River Flood Warning 43, NWS New Orleans, LA

Area Forecast Discussion
National Weather Service New Orleans LA
305 PM CDT Fri Aug 26 2022

.SHORT TERM...
Tonight through Sunday...
The boundary will lift tonight, and there will not be as much of a
focus for rainfall that develops. Southerly surface winds will
help to enhance warm air and moisture advection into the area,
which will enhance instability over the area. PW values will
remain high over the weekend hovering around 1.8 to 2 inches,
which is above the 75th percentile for the SPC sounding
climatology. Consequently, any rainfall that occurs will be
efficient and have higher rainfall rates. Looking at the models,
it will be "drier" over the weekend, but rainfall is still
expected daily over the next few days thanks to the abundant
moisture and instability. It just may not be quite as widespread,
looking at model consensus. PoPs are still hovering in the 60-70%
range during the afternoon hours Saturday and Sunday. They were
adjusted down some to account for the higher bias NBM has compared
to the general consensus, but the environment is still conducive
for locally heavy rainfall inside of stronger storms. Some gusty
winds and frequent lightning will also be possible inside of
stronger storms, but not likely. Overall, another rainy weekend,
but with the chance of having some drier periods mixed in. MSW

.LONG TERM...
Monday through Thursday...
Zonal flow will dominate the upper level pattern next week.
Southerly surface winds will enhance warm air and moisture
advection into the area, enhancing instability. Some weak upper
level divergence will help to enhance lifting, mainly during the
daytime hours toward the end of the week. PW values are hovering
around 2-2.2 inches in the models, which is above the 90th
percentile for the SPC sounding climatology. So efficient rainfall
with higher rainfall rates will be expected next week inside of
stronger storms. Looking at the models, rainfall chances will be
enhanced all week with showers and storms possible daily,
especially during the afternoon hours. Due to the abundant
moisture and instability, locally heavy rainfall will be possible
daily next week. The good news is that we are not seeing
indications of any widespread flooding events. Mainly, stronger
storms could produce isolated flash flooding, especially in
vulnerable areas or areas that have already received a lot of
antecedent rainfall. A strong storm or two may have the potential
to produce gusty, subsevere winds and frequent lightning, but that
would also be a more isolated occurrence. Overall, another rainy
week next week is expected with the potential for locally heavy
rainfall inside of stronger storms. MSW

&&

.AVIATION...
18Z TAF Package...
VFR conditions prevail at most area airports. BTR is experiencing
MVFR conditions due to surrounding thunderstorms. TEMPO groups
with MVFR conditions are forecast at all area airports this
afternoon due to showers and storms moving through the area.
Conditions will return to VFR by late this evening at most area
airports and persist through the rest of the forecast period. MCB
and BTR will experience LIFR conditions around daybreak briefly
due to fog conditions causing lower ceilings. MSW

&&

.MARINE...
Winds will be southerly to easterly and moderate (<15 knots)
tonight through Wednesday. Thursday through Friday, winds will be
northerly to easterly and moderate (<15 knots). Wave heights will
correspond to the wind speeds. MSW

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  70  85  70  87 /  40  80  40  70
BTR  74  89  74  90 /  40  80  40  80
ASD  73  89  73  90 /  50  80  40  70
MSY  75  87  76  88 /  40  80  40  70
GPT  74  87  75  88 /  40  70  40  60
PQL  72  87  73  88 /  50  70  40  60

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Flood Watch until 7 PM CDT this evening for LAZ035>037-039-048-
     071-076-079>084.

GM...None.
MS...Flood Watch until 7 PM CDT this evening for MSZ068>071-077-
     080>082.

GM...None.
&&