few hours,
which provide additional intensity and pressure data.

The initial motion estimate is 310/13 kt. There remains no
significant change to the previous NHC forecast track or reasoning.
The new model guidance has shifted slightly to the east, but not
enough to make any appreciable changes to the previous forecast
track. As a result, Gordon is expected to move northwestward toward
the Mississippi coastline, and the cyclone will make landfall in
that area around 0300 UTC. After landfall, steering currents are
still expected to weaken, causing Gordon to slow down considerably.
The slower forward speed, which will be near 5 kt at times, will act
to enhance the heavy rainfall potential. By Friday, a mid- to
upper-level trough and a cold front are forecast to cause a break
int the subtropical ridge, allowing Gordon to turn northward on
Friday, and move northeastward on Saturday. Gordon's remnant
circulation is expected to merge with a cold front by Sunday. The
new official track forecast is close to a blend of the consensus
models HCCA, FSSE, and TVCA,

Gordon still has another 6 hours or so over warm waters near 30C,
which in combination with an upper-level environment of diffluent
southeasterly upper-level flow and increased surface convergence due
to land interaction will provide a brief window of opportunity for
Gordon to reach hurricane strength before landfall. Once Gordon
moves inland, the small circulation is expected to spin down
quickly, with Gordon becoming a remnant low by 48 hours.

Key Messages:

1. Gordon is expected to bring life-threatening storm surge and
hurricane conditions to portions of the central Gulf Coast, where a
Storm Surge Warning and Hurricane Warning are in effect. The highest
storm surge is expected along the coasts of Mississippi and Alabama
from the Mouth of the Pearl River to Dauphin Island tonight and
early Wednesday. Tropical storm conditions and storm surge will also
affect portions of the western Florida Panhandle.

2. Heavy rainfall from Gordon will affect the western Florida
Panhandle, southwest Alabama, southern and central Mississippi,
northeastern Louisiana, and southern Arkansas, where totals could
reach as high as 12 inches. This rainfall will cause flash flooding
in portions of these areas.

FORECAST POSITIONS AND MAX WINDS

INIT  04/2100Z 29.4N  87.8W   60 KT  70 MPH
 12H  05/0600Z 30.7N  89.3W   55 KT  65 MPH...INLAND
 24H  05/1800Z 32.2N  90.7W   30 KT  35 MPH...INLAND
 36H  06/0600Z 33.2N  91.9W   25 KT  30 MPH...INLAND
 48H  06/1800Z 34.0N  93.0W   20 KT  25 MPH...POST-TROP/REMNT LOW
 72H  07/1800Z 35.7N  94.1W   20 KT  25 MPH...POST-TROP/REMNT LOW
 96H  08/1800Z 38.1N  93.1W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  09/1800Z 41.0N  89.5W   20 KT  25 MPH...POST-TROP/EXTRATROP

$$
Forecaster Stewart


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WTNT42 KNHC 050258
TCDAT2

Tropical Storm Gordon Discussion Number  11
NWS National Hurricane Center Miami FL       AL072018
1000 PM CDT Tue Sep 04 2018

Aircraft and radar imagery shows that the center of Gordon is
making landfall just west of the Alabama-Mississippi border.  The
radar imagery has shown an increase in convection around the center
within the past couple of hours, and Doppler velocities have
increased to 65-75 kt at about 2500 feet.  A NOAA Hurricane Hunter
aircraft has measured peak 700-mb flight-level winds of 63 kt.
These data support an initial intensity of 60 kt.  A NOAA Coastal
Marine Observing site on Dauphin Island, Alabama has recently
reported sustained winds of 49 kt with a gust to 63 kt.  Once the
center moves inland, Gordon should rapidly weaken and it is
forecast to become a tropical depression on Wednesday morning.

Gordon moved a little right of the previous forecast track this
evening, but the most recent aircraft fixes suggest the center has
jogged back toward the left. The longer-term motion estimate is
315/12 kt.  A large deep-layer ridge located over the eastern
United States is forecast to steer Gordon northwestward at a slower
forward speed during the next couple of days.  After that time, the
cyclone should turn northward, then northeastward around the
western periphery of the ridge.  The updated NHC track is again
close to a blend of the various consensus aids, but is a little
right of previous forecast for the first 24-36 hours, primarily due
to the slightly more eastward initial position.

Key Messages:

1. Gordon is expected to bring life-threatening storm surge and
hurricane conditions to portions of the central Gulf Coast, where a
Storm Surge Warning and Hurricane Warning are in effect. The highest
storm surge is expected along the coasts of Mississippi and Alabama
from Biloxi to Dauphin Island tonight and early Wednesday. Tropical
storm conditions and storm surge will also affect portions of the
western Florida Panhandle.

2. Heavy rainfall from Gordon will affect the western Florida
Panhandle, southwest Alabama, southern and central Mississippi,
northeastern Louisiana, and southern Arkansas, where totals could
reach as high as 12 inches. This rainfall will cause flash flooding
in portions of these areas.


FORECAST POSITIONS AND MAX WINDS

INIT  05/0300Z 30.3N  88.4W   60 KT  70 MPH
 12H  05/1200Z 31.5N  89.6W   35 KT  40 MPH...INLAND
 24H  06/0000Z 32.7N  90.9W   25 KT  30 MPH...INLAND
 36H  06/1200Z 33.5N  92.0W   25 KT  30 MPH...INLAND
 48H  07/0000Z 34.3N  92.9W   20 KT  25 MPH...POST-TROP/REMNT LOW
 72H  08/0000Z 36.0N  93.9W   20 KT  25 MPH...POST-TROP/REMNT LOW
 96H  09/0000Z 38.3N  92.0W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  10/0000Z 41.0N  88.5W   20 KT  25 MPH...POST-TROP/EXTRATROP

$$
Forecaster Brown


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WTNT42 KNHC 050854
TCDAT2

Tropical Storm Gordon Discussion Number  12
NWS National Hurricane Center Miami FL       AL072018
400 AM CDT Wed Sep 05 2018

Gordon is moving farther inland and continues to weaken.  Surface
synoptic observations suggest that the cyclone is now of, at most,
minimal tropical storm strength.  These tropical-storm-force winds
may be occurring over a small inland area near the center.
Continued weakening is expected, and Gordon should become a
tropical depression later this morning.

Gordon continues moving northwestward, with an initial motion
estimate of 325/12.  The cyclone should continue on a northwestward
heading with a decrease in forward speed, along the southwestern
periphery of a mid-level ridge, for the next couple of days.  Later
in the period, Gordon's remnant is forecast to turn northward
and northeastward with increasing forward speed as it approaches
the mid-latitude westerlies north of 40N.  the official forecast
track is close to the latest dynamical model consensus, TVCA.

All coastal watches and warnings associated with Gordon are being
discontinued at this time.


Key Messages:

1. Heavy rainfall from Gordon will affect the western Florida
Panhandle, southwest Alabama, southern and central Mississippi,
northeastern Louisiana, Arkansas, Missouri, southern Iowa and
Illinois, with isolated maximum amounts of 12 inches through early
Saturday.  This rainfall will cause flash flooding across portions
of these areas.

FORECAST POSITIONS AND MAX WINDS

INIT  05/0900Z 31.5N  89.5W   35 KT  40 MPH
 12H  05/1800Z 32.4N  90.4W   25 KT  30 MPH...INLAND
 24H  06/0600Z 33.4N  91.6W   25 KT  30 MPH...INLAND
 36H  06/1800Z 34.1N  92.5W   25 KT  30 MPH...INLAND
 48H  07/0600Z 34.8N  93.3W   20 KT  25 MPH...POST-TROP/REMNT LOW
 72H  08/0600Z 36.7N  93.6W   20 KT  25 MPH...POST-TROP/REMNT LOW
 96H  09/0600Z 39.0N  91.0W   20 KT  25 MPH...POST-TROP/EXTRATROP
120H  10/0600Z 42.0N  86.0W   20 KT  25 MPH...POST-TROP/EXTRATROP

$$
Forecaster Pasch


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WTNT42 KNHC 051432
TCDAT2

Tropical Depression Gordon Discussion Number  13
NWS National Hurricane Center Miami FL       AL072018
1000 AM CDT Wed Sep 05 2018

Surface observations and WSR-88D Doppler radar data indicate that
Gordon continues to weaken as it passes near Jackson, Mississippi,
and the initial intensity has been reduced to a possibly generous
25 kt. Additional weakening is expected as the cyclone moves farther
inland, and it is expected to decay to a remnant low pressure area
in about 48 h. The remnant low is then expected to become
extratropical as it merges with a frontal zone over the central
United States by Saturday. Although Gordon has weakened, the threat
of heavy rainfall and flooding will continue for the next few days.

The initial motion estimate is 320/12.  Gordon should continue
northwestward with a decrease in forward speed during the next 48 h
as it moves along the southwestern side of a mid-level ridge.  After
that, the cyclone or its remnants are expected to turn northward and
northeastward as it recurves into the westerlies.  The new forecast
track is similar to the previous one.  However, during the first
48 h it lies to the east of the various consensus models due to a
westward shift in the guidance since the last advisory.

This will be the last advisory issued by the National Hurricane
Center on Gordon.  Future information on Gordon can be found
in Public Advisories issued by the Weather Prediction Center
beginning at 4 PM CDT, under AWIPS header TCPAT2, WMO header WTNT32
KWNH, and on the web at https://www.wpc.ncep.noaa.gov.

Key Messages:

1. Even though Gordon is weakening, heavy rainfall will continue to
affect the western Florida Panhandle, southwest Alabama, central
Mississippi, Arkansas, Missouri, southern Iowa and Illinois, with
isolated maximum amounts of 12 inches possible.  This rainfall will
cause flash flooding across portions of these areas.

FORECAST POSITIONS AND MAX WINDS

INIT  05/1500Z 32.3N  90.2W   25 KT  30 MPH...INLAND
 12H  06/0000Z 33.3N  91.1W   25 KT  30 MPH...INLAND
 24H  06/1200Z 33.9N  92.2W   20 KT  25 MPH...INLAND
 36H  07/0000Z 34.5N  93.0W   20 KT  25 MPH...INLAND
 48H  07/1200Z 35.3N  93.6W   20 KT  25 MPH...POST-TROP/REMNT LOW
 72H  08/1200Z 37.0N  93.5W   20 KT  25 MPH...POST-TROP/EXTRATROP
 96H  09/1200Z 39.5N  90.0W   20 KT  25 MPH...POST-TROP/EXTRATROP
120H  10/1200Z 43.0N  84.0W   20 KT  25 MPH...POST-TROP/EXTRATROP

$$
Forecaster Beven


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