Drought in Louisiana, August 1 to 31, 2023

Area Forecast Discussion
National Weather Service New Orleans LA
1143 PM CDT Mon Jul 31 2023

...New AVIATION...

.SHORT TERM...
(This evening through Wednesday night)
Issued at 243 PM CDT Mon Jul 31 2023

A very persistent pattern will be in place through Wednesday
night, and this will result in continued excessive heat across the
region. This pattern will be dominated by a strong 500mb ridge
centered over Texas and extending eastward into the Lower
Mississippi Valley. Deep layer subsidence will keep the mid and
upper levels warm and dry through the period, and high temperatures
will continue to run well above average in the upper 90s and
lower 100s. Overnight lows will be near to slightly above average
as drier air in the mid-levels mixes down to the surface each
afternoon. Despite the somewhat lower humidity in place, heat
index readings will easily climb to between 110 and 115 degrees
each day, and excessive heat products are in effect for both
Tuesday and Wednesday.

The influence of the upper level ridge over the area will also
keep overall rain chances lower than average through the short
term period. PoP will peak in the late afternoon hours at 20 to 30
percent each day. The most likely areas for convective development
will be along and south of I-10 in close proximity to the
seabreeze and lakebreeze boundaries. Model sounding analysis
supports the potential for strong wind gusts with any deeper
convective cells that form as drier air is entrained into the
updraft cores. DCAPE in excess of 1000 J/KG is supportive of this
higher wet microburst potential. Any wind events will tend to be
isolated as overall convective coverage will be limited.

&&

.LONG TERM...
(Thursday through Sunday night)
Issued at 243 PM CDT Mon Jul 31 2023

Initially, the pattern will be the same as seen in the short term
for both Thursday and Friday. A strong 500mb ridge axis will
continue to drive the forecast, and this will keep both
excessively hot high temperatures near 100 degrees and lower than
average rain chances in place through the end of the workweek. A
pool of dry air in the mid-levels will continue to pose a risk of
entraining into deeper convective updrafts, and ultimately produce
some locally strong wind gusts. This is supported by continued
DCAPE values in excess of 1000 J/KG.

A slight change in the pattern is anticipated by the weekend as
the 500mb ridge axis over the area weakens. 500mb temperatures
will cool and moisture will increase aloft as subsidence
decreases. The combination of these factors will support greater
overall instability, and expect to see a return to more typical
PoP of 30 to 40 percent by Sunday. Temperatures will slowly modify
with the increase in convection and decrease in subsidence, but
will remain above normal in the mid to upper 90s for both
Saturday and Sunday. The increased humidity will also keep heat
index readings near 110 degrees, and fully expect to see either
heat advisory or excessive heat warning products in effect through
the weekend.

&&

.AVIATION...
(06Z TAFS)
Issued at 1140 PM CDT Mon Jul 31 2023

VFR conditions expected to prevail through the period under
continued influence of high pressure. Isolated convection expected
Tuesday afternoon, and have included PROB30 groups at BTR and the
south shore terminals where latest CAM guidance suggests
probabilities are a little higher.

&&

.MARINE...
Issued at 243 PM CDT Mon Jul 31 2023

A rather typical Summer pattern driven by the seabreeze cycle in
the lakes, sounds, and nearshore waters, and a prevailing
southerly flow on the northwestern periphery of a surface ridge
centered over the east-central Gulf of Mexico will be in place
through the end of the week. Winds will remain near or slightly
below 10 knots, and seas of 1 to 2 feet can be expected over
average. However, locally higher winds and waves will be possible
with any thunderstorm activity that forms each day.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  75  99  75 100 /   0  10  10  20
BTR  79 101  80 101 /  10  20  10  20
ASD  79 101  78 101 /   0  10  10  20
MSY  82  99  82  99 /   0  20  10  30
GPT  79  98  79  97 /   0  10  10  20
PQL  76  99  77  98 /   0  10  10  20

&&

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

     Excessive Heat Watch from Wednesday morning through Wednesday
     evening for LAZ034>037-039-046>048-056>060-064>071-076>090.

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

     Excessive Heat Watch from Wednesday morning through Wednesday
     evening for MSZ068>071-077-083>088.

GM...None.
&&

SHORT TERM...PG
LONG TERM....PG
AVIATION...DM
MARINE...PG