October 2017 - Halloween Forecast/Rain Chances

General Weather Discussions and Analysis
unome
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72-hr surface forecast with 96-hr position

http://www.nhc.noaa.gov/marine/forecast ... /GOM72.gif
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Last edited by unome on Thu Oct 05, 2017 7:05 pm, edited 1 time in total.
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srainhoutx
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Tuesday evening briefing from Jeff:

Tropical system is organizing in the SW Caribbean Sea…expected to move into the Gulf of Mexico and threaten the US Gulf coast.

An area of low pressure has formed in the extreme SW Caribbean Sea today and recent satellite images suggest that a tropical cyclone is gradually forming with a large curved band of convection having developed. There is no well defined center at this time, but instead a large broad area of circulation. Overall the system is organizing as it moves toward the NNW. The NHC currently gives the system a 70% chance of formation over the next 5 days.

Track:
90L will track NNW to NW over the next 24-48 hours and across the western and into the northwest Caribbean Sea and then continue into the SC Gulf of Mexico this weekend. A strong trough of low pressure (common in October) will sweep into the northern plains this weekend and break down the ridging across the US Gulf coast allowing any tropical system over the Gulf to turn northward and likely accelerate toward the coast by late this weekend. Operational forecast models and their ensemble tracks suggest a threat from SW Louisiana to the FL panhandle with what appears to be the greatest threat from SE LA to the central FL panhandle.

With the lack of any defined low level center and the critical timing elements over the Gulf of Mexico this weekend, residents along the US Gulf coast should remain alert for the potential for a potential tropical storm or hurricane in the Gulf.

Intensity:
GFS and ECMWF have shown a more aggressive forecast today with 90L compared to the previous runs and western Caribbean Sea tropical cyclones in October should always be watched closely given usually very favorable conditions and extremely warm waters. Based on satellite images it appears a tropical storm may form over the next 24-36 hours as the system moves into the western Caribbean Sea and then conditions appear at least generally favorable for continued intensification across the Gulf of Mexico.
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srainhoutx
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I am liking the overnight trends regarding our Tropical Disturbance 90L, The track guidance looks fairly straight forward the 90L will slowly move NNW into the Southern Gulf before it feels the rather strong full latitude trough digging S and E across the Central United States early next week.
10042017 8 AM TWO two_atl_5d0.png
Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Wed Oct 4 2017

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

1. Showers and thunderstorms associated with an area of low pressure
located over the southwestern Caribbean Sea have become better
organized since yesterday. This system is expected to become a
tropical depression later today while it moves northwestward toward
the coast of Nicaragua. The low should move slowly northwestward
across or near the eastern portions of Nicaragua and Honduras on
Thursday, move into the northwestern Caribbean Sea by Friday, and
emerge over the southern Gulf of Mexico by Saturday. Interests in
Nicaragua, Honduras, the Yucatan peninsula and western Cuba should
monitor the progress of this system as watches or warnings could be
issued later today. An Air Force Reserve reconnaissance aircraft is
scheduled to investigate the disturbance this afternoon. Regardless
of development, this system will produce heavy rains over portions
of Central America during the next few days, likely causing flash
floods and mudslides.
* Formation chance through 48 hours...high...90 percent.
* Formation chance through 5 days...high...90 percent.


10042017_1130Z_goes13_x_ir1km_90LINVEST_25kts-1007mb-118N-813W_87pc.jpg
10042017 06Z 90L 90L_tracks_06z.png
10042017 00Z 96 ecmwf_z500aNorm_namer_5.png
10042017 00Z 120 ecmwf_z500aNorm_namer_6.png
As can be very typical with these October Tropical Systems, cold air can get pulled rather far South as the TC exits NE and if the 00Z ECMWF is correct, breezy NW winds and Fall Like Temperatures will invade our Region Tuesday into Wednesday. Fingers Crossed!!
10042017 00Z 168 ecmwf_T850a_namer_8.png
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658
FXUS64 KHGX 040914
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
414 AM CDT Wed Oct 4 2017

.DISCUSSION...
Only a few showers dot the area early this morning as high pressure
has begun to build in from the northeast. Our air mass will continue
to get drier as the day progresses, and a majority of the area will
have a dry and warm day (cannot totally rule out an isolated shower
or thunderstorm mainly along and south of the Interstate 10 corridor).
A mostly dry and warm weather pattern will prevail across Southeast
Texas for the remainder of the week and on through at least the first
half of the upcoming weekend. Some changes in the forecast could come
over the next several days as we watch how the tropical disturbance
in the southwest Caribbean develops and moves into the Gulf of Mexico
(as always, consult the latest information from the National Hurricane
Center). For now, will base our forecast on keeping this system and
its associated rains off to our east. Low rain chances come back into
our forecast at the start of next week as moisture levels rise ahead
of a cold front. Models continue to differ on the timing and strength
of this frontal passage. For now, we are showing the boundary and
associated wind shift entering the area late Monday night and moving
through the area and off the coast on Tuesday with increasing north
winds and cooler temperatures developing in its wake.
42
&&

.MARINE...
East winds currently 20-30kt continue to pile water up along the
coastline along with elevated seas, surf, & rip currents. We`re
going into high tide shortly and it looks like observed levels will
peak a hair below 4 ft MLLW. Webcams show some overwash on Highway
87/124 on the Bolivar Peninsula and figure the other susceptible
roads along the Bolivar Peninsula, Blue Water Highway and Beach
Drive in Surfside are seeing similar issues. So, ongoing Beach
Hazard Statement will continue to address the above issues. Suspect
we`ll probably see some minor issues continue around times of high
tide for the next 24-36 hours then gradually improve as winds/seas
diminish.

Small Craft Advisories will continue today. Speeds should taper off
some later this morning, and we may be able to let the bays go by
late morning. But in the Gulf, elevated seas of 8-10ft will take a
while to subside. Gradual improvement is expected in the coming days
as the gradient relaxes and winds/seas diminish. Though uncertainty
exists (and remains worth keeping an eye on), winds will probably
back to more of an offshore direction this weekend as an area of low
pressure tracks from the Yucatan into the north central or
northeastern Gulf. 47

&&

.TROPICS...
NHC is highlighting a tropical disturbance in the southwest
Caribbean that has a 80 percent of tropical development over the
next 5 days. We will continue to monitor this disturbance as it
moves towards the Yucatan and southern Gulf. 47

&&

.AVIATION...
Patchy MVFR ceilings this morning should lift back into VFR
territory by mid-late morning. VFR conditions should persist for the
remainder of the day. Isolated showers should remain mostly confined
along/south of I-10. Even then, not expecting much of an aviation
impact. 47

&&

.CLIMATE...
The City of Houston established a new annual rainfall total yesterday.
So far in 2017, 74.18 inches of rain has been recorded. The old annual
rainfall record was 72.86 inches set in 1900. 42
&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 87 69 88 67 89 / 10 10 10 10 10
Houston (IAH) 87 70 88 68 89 / 20 10 10 10 10
Galveston (GLS) 87 78 88 77 87 / 20 10 10 10 10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...Small Craft Advisory until 10 AM CDT this morning for the
following zones: Galveston Bay...Matagorda Bay.

Small Craft Advisory until 7 PM CDT this evening for the
following zones: Coastal waters from Freeport to the
Matagorda Ship Channel out 20 NM...Coastal waters from High
Island to Freeport out 20 NM...Waters from Freeport to the
Matagorda Ship Channel from 20 to 60 NM...Waters from High
Island to Freeport from 20 to 60 NM.

&&

$$

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snowman65
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I just need it to be cool and dry in Nashville Oct 14-17, please. Whatever you have to do to make that happen....LOL :lol:
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DoctorMu
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Image

Forecast is on track. GFS and Euro swapped on strength...but indeed the west side of the storm will yield northerly winds, which ironically mean 100°F+ in August

...but potentially cool now with a front approaching.

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srainhoutx
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Some changes occurred overnight via the reliable track guidance suggesting a Westward shift due to the ECMWF and UKMET shifting into a Central/SE Louisiana landfall potential, but the impacts in SE Texas still appear to be minimal at this time other than some higher tides and a slight increase in our weekend rainfall outlook. For our Neighbors in Central Louisiana on Eastward along the Mississippi, Alabama and Florida Gulf Coast, it's time to monitor potential Nate a bit more closely. There remains a great deal of uncertainty in the intensity due to interaction with the approaching full latitude trough across the Central United States and how quickly soon to be Nate accelerates and re curves NE around the Western Periphery of the SE Ridge Saturday into Sunday as well as what disruption occurs with land interaction along its path across the NW Caribbean Sea. Our Cold front still looks to push through late on Monday into early Tuesday ushering in cooler and drier air in its wake.

Tropical Depression Sixteen Discussion Number 4
NWS National Hurricane Center Miami FL AL162017
500 AM EDT Thu Oct 05 2017

Deep convection associated with the depression has increased over
the eastern portion of the circulation overnight, however there
has only been a slight increase in overall banding. Subjective
Dvorak intensity estimates suggest that the depression is near
tropical-storm strength, but with the center located near the
western edge of the deep convection the cyclone is kept as
a 30-kt tropical depression for this advisory.

The intensity forecast remains quite uncertain due to expected land
interaction today, and possibly again in about 48 hours when the
system passes near the Yucatan peninsula. The depression could
still become a tropical storm before the center moves over
northeastern Nicaragua and eastern Honduras later today. After the
cyclone moves north of Honduras, it will traverse the warm waters of
the northwestern Caribbean Sea, where the upper-level environment is
also forecast to be conducive for strengthening. However, the amount
of strengthening is likely to depend on the structure of the inner
core after it crosses land. The intensity models have continued
their downward trend, but the NHC forecast remains near the higher
side of the guidance due to these favorable conditions and
persistence from the previous advisory. Some additional
strengthening is possible while the system moves over the southern
and central Gulf of Mexico, and the NHC intensity forecast brings
the system to hurricane strength within 72 hours. This is in best
agreement with the SHIPS intensity model.

The depression is moving northwestward or 315/6 kt. The cyclone is
forecast to move northwestward to north-northwestward during the
next day or two around the western side of a ridge the extends from
near the southeastern Bahamas southwestward into the central
Caribbean Sea. By the weekend, a large mid- to upper-level ridge is
forecast to build off the coast of the southeastern United States,
and this should steer the cyclone north-northwestward at a faster
forward speed. After 72 hours, the system is expected to recurve
around the northwestward side of the ridge. The track guidance is
in better agreement this cycle with the latest runs of the ECMWF
and UKMET models shifting westward, closer to the previous GFS and
HWRF iterations. This has required a fairly substantial westward
shift in the NHC forecast track at 72 h and beyond.


KEY MESSAGES:

1. The depression is forecast to strengthen and bring tropical storm
conditions to portions of Nicaragua and Honduras through early
Friday. Heavy rainfall could produce life-threatening flash
flooding and mud slides in portions of Nicaragua, Honduras, Costa
Rica, and Panama through Friday night.

2. The system could be near hurricane intensity when it approaches
the Yucatan Peninsula late Friday, bringing direct impacts from
wind, storm surge, and heavy rainfall, and a hurricane watch is
in effect for a portion of this area.

3. The system is forecast to strengthen over the Gulf of Mexico and
could affect portions of the northern Gulf Coast as a hurricane this
weekend, with direct impacts from wind, storm surge, and heavy
rainfall. However, it is too early to specify the timing, location,
or magnitude of these impacts. Residents along the Gulf Coast from
Louisiana through the Florida Panhandle should monitor the progress
of this system and heed any advice given by local officials.


FORECAST POSITIONS AND MAX WINDS

INIT 05/0900Z 13.3N 83.3W 30 KT 35 MPH
12H 05/1800Z 14.3N 83.9W 30 KT 35 MPH...INLAND
24H 06/0600Z 16.3N 84.8W 35 KT 40 MPH
36H 06/1800Z 19.0N 86.0W 45 KT 50 MPH
48H 07/0600Z 21.8N 87.4W 55 KT 65 MPH
72H 08/0600Z 27.8N 89.5W 65 KT 75 MPH
96H 09/0600Z 34.0N 86.5W 35 KT 40 MPH...INLAND
120H 10/0600Z 39.5N 79.0W 25 KT 30 MPH...POST-TROP/INLAND

$$
Forecaster Brown

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srainhoutx
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BULLETIN
Tropical Storm Nate Intermediate Advisory Number 4A
NWS National Hurricane Center Miami FL AL162017
800 AM EDT Thu Oct 05 2017

...TROPICAL DEPRESSION BECOMES TROPICAL STORM NATE NEAR THE
COAST OF NICARAGUA...
...FLOODING RAINS EXPECTED OVER PORTIONS OF CENTRAL AMERICA...



SUMMARY OF 800 AM EDT...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...13.9N 83.4W
ABOUT 10 MI...15 KM S OF PUERTO CABEZAS NICARAGUA
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 8 MPH...13 KM/H
MINIMUM CENTRAL PRESSURE...999 MB...29.50 INCHES


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

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
* Sandy Bay Sirpi Nicaragua to Punta Castilla Honduras

A Hurricane Watch is in effect for...
* Punta Herrero to Rio Lagartos Mexico

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

Interests elsewhere in Honduras, the Bay Islands, western Cuba and
the Yucatan Peninsula should monitor the progress of Nate.

For storm information specific to your area, please monitor
products issued by your national meteorological service.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 800 AM EDT (1200 UTC), the center of Tropical Storm Nate was
located near latitude 13.9 North, longitude 83.4 West. Nate is
moving toward the northwest near 8 mph (13 km/h), and this motion is
expected to continue this morning. A north-northwestward motion at
a faster forward speed is forecast to begin later today and continue
through Friday night. On the forecast track, the center of Nate
should move across northeastern Nicaragua and eastern Honduras today
and then over the northwestern Caribbean Sea tonight and Friday.
The center is expected to approach the coast of the Yucatan
peninsula late Friday.

Maximum sustained winds are near 40 mph (65 km/h) with higher
gusts. Little change in strength is expected today as the center
of Nate moves across northeastern Nicaragua and eastern Honduras.
Strengthening is likely over the northwestern Caribbean Sea tonight
and Friday.

Tropical-storm-force winds extend outward up to 60 miles (95 km)
mainly over water to the east of the center.

The estimated minimum central pressure is 999 mb (29.50 inches).
Puerto Cabezas recently reported a pressure of 1001 mb
(29.56 inches)


HAZARDS AFFECTING LAND
----------------------
RAINFALL: Nate is expected to produce the following rain
accumulations through Friday night:

Nicaragua...15 to 20 inches, isolated 30 inches
Costa Rica and Panama...5 to 10 inches, isolated 20 inches
Honduras and Belize...2 to 5 inches, isolated 8 inches
Eastern portions of the Yucatan peninsula...4 to 8 inches, isolated
12 inches

Heavy rainfall will occur over a wide area, including locations well
away from the center along the Pacific coast of Central America.
This rainfall could cause life-threatening flash floods and
mudslides.

WIND: Tropical storm conditions are expected within portions of the
warning area in Nicaragua and Honduras today and tonight. Tropical
storm and hurricane conditions are possible within the watch area in
Mexico beginning late Friday.

SURF: Swells generated by Nate are affecting portions of the coast
of Nicaragua, and will begin to affect other land areas around the
northwestern Caribbean later this week. These swells are likely to
cause life-threatening surf and rip current conditions. Please
consult products from your local weather office.


NEXT ADVISORY
-------------
Next complete advisory at 1100 AM EDT.

$$
Forecaster Beven
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tireman4
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000
FXUS64 KHGX 050912
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
412 AM CDT Thu Oct 5 2017

.DISCUSSION...
Drier air continues to edge into Southeast Texas from the east and
northeast, but will keep some low rain chances in the forecast for
parts of our southern areas where some higher moisture levels reside.
Above normal temperatures will persist until next week`s cold front
arrives. But before the front moves through our area and cools things
down back toward near normal October temperatures, we`ll be dealing
with Tropical Depression Sixteen that the National Hurricane Center
strengthens into Tropical Storm Nate as it moves out of the southwest
Caribbean Sea, into the Gulf of Mexico and toward the central or eastern
Gulf coast states over the weekend as a hurricane. Based on this track,
we`ll carry low rain chances over the weekend and adjust either upward
or downward over the next couple of days based on future NHC forecasts.
Will continue to have low rain chances in the forecast for Monday and
Tuesday ahead of the cold front that we`ll have moving through the
area and off the coast Monday night through Tuesday morning. Cooler
temperatures (especially overnight lows) can be expected for much of
the remainder of the week as north to northeast winds persist. 42
&&

.MARINE...
5-8ft/11sec east swell still moving thru the waters, but expect both
winds and seas to be on a gradual downward trend. Will go ahead and
extend the Beach Hazards Statement into Friday morning which will
cover the continued elevated water levels, surf, and rip currents.
Also extended the Small Craft Advsy thru 4 pm for the 20-60nm
offshore group to give the swell time to fall below 7 ft.

Trof situated near south Fl will trek wnw across the Gulf and bring
an increased chance of shra/tstms across the coastal waters Fri
night and Saturday as it moves into the nw Gulf. TD #16, situated
off the coast of Nicaragua, is forecast to strengthen and become TS
Nate and move northward and into the southern Gulf early Saturday.
Continued strengthening should continue and it is forecast to become
a hurricane before it makes landfall in the central or eastern Gulf
states late Sunday. We`ll keep an eye on a potential swell moving
into the upper Tx coastal waters Sunday

There`s some model differences in the extended, but have coordinated
with nearby offices and will continue to favor the ECMWF which
brings a cold front off the coast Monday night or Tuesday. May need
SCA`s in its wake. 47

&&

.AVIATION...
Other than a few areas of patchy fog and MVFR ceilings during the
early/mid morning hours, VFR conditions are expected for the
remainder of the period. 47

&&


.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 89 66 89 69 89 / 10 0 0 0 10
Houston (IAH) 89 67 87 69 88 / 10 10 10 10 20
Galveston (GLS) 88 77 88 76 87 / 20 10 10 10 20

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...Small Craft Advisory until 4 PM CDT this afternoon for the
following zones: Waters from Freeport to the Matagorda Ship
Channel from 20 to 60 NM...Waters from High Island to
Freeport from 20 to 60 NM.

&&

$$

42/47
sau27
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The last couple of GFS runs and now the 12z Euro have backed off on the front for next week. Up till today the Euro was pretty consistent with a Tuesday/Wednesday frontal passage, while the GFS has been less consistent- showing FROPA between Tuesday and Friday, showing a weaker backdoor front (including the last 2 runs), or no front until the week after next. I imageine it is this uncertainty that is contributing to Nate's track shifting further west. I dont think Nate will be out problem, but I would certainly like to get that front through here.
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Just like that....it's gone :(
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DoctorMu
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WTF????? GFS, Canadian, Euro, Ensemble have the front washing out over the Hill Country on Tuesday...yet Nate isn't strong :evil:

NOAA is hanging onto some cooling beginning Monday.


Edit: it appears that the front gets hung up in a swath of moisture lingering from Nate, instead of the other way around. Perhaps a shift East for Nate might help our cause.
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I see some folks a fretting over that cold front. While it may not be as strong as some anticipated, it still looks like the frontal boundary arrives Monday evening into early Tuesday ushering in cooler and drier air and NW breezes Tuesday afternoon into Wednesday. Nate appears to be moving NNW in the Gulf of Honduras this morning and should begin accelerating NNW today into tonight and throughout the day tomorrow before turning NNE prior to landfall somewhere near or just East of New Orleans on East toward Pensacola, Nate looks like a typical monsoonal gyre type storm where all the heaviest rainfall and wind are well to the East of the center of circulation and I expect that trend to continue (much like Cindy in June) right up to landfall. Minimal impacts expected West of the storm including here in SE Texas...unless something dramatically changes today into tonight.
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Friday morning briefing from Jeff:

Hurricane Watch is in effect for the US Gulf coast from Morgan City, LA to the MS/AL border

Tropical Storm Watch is in effect from Morgan City, LA to Intracoastal City, LA and from the MS/AL border to the AL/FL border

Storm surge watch is in effect from Morgan City, LA to the AL/FL border including Lake Pontchartrain.

Nate will accelerate across the NW Caribbean and Gulf today and Saturday and landfall on the US Gulf coast early Sunday

Mandatory evacuations are in effect for portions of SE LA outside of hurricane protection levees

Discussion:
The center of Nate has emerged over the waters of the western Caribbean Sea overnight and recent USAF mission indicates the surface pressure has fallen from around 1000mb to 995mb with surface winds mainly to the east of the center near 45mph. Nate is a tropical cyclone embedded within a large monsoon circulation over central America which is preventing the system from developing rapidly at the moment. A NOAA high altitude mission yesterday evening sampled the air mass surrounding Nate and found an extremely moist profile with deep tropical moisture extending up to the 300mb level. Additionally, a powerful low level jet axis will be developing within the southern flank of the monsoon circulation aimed at the SW Caribbean Sea and into the eastern flank of Nate over the next 24 hours which will help to begin to accelerate the system NNW.

Track:
The rapid acceleration of Nate toward the NNW has begun with the forward motion now up to 14mph. There has been some modest changes to the forecast track guidance in the last 24 hours with several models now showing Nate hooking a harder right or NE turn just before landfall over SE LA. Given the west to east direction of the US Gulf coast a deviation of the motion toward the NE prior to landfall could potentially alter the landfall point. Models also continue to indicate a very fast forward motion of 20-30mph over the Gulf of Mexico as Nate is swung NNW/N on the western flank of a building high off the FL east coast and on the NE side of a strong upper level low over the SC Gulf of Mexico and ahead of an approaching cold front over the central US. Nate should reach the NE Yucatan tonight and then then NC Gulf of Mexico on Saturday afternoon and landfall along the SE LA/MS/AL coast early Sunday morning.

Preparations to protect life and property must be completed today along the Gulf coast as conditions will rapidly deteriorate on Saturday.

Intensity:
Nate is in an overall favorable environment, but the competing forces from the larger monsoon circulation that Nate is within may help to mitigate rapid intensification. USAF mission this morning is not finding very strong winds near the center of Nate suggesting the inner core is weak at the moment, however systems over the western Caribbean Sea do not always need much time to develop and Nate could be near hurricane intensity as it approaches the Yucatan later today. Once in the Gulf of Mexico overall conditions appear to continue to favor intensification, with the exception of the increasing forward speed. Nate will become embedded within a very strong mid level SSE flow across the central Gulf of Mexico and while strong winds are likely across the eastern flank of the system, Nate’s fast forward motion may make it hard for convection and strong winds to wrap around the west side. This could help to throw off the balance needed near the inner core for any sort of rapid deepening in favor of more modest intensification.

NHC brings Nate to a 80mph cat 1 hurricane at the 48 hr forecast point, but Nate could continue to increase in intensity up to landfall around 50-54 hrs from now.

Impacts:

Storm Surge:
Storm surge flooding of 4-6 feet above the ground near the coast will be possible over SE LA including the N/W shores of Lake Pontchratrain eastward along the MS/AL coasts including Mobile Bay. Given the exact track over/near SE LA large portions of SE LA outside hurricane protection systems will be covered in sea water…in some cases to several feet deep.

Storm Surge Inundation Map:
http://www.nhc.noaa.gov/refresh/graphic ... n#contents

Winds:
Tropical storm force winds will arrive into SE LA early afternoon on Saturday and build to hurricane force Saturday night and spread inland over MS/AL/western FL panhandle. Core winds of Nate will landfall over SE LA early Sunday morning and then spread rapidly NE across much of MS/AL on Sunday and well into N GA/TN Sunday night. Large areas of power outages will be possible given that Nate’s wind field will move very far inland.

Rainfall:
Due to the rapid forward motion of Nate rainfall amounts of 5-8 inches will be possible along the track of the system with isolated totals up to 15 inches.

SE TX Impacts:
Moisture will be increasing on the NW flank of Nate across the NW Gulf of Mexico today and tonight. A few outer rain bands may approach the upper TX coastal waters tonight into Saturday and a few of these may move inland along the coast.

Winds will increase out of the ENE/NE into Saturday night with speeds on average of 10-15mph inland, 15-20mph along the coast, and 20-25mph across the waters.

Tides are already running 1-2 feet above normal and this will continue with ENE winds and larger swells moving into the coastal waters on Saturday. Could see values push near 3.0-3.5 feet on Saturday of total water which may cause minor overwash near Hwy 124/87 on Bolivar.
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DoctorMu
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GFS, Canadian, Ensemble models nudge the front and Nate farther east this morning. Nate is also projected to move faster ahead of the front. Hope this trend continues. Tuesday and Wednesday bring now slightly cooler and drier air. 70s highs are gone, though.
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tireman4
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Remember, we see this all the time. Models ( especially the GFS) will lose a cold front in a 5-7 day period before it arrives. The pro mets can tell you, models still have a hard time with cool/cold air and timing thereof. Just because it lost it or lessens the intensity does not mean it will not be a cool down. I have learned over my many years of following weather that trends are your friend.
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tireman4
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XUS64 KHGX 061830
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
130 PM CDT Fri Oct 6 2017

.AVIATION...
VFR. Few CU over the area with dry air draped over the area. Light
easterly winds should veer slightly by 10-30 degrees but still
light. Moist axis associated with the surface trough south of
Louisiana will shift westward and bring an increase in clouds
mainly MVFR CIGS near 12z Saturday to the GLS/IAH area along with
the threat of showers. By 15z Saturday expect SHRA and a few TSRA
along and east of the surface trough axis which should be near an
LBX/HOU/IAH line. Intermittent MVFR CIGS/VISBY 15z Saturday and
beyond with the axis going nearly stationary.
45
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snowman65
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Looking like we may just skip fall altogether and go straight into winter in December sometime...thank you, La Nina...lol.
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srainhoutx
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Saturday morning briefing from Jeff:

Hurricane racing toward the US Gulf coast

Preparations to protect life and property must be rushed to completion across SE LA, MS, AL, and the FL panhandle

Discussion:
Near continuous USAF missions into Nate overnight have revealed a lopsided hurricane with strong winds mainly confined to the eastern side of the circulation. Overall the satellite appearance is not one suggesting rapid intensification and the pressure has only fallen about 4mb since late yesterday evening. There is deep convection near/around the center, but Nate lack a well defined inner core or well defined eyewall which is likely helping to mitigate a more rapid pace of intensification. As Nate arrives on the US Gulf coast this evening the current wind pattern if it holds suggests area west of the center may see very little impact.

Track:
Nate is racing NNW at 22mph on the east side of a building mid level ridge east of FL and an upper level low over the southern Gulf of Mexico and ahead of an approaching deep layer trough over the central US. Nate may turn a little NW for a period today and then back NNW and N this evening. On this track the hurricane will approach and likely make landfall over SE LA (Mississippi River Delta) and then track NNE toward a second landfall on the MS coast. Nate will then accelerate inland over MS/AL Sunday.

Intensity:
Nate is gradually intensifying and while conditions in the Gulf of Mexico are favorable for intensification, the lack of a well defined inner core should preclude significant intensification prior to landfall. With that said, Nate still has 16-18 hours over a very warm Gulf of Mexico and a 90-100mph hurricane at landfall is certainly possible…high end cat 1 or low end cat 2. After landfall, Nate will begin to decay, but the fast forward motion will bring strong winds well inland over much of MS/AL/N GA and TN

Impacts:

Storm Surge:

Major storm surge flooding is likely along coastal MS and AL and into Mobile and Pensacola Bays.

Significant and life threatening storm surge flooding is likely over extreme SE LA and coastal MS/AL/NW FL panhandle. Storm surge values of 5-9 feet above normally dry ground near the coast will be possible over coastal MS and AL including Mobile Bay and the portions of SE LA outside of hurricane risk reduction systems (levees) S and E of the metro New Orleans area. Maximum storm surge values will be found near and just right of the landfall of the center which appears most likely along and east of the SW MS coast or east of the Gulfport, MS area. Water levels currently being forecast will overtop HWY 90 along the MS coast. Given the current forecast track, storm surge values into Lake Pontchratrain are not expected to reach levels of hurricane Issac in 2012.

http://www.nhc.noaa.gov/refresh/graphic ... n#contents

Winds:
Winds of 85-95mph will be possible near and east of the center landfall location especially across the lower MS River Delta and then into coastal MS and AL. Given the fair weak wind field on the western side of the system, winds across metro New Orleans may be significantly weaker than those along the MS coast, however any wobble of the center only a slight distance to the west would bring hurricane conditions to New Orleans.

Rainfall:
Rainfall amounts of 3-6 inches will be possible along the track of Nate as the fast forward motion will help to reduce overall totals.
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DoctorMu
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Nate is charging along at 27 mph - more like an east coast October hurricane. Lake Ponchatrain is susceptible to that east wind ahead of the center.


The cold front washes out tonight and Sunday and merges with Nate.

A second front moves our way on Tuesday.


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