Flash Flood Warning 40, NWS Shreveport, LA

Area Forecast Discussion
National Weather Service Shreveport LA
423 AM CDT Tue Jul 16 2019

.SHORT TERM.../Today through Wednesday/

Persistent clusters of thunderstorms continue across portions of
Southeast Oklahoma and Southwest Arkansas early this morning.
While the remnants of Barry have into southern Missouri, an area
of lift associated with a lobe of vorticity and associated PVA has
rotated south and east along the backside of the the disturbance
which is enhancing lift across the Ouachitas. This in association
with an axis of PWATs in excess of 2 inches along the I-30
Corridor is helping to sustain this activity. Doppler radar
rainfall estimates thus far across portions of Southwest Arkansas
are beginning to exceed 5 inches since about 11pm last night but
there has been a slow but steady push of this convection to the
east since midnight. Flash Flood Watches and Warnings are
currently in effect for this area and while trends over the last
hour has been for this activity to shift slowly eastward, high res
solutions suggest we may see some backbuilding of this convection
further upstream so for this reason, will leave the Flash Flood
Watch as is and allow the dayshift to trim the western portions of
the watch back if necessary.

Mesoanalysis showing another area of higher PWAT across Northeast
and East Central Louisiana this morning and this will be another
favored area for scattered convection which will likely not
materialize until we see sufficient diurnal heating. Did not stray
too far from MOS concerning temperatures today but did lower
readings just a few degrees across SW AR where rain should help to
hold temps in check. Further south along and south of the I-20
Corridor, temps and dewpoints will allow for maximum Heat Index
Values this afternoon to come close to Heat Advisory criteria but
for now, will hold off on an Advisory with this package.

For Wednesday, in the wake of the remnants of Barry will be a
developing ridge of high pressure aloft which should be centered
across Eastern Oklahoma and Western Arkansas. Likewise, upper
ridging will also be centered across the Northern Gulf Coast with
a weak shear axis noted between these two ridges. Cannot rule out
some isolated, diurnally driven convection Wed aftn across our
southern third but otherwise, we should see a dry Wednesday with
warm temperatures. Will likely see another afternoon of Heat
Indices approaching Heat Advisory criteria with a Heat Advisory
possibly becoming necessary for at least a portion of our region.

Thanks for the coordination this morning WPC,FWD and LZK. Prelims
to follow...13.

.LONG TERM.../Thursday through Tuesday/

The Bermuda upper ridge will hold sway over the Gulf of Mexico and
mid South into the weekend in the wake of the mid week short wave.
Our low level moisture will still remain somewhat high, which will
limit how hot the air temperature can get for now, but not so well
on the Heat Index which will be marginal. Air will warm into the
lower to mid 90s. Combined with the high humidity, heat index values
may be very close to Heat Advisory criteria once again, but only for
a short time if necessary.

Little in the way of rain will be expected Thursday and Friday, but
the sea breeze will get to work mainly South of I-20 initially over
the weekend. Then an approaching cold front will boost the output
with a late July passage early in the new work week. Look for a
1025mb high to be in place over NB/KN/OK and will continue to push
the front across the entire region by Tuesday morning or afternoon
if you like GFS or ECMWF respectively. The added clouds and rain
will help to cool temperatures much during this time frame.

/24/

PREV DISCUSSION... /issued 1142 PM CDT Mon Jul 15 2019/

AVIATION...

Spiral band of convection beginning to fire off across extreme se
OK and spreading east into sw AR, along and just north of a Broken
Bow to DeQueen line. Expecting a stnry but expanding east to west
line of very heavy rain. Eventually this line may affect the ktxk
terminal location prior to daybreak, and spread to the keld
terminal area by around 16/14-16z. Remainder of areal terminals
should remain rain free thru most of the mrng with only possible
low coverage in aftn with daytime heating and possible swd movg
outflow boundaries. Increasing south winds may bring period of
mvfr cigs to kmlu, kshv, and klfk. As remnants of Barry continue
to drift nwd, threat of concentrated convection from spiral bands
should be diminished with mostly skc and vfr conditions expected
after 17/00z areawide.

/07/

&&

.PRELIMINARY POINT TEMPS/POPS...
SHV  92  77  94  76 /  30  20  10   0
MLU  91  76  93  75 /  60  20  10  10
DEQ  87  73  93  74 /  60  30  10   0
TXK  87  76  93  75 /  50  30  10   0
ELD  85  74  93  75 /  80  40  10   0
TYR  93  77  94  76 /  20  10  10   0
GGG  93  77  94  75 /  20  10  10   0
LFK  92  75  94  76 /  20  20  20   0

&&

.SHV WATCHES/WARNINGS/ADVISORIES...
AR...Flash Flood Watch through this evening for ARZ050-051-059>061-
     070>073.

LA...None.
OK...Flash Flood Watch through this evening for OKZ077.

TX...Flash Flood Watch through this evening for TXZ097.

&&

13/24/07

Hazardous Weather Outlook
National Weather Service Shreveport LA
540 AM CDT Mon Jul 15 2019

ARZ073-LAZ006-014-020>022-161200-
Union-Ouachita-Grant-Caldwell-La Salle-
540 AM CDT Mon Jul 15 2019

This Hazardous Weather Outlook is for portions of south central
Arkansas and north central Louisiana.

.DAY ONE...Today and Tonight...

A Flash Flood Watch remains in effect through 4 pm this afternoon.
As the remnants of Barry continue to move northward into Arkansas,
additional heavy rain bands, well south of the center of
circulation, could develop and move into portions of the region
through this afternoon. If these bands materialize, rainfall
amounts of one to two inches will be possible which could result
in flash flooding of low lying and poor drainage areas.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday...

No hazardous weather is anticipated at this time.

.SPOTTER INFORMATION STATEMENT...

Activation of emergency management personnel, amateur radio
operators, and storm spotters may be needed through this afternoon
for the possibility of flooding.

ARZ050-051-059>061-070>072-LAZ001>005-010>013-017>019-OKZ077-
TXZ096-097-108>112-124>126-136>138-149>153-165>167-161200-
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-
Red River-Bienville-Jackson-Sabine-Natchitoches-Winn-McCurtain-
Bowie-Franklin-Titus-Camp-Morris-Cass-Wood-Upshur-Marion-Smith-
Gregg-Harrison-Cherokee-Rusk-Panola-Nacogdoches-Shelby-Angelina-
San Augustine-
540 AM CDT Mon Jul 15 2019

This Hazardous Weather Outlook is for portions of southwest
Arkansas, north central Louisiana, northwest Louisiana, southeast
Oklahoma, east Texas and northeast Texas.

.DAY ONE...Today and Tonight...

As the remnants of Barry continue to move northward into Arkansas,
additional heavy rain bands, well south of the center of
circulation, could develop late tonight across the northern third
of Northeast Texas, Southeast Oklahoma and Southwest Arkansas. If
these bands materialize, heavy rainfall will be the result, some
of which could result in flash flooding of low lying and poor
drainage areas. A Flash Flood Watch may become necessary for
these areas if forecast confidence increases.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday...

No hazardous weather is anticipated at this time.

.SPOTTER INFORMATION STATEMENT...

Activation of emergency management personnel, amateur radio
operators, and storm spotters may be needed through tonight for
the possibility of flooding.

13