Hurricane Warning 1016, NWS New Orleans, LA

Area Forecast Discussion
National Weather Service New Orleans LA
505 AM CDT Fri Oct 6 2017

.DISCUSSION...Main focus is on Tropical Storm Nate. We should have
one more day of rather quiet weather but look for rain to begin to
move in early Saturday with conditions quickly deteriorating
Saturday evening through Sunday morning.

Tropical Storm Nate moved back into the water over the western
Caribbean Sea shortly after midnight and has actually strengthened
slightly. No changes in the latest forecast from NHC. Models are in
very good agreement in the forecast track of Nate. Nate will
continue to move to the northwest and pick up forward speed as it
moves around the western side of the ridge over FL and the
southeastern CONUS. By Saturday a strong s/w will move through the
mid MS Valley and help break down the western periphery of the ridge
and this will lead to Nate turning more north late Saturday and then
north-northeast overnight Saturday and Sunday as it moves over
extreme southeast LA and coastal MS. Nate will quickly lift
northeast into AL during the day Sunday and conditions should
improve after midday Sunday.

As for intensity that is the bigger issue. Still quite a bit of
uncertainty with respect to intensity forecast. Multiple things
suggest Nate should continue to intensify and possibly all the way
to landfall. What should be light shear, very warm water, and
eventually a nice outflow channel to the north could lead to some
decent intensification. However the global models (GFS and EC)
both keep a relatively weaker Nate. It appears they both keep Nate
from being a stacked system and therefore can never really get
organized. This may be due to interaction with the Yucatan. NHC
has kept the forecast of a 70 knot hurricane at landfall.

Hurricane and storm surge watches were hoisted last night and no
changes have been made since then. Warnings will likely be needed
later this morning as we move into the 36 hour window. Other
issue we need to keep an eye on is flash flooding. Very rich
tropical moisture will push into the area with Nate. With that we
will see very efficient rain especially on the east side of this
storm. Don't be surprised to see areas along and west of 55 not
see that much in the way of rain while locations along coastal MS
could see in excess of 5 inches mainly late Saturday afternoon
through midday Sunday. Holding off on a flash flood watch right
now as this is still 4 periods out and minor shifts in the track
could make it hard to pinpoint where the heaviest rain will occur.

After Nate look for rather quiet weather. One not so cool feature is
that the cold front doesn't look as strong as previously thought
however we should see a slight cool down and drier air by Tuesday as
the front moves through. /CAB/

&&

.AVIATION... No significant weather impacts to aviation expected
through this evening. Persistent east winds of 5 to 10 knots and VFR
conditions can be expected through the period. There could be some
light shra across the southern terminals late today.

&&

.MARINE...
Moderate easterly flow to maintain higher than normal tide levels
and seas through tonight. Depending on the intensification trends of
Tropical Storm Nate entering the gulf Saturday, packet swells may
emanate into the north gulf preceding Nate that could reach the
coastal waters by Saturday afternoon before winds and waves really
increase during the overnight hours heading into Sunday morning.
Tropical storm and hurricane force winds are expected to spread over
the outer waters after 21z Saturday and continuing through around 18Z
Sunday before lowering later in the day Sunday from west to east.

&&

.DECISION SUPPORT...
DSS code: Orange.
Deployed: None.
Activation: None.
Activities: Hurricane and Storm Surge Watches

Decision Support Services (DSS) Code Legend
Green  = No weather impacts that require action.
Blue   = Long-fused watch, warning, or advisory in effect or
         high visibility event.
Yellow = Heightened impacts with short-fused watch, warning or
         advisory issuances; radar support.
Orange = High Impacts; Slight to Moderate risk severe; nearby tropical
         events; HazMat or other large episodes.
Red    = Full engagement for Moderate risk of severe and/or
         direct tropical threats; Events of National Significance.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  87  71  84  73 /   0  10  60  50
BTR  89  73  86  74 /  10  20  60  60
ASD  87  75  85  75 /  10  30  70  70
MSY  84  76  84  77 /  20  30  70  70
GPT  86  76  83  76 /  20  30  70  70
PQL  87  74  84  74 /  20  30  70  70

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Hurricane Watch for LAZ039-040-049-050-056>072.

GM...Hurricane Watch for GMZ530-532-534-536-538-550-552-555-557-570-
     572-575-577.

MS...Hurricane Watch for MSZ077-080>082.

GM...Hurricane Watch for GMZ532-534-536-538-550-552-555-557-570-572-
     575-577.

&&

CAB

Hazardous Weather Outlook
National Weather Service New Orleans LA
553 AM CDT Fri Oct 6 2017

GMZ530-532-534-536-538-550-552-555-557-570-572-575-577-LAZ034>037-
039-040-046>050-056>072-MSZ068>071-077-080>082-062300-
Lake Pontchartrain and Lake Maurepas-Mississippi Sound-
Lake Borgne-Chandeleur Sound-Breton Sound-
Coastal Waters from Port Fourchon LA to Lower Atchafalaya River
LA out 20 nm-
Coastal waters from the Southwest Pass of the Mississippi River
to Port Fourchon Louisiana out 20 NM-
Coastal Waters from Boothville LA to Southwest Pass of the
Mississippi River out 20 nm-
Coastal waters from Pascagoula Mississippi to Stake Island out
20 NM-
Coastal waters from Port Fourchon Louisiana to Lower Atchafalaya
River LA from 20 to 60 NM-
Coastal waters from Southwest Pass of the Mississippi River to
Port Fourchon Louisiana from 20 to 60 NM-
Coastal Waters from Stake Island LA to Southwest Pass of the
Mississippi River from 20 to 60 nm-
Coastal waters from Pascagoula Mississippi to Stake Island
Louisiana out 20 to 60 NM-Pointe Coupee-West Feliciana-
East Feliciana-St. Helena-Washington-St. Tammany-Iberville-
West Baton Rouge-East Baton Rouge-Ascension-Livingston-Assumption-
St. James-St. John The Baptist-Upper Lafourche-St. Charles-
Upper Jefferson-Orleans-Upper Plaquemines-Upper St. Bernard-
Upper Terrebonne-Lower Terrebonne-Lower Lafourche-Lower Jefferson-
Lower Plaquemines-Lower St. Bernard-Northern Tangipahoa-
Southern Tangipahoa-Wilkinson-Amite-Pike-Walthall-Pearl River-
Hancock-Harrison-Jackson-
553 AM CDT Fri Oct 6 2017

This Hazardous Weather Outlook is for portions of Southeast
Louisiana...South Mississippi and the adjacent coastal waters.

.DAY ONE...Today and Tonight

A Hurricane Watch is in effect for coastal Mississippi and much
of southeast Louisiana as well as a Storm Surge Watch for coastal
areas through Sunday. Warnings will likely be issued later today.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

A Hurricane Watch is in effect for coastal Mississippi and much
of southeast Louisiana as well as a Storm Surge Watch for coastal
areas through Sunday. Tropical Storm Nate is forecast to move
into the Gulf of Mexico by Saturday and then strengthen to a
category 1 hurricane as it approaches the central Gulf Coast
region late Saturday night and early Sunday.

Heavy rain is also possible as Nate moves across the region.
Widespread 3 to 5 inches with locally higher amounts are
anticipated. Heaviest rain will occur on the east side of Nate and
a flash flood watch may be needed for Saturday night and Sunday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be requested over the weekend.

CAB