-- Discussion containing changed information from previous version are highlighted. --
797
FXUS64 KLIX 182316 AAA
AFDLIX

Area Forecast Discussion...UPDATED
National Weather Service New Orleans LA
616 PM CDT Tue Jun 18 2024

...NEW AVIATION...

.SHORT TERM...
-- Changed Discussion --
(This evening through Wednesday night)
Issued at 354 PM CDT Tue Jun 18 2024

Current radar shows scattered showers across the CWA with a wide
swath of light to moderate rain west of the local area. These
showers are moving relatively quickly at around 20kts towards the
west due to strong onshore flow north of Potential Tropical Cyclone
One. This system is located northwest of the Yucatan Peninsula and
slowly drifting northwestward. While this storm system is not
forecast to directly affect the central Gulf Coast, continued
easterly moisture advection will mean scattered afternoon showers
will remain a risk through the evening hours. The CWA should see
rain ending earlier in coastal Mississippi than it will closer to
Baton Rouge due to drier air aloft moving in from the east. High
PWATs (near 95th percentile for this date) mean that any passing
showers will produce efficient rainfall rates of 2-3"/hr, though
rainfall totals from these will be around an inch or 2 due to the
forward motion. Once we lose diurnal heating this evening, should
see a quick dropoff in activity.

Another lower end impact from PTC One will be elevated winds. These
winds may be in excess of 20 mph in coastal areas because of the
strong nearly zonal pressure gradient, so coastal flooding will
continue to be a minor concern. The current coastal flood advisory
was expanded to include areas around the tidal lakes based on
current obs which show a 1 to 2 foot increase in lake levels today.
Have held off on a wind advisory for now but will possibly need one
for the southshore of Lake Pontchartrain at some point. Low
temperatures will remain above the climatological normal for mid
June due to the high moisture and remaining cloud cover.

A strengthening upper ridge, possibly reaching 600dm (that`s really
really high), centered over the Mid Atlantic will nose westward
through the southeastern CONUS into tomorrow. This will cause PTC
One to track west into northern Mexico, therefore removing some
moisture content in our CWA. This will reduce POPs going into
tomorrow, but because of how broad the system is and with PWATs at
an impressive, though reduced, 2" on average region wide,
scattered showers with efficient rainfall rates will remain in the
forecast, though these should also be quick moving. High
temperatures will begin to increase closer to normal tomorrow with
decreased rainfall and cloud coverage along with the ridge
starting to nudge into our CWA.
-- End Changed Discussion --


&&

.LONG TERM...
-- Changed Discussion --
(Thursday through Monday night)
Issued at 354 PM CDT Tue Jun 18 2024

Warmer and generally drier conditions expected as we end this week
and head into the weekend as the ridge continues to build west.
Subsidence from the ridge will continue decreasing POPs through the
weekend. Highs will reach the mid 90s by Friday, potentially upper
90s for inland areas this weekend. Heat indices will breach 100
degrees by Friday and 105 degrees by Sunday areawide. Heat
advisories may be needed if these trend a little higher. Afternoon
sea breeze showers will remain a possibility through this period,
primarily in coastal areas, which could bring temporary relief in
spots. There is a chance another tropical disturbance tries to
develop in the Bay of Campeche next week, though details are murky
and no disturbance has formed yet. We`ll keep an eye on it, though
nothing to worry about for now.
-- End Changed Discussion --


&&

.AVIATION...
-- Changed Discussion --
(00Z TAFS)
Issued at 616 PM CDT Tue Jun 18 2024

VFR conditions through the cycle. The convective chance/coverage
will decrease for Wednesday. Cannot rule out an isolated or
scattered thunderstorm or two for mainly the Louisiana terminals
generally along and west of I55. For these areas decided to use
PROB30s to highlight this concern. Otherwise, winds will increase
out of the southeast with some gusts exceeding 30 knots at
times...especially the coastal terminals. (Frye)
-- End Changed Discussion --

&&

.MARINE...
Issued at 354 PM CDT Tue Jun 18 2024

Elevated winds persist across the marine areas in response to PTC
One centered in the Bay of Campeche. Recent obs in the open Gulf
waters support a Gale warning, so one was issued. Hazardous
conditions are expected over much of the open waters for the next
several days, however, and Advisories may need to be extended
beyond the current expiration over some or most of the waters.

&&

.PRELIMINARY POINT TEMPS/POPS...
-- Changed Discussion --
MCB  71  88  71  91 /  10  30   0  10
BTR  76  91  76  94 /  10  40   0  30
ASD  76  89  75  91 /  10  50  20  50
MSY  81  89  80  89 /  10  60  20  60
GPT  76  89  76  91 /  30  50  30  40
PQL  75  92  74  93 /  30  40  20  30
-- End Changed Discussion --

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
LA...Small Craft Advisory until 10 AM CDT Thursday for LAZ068.

     Coastal Flood Advisory until 4 PM CDT Wednesday for LAZ058-060-
     066>070-076>078-080-082-084-086-087.

GM...Small Craft Advisory until 10 AM CDT Thursday for GMZ530-532-534-
     536-538-550-552-555-557-577.

     Gale Warning until 1 AM CDT Thursday for GMZ570-572-575.

     Small Craft Advisory from 1 AM to 10 AM CDT Thursday for GMZ570-
     572-575.

MS...Coastal Flood Advisory until 4 PM CDT Wednesday for MSZ086>088.

GM...Small Craft Advisory until 10 AM CDT Thursday for GMZ532-534-536-
     538-550-552-555-557-577.

     Gale Warning until 1 AM CDT Thursday for GMZ572-575.

     Small Craft Advisory from 1 AM to 10 AM CDT Thursday for GMZ572-
     575.
-- End Changed Discussion --

&&

$$

SHORT TERM...DS
LONG TERM....ME
AVIATION...RDF
MARINE...RW