886
FXUS64 KLIX 170451
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
1151 PM CDT Tue Jul 16 2024

...New AVIATION...

.SHORT TERM...
(This evening through Wednesday night)
Issued at 341 PM CDT Tue Jul 16 2024

Tonight through Thursday morning, expect a summertime pattern to
dominate. Scattered daily showers and storms will be possible,
especially during the afternoon and early evening hours. PoPs are
generally around 60%, but not expected to develop showers and
storms much until late afternoon hours. High temperatures will be
in the mid 90s with heat index values 108 to 112 degrees
forecast. The overnight lows will be right around 80 degrees for
much of the area again tonight, which will add to the heat stress
tomorrow. And that combined with the prolonged (multiple days now)
heat, will contribute to the heat stress and increase the impacts
felt by people. Consequently, we have issued a heat advisory for
tomorrow for our entire area except immediate coastal Louisiana
from 10am through 7pm CT. Additionally, in urban areas, it is
important to note that the heat will linger into the evening hours
longer than rural areas, so the heat stress will also linger a
bit longer than most places. People should take precautions to
stay hydrated and take frequent breaks when working outside! Rain
chances increase greatly Thursday and onward, so the heat concerns
should be much less.

&&

.LONG TERM...
(Thursday through Monday night)
Issued at 341 PM CDT Tue Jul 16 2024

The upper level low situated to our west will propagate only slowly
eastward due to the base of the trough over the Great Lakes being
too far north to bring it eastward more quickly. Models anticipate
the upper low to track over the northwestern Gulf, placing us in a
zone of enhanced divergence by Thursday. Combined with a surface
front moving southward and stalling near the coast alongside ample
moisture (2.1-2.3") and instability, rainfall coverage is
expected to increase by the end of the week. Lifting from the
front will be highest in the northern part of the CWA, and the WPC
has included regions north of SH-10 in a Marginal Risk for
excessive rainfall on Thursday as a result. The upper low will
weaken and trough out once south of our CWA, but an additional
shortwave impulse at 500 mb will serve as the "new" forcing aloft
by Friday and keep rain coverage elevated. Another shortwave will
cross into Texas later this weekend and provide lift along the
weakening stationary front, and with continued high moisture
supply and instability, expect POPs to remain high into the
weekend and early next week. Storm coverage will be maximized
during the afternoon hours when diurnal heating, and therefore
instability, is strongest.

The enhanced rainfall coverage will decrease high temperatures below
what we have seen and will see for the next 2 days, potentially into
the upper 80s by the weekend, though there will be little change in
overnight lows. The weak deep-layer flow through the entire
timeframe will mean storms will be slow-moving, elevating flood
concerns. As per usual with summertime convection, pinning down
exactly where storms will fire is a challenge, so estimating exact
rainfall totals is also challenging. 1-3 inches during the period
can be anticipated with locally higher amounts. The severe threat is
slim to none given the lack of vertical shearing during the period,
though waterspouts just offshore and over Lake Pontchartrain are
possible with some storms. Heavy rain and flash flooding will be the
primary concern regardless.

&&

.AVIATION...
(06Z TAFS)
Issued at 1150 PM CDT Tue Jul 16 2024

Convection should be a little more widespread tomorrow and have
continued vicinity groups with TEMPOs for gusty winds associated
with thunderstorms in the early to mid afternoon. Have not
included any vis restrictions, though they`ll certainly be
possible if/when any of the heavier storms move over the
terminals. With no strong forcing or focus for the storms
tomorrow, confidence in specific timing of any restrictions is
fairly low but future TAF updates may be able to narrow those
windows.

&&

.MARINE...
Issued at 341 PM CDT Tue Jul 16 2024

A benign weather pattern will be setting up over the area for the
next week. Southerly and moderate (10-15kts) will be in place for
the next week. Daily showers and storms will be possible with
lightning and brief, gusty winds (30-40mph), which could be a
hazard for mariners.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  74  93  74  90 /  30  60  20  90
BTR  79  96  78  95 /  20  70  20  90
ASD  78  94  78  93 /  20  70  20  90
MSY  79  93  79  92 /  20  80  20  90
GPT  79  92  78  91 /  10  50  30  90
PQL  77  95  77  94 /  10  50  30  90

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Heat Advisory from 10 AM to 7 PM CDT Wednesday for LAZ034>037-
     039-046>048-056>060-064-065-071-076>090.

GM...None.
MS...Heat Advisory from 10 AM to 7 PM CDT Wednesday for MSZ068>071-
     077-083>088.

GM...None.
&&

$$

SHORT TERM...MSW
LONG TERM....MSW
AVIATION...LN
MARINE...MSW