Special Weather Statement, NWS Shreveport, LA

Area Forecast Discussion
National Weather Service Shreveport LA
305 PM CDT Sat Aug 14 2021

.SHORT TERM.../Tonight through Sunday Night/

Isolated to scattered showers and thunderstorms continue to develop
this afternoon near remnant outflow boundaries in our southern and
eastern zones, generally south of Interstate 20 and east of
Interstate 49. Some additional development will be possible
through the remainder of the afternoon with peak heating along
and near other remnant outflow boundaries, but most of the
activity should diminish near sunset. Can't rule out some
overnight activity, but that convection should be isolated in
coverage. Rain chances will remain on tomorrow as an upper trough
continues to slowly shift southward into the region. Like today,
the greatest convection coverage will occur during peak heating
hours likely along other remnant outflow boundaries. Not expecting
any widespread severe weather, but locally heavy rainfall along
with brief gusty winds and frequent lightning will remain possible
in the stronger storms. One bonus with the activity is that we
will keep milder afternoon temperatures across the region, with
highs ranging from the mid 80s to lower 90s. /20/

.LONG TERM.../Monday through Saturday/

As we begin the extended forecast, the first of next week is
characterized by a broad area of low pressure in the form of a
longwave trough across the Great Lakes, into the Central and
Southern Plains with a tropical remnant(Fred)just off the FL/AL
Coast and upper ridging noted where it pretty much has been all
summer, across the western CONUS. A persistent upper level ridge
just off the Eastern Seaboard will tend to block the Upper Midwest
trough, even as Fred is forecast to get picked up by this trough
well east of our region. Given the position of the trough however,
much of our region should continue to experience widely scattered to
scattered, mainly diurnally driven convection each day through at
least Wednesday when it appears the trough will finally begin slowly
moving eastward towards the Ohio and Tenn Valleys.

Upper ridging begins to take the place of the upper trough across
the Southern Plains for Thu into Fri which should result in less
convection and an uptick in temperatures as will be shown with this
forecast.

It may be noted that while Fred should remain east of our region
early next week, Grace is forecast to follow close on Fred's heels,
forecast to move into the Bahamas by the middle of next week and
perhaps in the eastern and/or central Gulf of Mexico by late next
week into next weekend. The strength of the lead trough to our east
and the upper ridge to our west will ultimately decide Grace's
progression through the Gulf and this will of course will be
monitored closely with future forecasts.

13

&&

.PREV DISCUSSION... /issued 106 PM CDT Sat Aug 14 2021/

AVIATION...

A mix bag of flight conditions expected during the period.
Scattered convection is currently developing across the region, but
only affecting KMLU. VFR conditions are prevailing across the
remainder of the region, but more convection could lower flight
conditions this afternoon at the remainder of the sites. This
activity should diminish by sunset, but low cigs are possible near
near daybreak Sunday. Additional convection will be possible
towards the end of the TAF period. /20/

&&

.PRELIMINARY POINT TEMPS/POPS...
SHV  75  90  74  92 /  40  50  30  40
MLU  74  90  72  90 /  30  50  30  50
DEQ  71  88  69  90 /  30  40  20  20
TXK  73  89  72  90 /  30  40  20  20
ELD  71  87  69  89 /  30  50  20  30
TYR  74  88  73  91 /  40  50  30  30
GGG  73  88  72  90 /  40  50  30  30
LFK  74  91  72  92 /  30  50  30  40

&&

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

20/13

Hazardous Weather Outlook
National Weather Service Shreveport LA
631 AM CDT Sat Aug 14 2021

ARZ050-051-059>061-070>073-LAZ001>006-010>014-017>022-OKZ077-
TXZ096-097-108>112-124>126-136>138-149>153-165>167-151145-
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Union-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-
Red River-Bienville-Jackson-Ouachita-Sabine-Natchitoches-Winn-
Grant-Caldwell-La Salle-McCurtain-Bowie-Franklin-Titus-Camp-
Morris-Cass-Wood-Upshur-Marion-Smith-Gregg-Harrison-Cherokee-Rusk-
Panola-Nacogdoches-Shelby-Angelina-San Augustine-
631 AM CDT Sat Aug 14 2021

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

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

Slightly milder temperatures are expected today as an upper level
trough shifts south, and a weak frontal boundary slowly advances
toward the region. Showers and thunderstorms will become more
numerous this afternoon through early evening as daytime heating
will help to enhance any thunderstorms that develop. Gusty winds,
frequent lightning, and brief heavy rainfall may accompany some of
the stronger storms.

.DAYS TWO THROUGH SEVEN...Sunday through Friday...

As the frontal boundary enters our region, it is expected to stall
out late this weekend and help to maintain scattered thunderstorms
through much of next week before slowly lifting back to the north.
This will allow for hot temperatures to return by mid to late week
with only isolated thunderstorms still possible during afternoon
peak heating hours.

.SPOTTER INFORMATION STATEMENT...

Activation of emergency management personnel...amateur radio
operators...and storm spotters is not anticipated at this time.

19

Special Weather Statement
National Weather Service Shreveport LA
321 PM CDT Sat Aug 14 2021

TXZ152-153-166-142100-
Nacogdoches TX-San Augustine TX-Shelby TX-
321 PM CDT Sat Aug 14 2021

...A strong thunderstorm will impact portions of northeastern
Nacogdoches, western Shelby and northwestern San Augustine Counties
through 400 PM CDT...

At 321 PM CDT, Doppler radar was tracking a strong thunderstorm 9
miles southwest of Center. This storm was nearly stationary.

HAZARD...Winds in excess of 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Center, San Augustine, Timpson, Melrose, Martinsville, Arcadia,
Jericho and Stockman.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional
information and possible warnings from the National Weather Service.

&&

LAT...LON 3193 9440 3190 9422 3149 9411 3156 9455
TIME...MOT...LOC 2021Z 356DEG 1KT 3174 9432

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

15

Special Weather Statement
National Weather Service Shreveport LA
328 PM CDT Sat Aug 14 2021

TXZ136-142115-
Smith TX-
328 PM CDT Sat Aug 14 2021

...A strong thunderstorm will impact portions of southern Smith
County through 415 PM CDT...

At 328 PM CDT, Doppler radar was tracking a strong thunderstorm near
Tyler. This storm was nearly stationary.

HAZARD...Wind gusts up to 50 mph. A 49 mph wind gust was measured at
         Tyler Pounds Field with these storms at 316 PM.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Tyler, Whitehouse, Noonday and New Chapel Hill.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3240 9510 3219 9512 3224 9548 3225 9547
      3226 9547 3230 9545 3231 9546 3236 9545
      3237 9547 3239 9550 3242 9551 3243 9554
      3245 9555
TIME...MOT...LOC 2028Z 286DEG 4KT 3234 9535

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

15