Hail and Damaging Winds in Louisiana, January 2, 2017

Area Forecast Discussion
National Weather Service Shreveport LA
258 AM CST Mon Jan 2 2017

.DISCUSSION...
Strong convection already developing in an area of strong
isentropic lift just south of our region as well as across
portions of NW LA and into SW AR. VAD Wind Profiler from 88D
indicates that 5kft winds are approaching 40kts from the SSW.
Likely that the activity across SW AR and NW LA is elevated in
nature resulting in a hail threat given that the warm front as of
08z was located near a Tyler...Center...Natchitoches to Natchez
line. As the convection to our south lifts northward along with
the northward moving warm front...will need to monitor the
likelihood of this convection becoming more surface based with
time which would in turn result in a wind and/or isolated tornado
threat.

Otherwise...areas of dense fog continues to be a problem across
much of the Four State Region this morning. Current Dense Fog
Advisory runs through 6 AM this morning and thinking is that as
the warm front moves northward this morning...near or in the
vicinity of the I-20 corridor by 6 AM...the warm sector airmass
should have enough mixing associated with it that fog should mix
out as well. That might not be the case with the dense fog north
of the I-20 corridor across SE OK...the northern third of NE TX
into S AR so will need another update at 12z and will determine
what to do with the present Dense Fog Advisory at that time.

Otherwise...our big weather maker for the day in the form of a
vigorous upper level trough was located across the TX Hill Country
early this morning with developing convection from Junction City
and Stephenville to near Wichita Falls Texas and Lawton Oklahoma.
Short term progs are in good agreement with this upper trough
becoming more negatively tilted as it moves into Central Texas and
into the Middle Red River Valley of NE TX/SE OK and SW AR through
the late morning and early afternoon hours. The warm front by late
morning should be in the vicinity of the AR/LA border and this
will result in a severe weather threat across all but our extreme
northern zones throughout the day today. Large hail and damaging
thunderstorm wind gusts appear the main threat but backing of sfc
winds in the warm sector will also pose a tornado threat and
earlier discussion with the Storm Prediction Center suggests that
a Tornado Watch will become necessary later this morning to the
east of Severe Thunderstorm Watch #001 currently in effect just to
our west. The good news is that this trough is a very quick mover
with the intense convection expected to be east of our eastern
most zones by mid aftn as dry slotting quickly fills in behind the
convection.

Did not make too many significant changes to the extended package
given the serious concern to the short term but the big cool down
will commence late Tuesday and Tuesday Night in the form of a
strong cold front. This front is a little slower in the latest
short term progs compared to this time yesterday given its very
shallow nature initially but kept the post frontal airmass and
extended periods dry through Friday with perhaps some returning
moisture for next weekend resulting in the need for some small
pops. The ECMWF is much colder in the Wed through Fri timeframe
than the GFS and it does try to generate some precipitation late
Thu through Fri in association with a reinforcing shot of colder
air. Seeing that the ECMWF continues to struggle with any sort of
consistency with its precip generation with this second intrusion
of cold air by late week...will leave any winter precipitation
mention out for now.

Thanks for coordination this morning SPC and neighboring offices.
Prelims to follow...13.

&&

.PRELIMINARY POINT TEMPS/POPS...
SHV  72  50  73  44 / 100  10   0  10
MLU  73  52  75  46 / 100  10   0  10
DEQ  67  42  67  35 / 100  10  10  10
TXK  68  48  69  39 / 100  10   0  10
ELD  69  47  71  42 / 100  10   0  10
TYR  73  48  71  38 / 100  10   0  10
GGG  75  48  72  40 / 100  10   0  10
LFK  75  48  75  44 / 100  10   0  10

&&

.SHV WATCHES/WARNINGS/ADVISORIES...
AR...Dense Fog Advisory until 6 AM CST early this morning for ARZ050-
     051-059>061-070>073.

LA...Dense Fog Advisory until 6 AM CST early this morning for
     LAZ001>006-010>014-017>022.

OK...Dense Fog Advisory until 6 AM CST early this morning for OKZ077.

TX...Dense Fog Advisory until 6 AM CST early this morning for TXZ097-
     112-126-137-138-150-151-153-166-167.

&&

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HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SHREVEPORT LA
1100 AM CST SUN JAN 1 2017

ARZ050-051-059>061-070>073-LAZ001>006-010>014-017>022-OKZ077-
TXZ096-097-108>112-124>126-136>138-149>153-165>167-021700-
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-
1100 AM CST SUN JAN 1 2017

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...

VISIBILITIES WILL IMPROVE THROUGH THE DAY TODAY...WITH ISOLATED TO
SCATTERED SHOWERS POSSIBLE. SHOWERS AND ISOLATED THUNDERSTORMS
WILL INCREASE IN COVERAGE LATER THIS EVENING AND INTO THE
OVERNIGHT HOURS. AREAS OF DENSE FOG WILL LIKELY REDEVELOP AS WELL
ACROSS PORTIONS OF DEEP EAST TEXAS...NORTHWEST LOUISIANA...AND
SOUTHWEST ARKANSAS.

A STRONG UPPER LEVEL STORM SYSTEM WILL MOVE INTO THE TEXAS HILL
COUNTRY AFTER MIDNIGHT TONIGHT WITH STRONG TO SEVERE THUNDERSTORMS
LIKELY ACCOMPANYING THE STORM SYSTEM. THESE STORMS COULD MOVE
INTO THE SOUTHERN HALF OF NORTHEAST TEXAS NEAR OR JUST BEFORE 6 AM
MONDAY MORNING. THESE STORMS COULD PRODUCE STRONG AND DAMAGING
WIND GUSTS...ALONG WITH LARGE HAIL AND ISOLATED TORNADOES. THE
MORE SIGNIFICANT SEVERE WEATHER THREAT WILL LIKELY HOLD OFF UNTIL
JUST AFTER SUNRISE MONDAY MORNING.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY...

STRONG TO SEVERE THUNDERSTORMS WILL BECOME MORE WIDESPREAD ON
MONDAY...ENCOMPASSING MAINLY THE SOUTHERN HALF OF NORTHEAST TEXAS
AND NORTHERN LOUISIANA. THE STORMS WILL BE QUICK MOVERS WITH THE
WORST OF THE WEATHER EXPECTED TO BE EAST OF THE FOUR STATE REGION
BY MONDAY AFTERNOON. DAMAGING WIND GUSTS AND LARGE HAIL ARE THE
PRIMARY THREATS...BUT ISOLATED TORNADOES CERTAINLY CANNOT BE
RULED OUT. MUCH COLDER TEMPERATURES WILL BEGIN MOVING INTO THE
REGION LATE ON TUESDAY INTO TUESDAY NIGHT. AT THIS TIME...IT
APPEARS THAT MOSTLY DRY CONDITIONS WILL ACCOMPANY THIS COLDER
AIRMASS...AT LEAST UNTIL FRIDAY INTO SATURDAY WHEN SMALL CHANCES
FOR PRECIPITATION RETURN TO THE FORECAST.

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF EMERGENCY MANAGEMENT PERSONNEL...AMATEUR RADIO
OPERATORS...AND STORM SPOTTERS COULD BE NEEDED JUST PRIOR TO
SUNRISE MONDAY MORNING...BUT WILL MORE LIKELY BE NEEDED AFTER
SUNRISE ON MONDAY.

Special Weather Statement
National Weather Service Shreveport LA
224 AM CST MON JAN 2 2017

LAZ001>003-012-020915-
Bossier LA-Bienville LA-Caddo LA-Webster LA-
224 AM CST MON JAN 2 2017

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHERN WEBSTER...SOUTHEASTERN
CADDO...NORTHWESTERN BIENVILLE AND SOUTHEASTERN BOSSIER PARISHES
UNTIL 315 AM CST...

At 223 AM CST, Doppler radar was tracking a strong thunderstorm 13
miles east of Stonewall, or 16 miles south of Bossier City, moving
northeast at 35 mph.

Dime size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Minden, Haughton, Sibley, Doyline, Dubberly, Dixie Inn, Heflin,
Curtis, Caspiana, Taylortown, Lake Bistineau South, Elm Grove, Plum
Orchard Landing, Koran, Ninock, Gilark, Noles Landing, Lake Bistineau
North, Mc Dade and Ogden.

LAT...LON 3224 9348 3224 9361 3227 9361 3232 9366
      3232 9369 3272 9334 3260 9318 3259 9318
      3259 9316 3254 9310
TIME...MOT...LOC 0823Z 221DEG 29KT 3230 9358

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