137
FXUS64 KSHV 060514
AFDSHV

Area Forecast Discussion
National Weather Service Shreveport LA
1214 AM CDT Mon May 6 2024

...New AVIATION...

.UPDATE...
Issued at 1040 PM CDT Sun May 5 2024

No update is needed to the afternoon forecast package at this
time.

/44/

&&

.SHORT TERM...
(This evening through Monday Night)
Issued at 155 PM CDT Sun May 5 2024

The decaying thunderstorm complex moving from west to the east
across the Four State Region this morning temporarily stabilized
the airmass across a majority of the coverage area and there is
currently little in the way of convection (although showers and
storms continue to our north, east, and south). There still is a
good chance that at least isolated showers and storms will get
going later this afternoon through early this evening as the
atmosphere continues to recover and destabilize with temperatures
getting into the upper 70s and lower 80s. At least a few strong
storms producing small hail, frequent lightning, brief gusty
winds, and heavy downpours will be possible given marginal wind
shear and respectable instability, but the potential for severe
thunderstorms remains low / marginal.

Convection should dwindle later this evening due to the lack of
synoptic lift and fading instability, leaving a warmer than
average and somewhat muggy night. Lows should generally be in the
lower to mid 60s with low clouds and patchy fog building very late
tonight and then breaking up several hours after sunrise tomorrow
morning. Widespread dense fog is not very likely given the setup
and latest short term model guidance.

The southern edge of a vigorous upper level disturbance is still
expected to pass through the Southern Plains and Middle MS Valley
tomorrow, likely sparking an outbreak of severe thunderstorms to
the NW of our region late tomorrow afternoon into tomorrow
evening. The influx of additional deep Gulf moisture on building
southerly flow tomorrow afternoon should promote isolated to
scattered showers and thunderstorms in our coverage area, although
the ingredients for severe thunderstorm production will be much
less than will be the case to our NW. That said, strong storms
will be possible and a stray severe storm cannot be ruled out in
any areas. The Storm Prediction Center has a Slight Risk of
severe thunderstorm extending into locations NW of the I-30
corridor and this is mainly to cover the potential for severe
storms along and north of the Red River congealing into a squall
line that could effect those areas tomorrow night. All severe
weather hazards will be possible with that potential squall line
in those areas, but it is important to emphasize the potential for
significant severe weather is definitely concentrated to the NW
and west of those areas. Otherwise, expect high temperatures
tomorrow in the lower to mid 80s with lows tomorrow night in the
upper 60s to lower 70s. /50/

&&

.LONG TERM...
(Tuesday through next Saturday)
Issued at 155 PM CDT Sun May 5 2024

The main concern in the long range period of the forecast (Tuesday
into next weekend) is the potential for severe storms and heavy
rainfall, mainly Wednesday afternoon and Wednesday night - and
again Thursday afternoon and Thursday night. Also of some concern
is oppressive (for the time of year) heat Tuesday through
Thursday. During this latter period, many locations at least along
and south of I-20 will likely have temperatures peak in the range
of 90 to 93 degrees with peak heat index values pushing the
triple digits at least briefly. This kind of heat is very typical
of the summer, but could be hazardous for some folks given our
bodies will not yet have had a chance yet to acclimatize.

As alluded to above, the heat will be building on Tuesday and will
contribute to moderate to high atmospheric instability. The Storm
Prediction Center is advertising at least some risk of severe
storms north of I-20 on Tuesday due to the outside potential for
vigorous convection to fire up on a boundary lingering from the
Monday night convection. However, NWP and blended model guidance
is less than bullish about thunderstorm chances in these areas
those days and the official forecast has rain chances only ranging
from 10 to 20 percent. We will have to continue to monitor trends
for Tuesday, but at this point the larger threat from storms
looks to come Wednesday afternoon through Thursday night. On those
days, a series of disturbances coming through in fast westerlies
aloft gradually should push a cold front south through the area
over the course of 24 to 36 hours. The synoptic lift from these
disturbances, plus lift from the front, should promote the
development of strong to severe thunderstorms in an environment of
at least moderate instability and wind shear. One to three inches
of rainfall (with isolated higher amounts) will be possible in at
least central and northern zones over this period. Given the
saturated nature of the ground, this sort of rainfall possible in
a short time period could cause flooding issues.

Once the front clears the area to the south by early Friday,
confidence in the weather remaining quiet for more than a few days
is not great. While the passage of the front should bring
temperatures back to slightly below or near normal, there are
hints at another large incoming disturbance to potentially bring
thunderstorms back into the forecast before the coming weekend is
totally done. There are some NWP discrepancies this far out in the
forecast, but the early next week time period will be something to
watch. /50/

&&

.AVIATION...
(06Z TAFS)
Issued at 1211 AM CDT Mon May 6 2024

VFR conditions currently prevailing but expect a mix of MVFR/IFR
ceilings to develop across our airspace during the predawn hours
with those ceilings gradually giving way to low VFR ceilings by
late morning into the afternoon hours. Also kept VCTS during the
afternoon and early evening hours across most terminals given the
diurnally driven convective coverage expected today. Look for
stronger SSE winds today, especially across our western terminal
locations with sustained winds near 10-12kts with gusts upwards of
20kts expected at the TYR terminal.

13

&&

.PRELIMINARY POINT TEMPS/POPS...
SHV  74  89  74  91 /  10  10  10  20
MLU  71  89  72  91 /  10  10   0  10
DEQ  67  84  67  85 /  50  10  20  40
TXK  71  88  71  90 /  30  10  20  40
ELD  68  88  69  90 /  20  10  10  20
TYR  72  87  72  88 /  10   0  10  20
GGG  72  88  72  90 /  10   0  10  20
LFK  72  90  72  92 /   0   0   0  10

&&

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

$$

SHORT TERM...44
LONG TERM....44
AVIATION...13