830
FXUS64 KSHV 022350
AFDSHV

Area Forecast Discussion
National Weather Service Shreveport LA
650 PM CDT Thu May 2 2024

...New AVIATION...

.SHORT TERM...
(This evening through Friday Night)
Issued at 313 PM CDT Thu May 2 2024

A few scattered showers will continue to move northeast across
portions of Northern/Northeast Louisiana and Southwest Arkansas
through early this evening in the wake of the departing shortwave
trough that brought this morning`s MCS to the area. Additional
scattered convection may develop this evening along and north of
Interstate 20 along a remnant outflow boundary from the
aforementioned convective complex. The forecast becomes
increasingly uncertain during the overnight hours. For the last
couple of days, model guidance has generally been in decent
agreement that another convective complex will form across Texas
and Southern Oklahoma before diving east-southeast and into our
CWA early Friday morning, in a very similar situation to what we
had today.

The latest models introduce considerable uncertainty regarding
rain chances for Friday. The 12z NAM continues to be far more
aggressive than the remainder of the guidance. The GFS and ECMWF
also depict convection moving east-southeast into the area but
have trended downward regarding coverage, intensity, and QPF
amounts. Meanwhile, the vast majority of the CAMs depict very
little in the way of thunderstorms. Some of them either keep the
next MCS to our west and southwest, or don`t even show one
developing. The NSSL-WRF is the most supportive of another
convective complex, but has it quickly weakening with eastward
extent into the ArkLaTex by 09z-12z. Most of the guidance tends to
struggle in this type of pattern with a persistent southwest flow
and a surface boundary well to our northwest. The trends in the
CAMs are likely due to today`s convection overturning the
environment and lack of recovery of diurnal instability. However,
with low-level southerly flow and warm air advection some surface-
based CAPE could still recover tonight. If a convective complex
does develop to our west, the key factor in its survival into our
CWA will likely center around something that can help propagate
the complex eastward like a mature cold pool or the development of
a MCV. Unfortunately, as mentioned, model guidance struggles
greatly in these scenarios.

Based on the trends in the models, rain chances were lowered
somewhat after midnight tonight through much of Friday. This also
lowers forecast QPF amounts a great deal, as most locations are
generally expected to see an inch or less of additional rainfall
through Friday evening. Since the heavy rain threat has already
diminished for today, the Flood Watch was cancelled early. The
surface front that the next round of thunderstorms is expected to
develop along should stall near or north of I-30 Friday morning
before lifting back northward during the day. As a result, PoPs
should diminish Friday afternoon and become increasingly confined
to areas north of I-20 before falling below mentionable levels in
most areas by midnight Saturday morning.

CN

&&

.LONG TERM...
(Saturday through next Wednesday)
Issued at 313 PM CDT Thu May 2 2024

Saturday is likely to be a very similar situation to today and
Friday. Another weak disturbance in the southwesterly flow aloft
will trigger thunderstorms along the frontal boundary across the
Plains well to our north late Friday. What`s left of this complex
is expected to move into our area during the day Friday.
Redevelopment along a residual outflow boundary Saturday afternoon
should bring scattered showers and thunderstorms to much of the
northwest half of the CWA. The front should sag farther south
Saturday with yet another round of strong convection developing
along the front and dryline over Texas and Oklahoma. This batch of
storms should initiate farther south and should have a better
chance of reach our CWA during the day Sunday. In addition, the
shortwave trough moving across the Southern Plains appears to be
more defined than previous days, which should result in increase
lift helping to sustain the showers and thunderstorms. Thus,
widespread high PoPs in the forecast for Sunday, especially in the
morning.

Daily chances for showers and thunderstorms in the forecast
through at least Monday and Tuesday. The biggest change early next
week is that a much stronger longwave trough is forecast to lift
from the Southern/Central Rockies and into the Northern Plains.
This should keep the best large scale forcing well to our north
Monday and Tuesday. However, with strong low-level southerly flow
and southwesterly flow aloft, there will be plenty of instability
to fuel more convective development especially as a front finally
begins to move into and across the area on Thursday.

Rain chances are currently expected to be lower than in the short-
term forecast period and more scattered in nature. Combined with
strong southerly winds and warm air advection, perhaps the bigger
story will be the building heat and humidity next week. Daytime
high temperatures should be warming into the 90s in several
locations by Tuesday and may be into the mid 90s in many locations
by Wednesday and Thursday. Very humid conditions are also
expected. This will likely push peak heat index values near or
over the century mark across much of the area south of I-20.

CN

&&

.AVIATION...
(00Z TAFS)
Issued at 632 PM CDT Thu May 2 2024

A very complicated TAF forecast is anticipated over the next
24-hours, as uncertainties remain regarding overnight
precipitation. In the event a line of thunderstorms moves into the
region, TSRA will likely become much more widespread in FM groups.
Regardless, look for IFR and LIFR VIS and CIGS as low clouds
return by 03/10z, with SHRA/-RA following shortly thereafter.

/44/

&&

.PRELIMINARY POINT TEMPS/POPS...
SHV  69  81  68  86 /  50  50  20  40
MLU  68  81  65  86 /  40  60  30  30
DEQ  65  81  64  82 /  50  40  20  50
TXK  67  81  66  83 /  50  50  30  50
ELD  66  80  63  84 /  40  60  30  30
TYR  67  82  68  84 /  50  40  20  40
GGG  68  81  67  84 /  50  50  20  40
LFK  68  81  68  84 /  50  60  10  30

&&

.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&

$$

SHORT TERM...09
LONG TERM....09
AVIATION...44