Area Forecast Discussion
Issued by NWS Shreveport, LA
FXUS64 KSHV 270843
Area Forecast Discussion
National Weather Service Shreveport LA
243 AM CST Mon Feb 27 2017
Showers and thunderstorms pushing east across northeast Texas,
southern Arkansas, and extreme north Louisiana at this time due to
enhanced low-level warm advection in the vicinity of a warm front.
As the morning progresses, convection to develop south of
Interstate 20, becoming more widespread through mid to late
morning before diminishing slightly through the early afternoon. A
somewhat enhanced pressure gradient between a surface high in the
Atlantic and a low in the Great Plains to allow for south winds
around 10 to 15 mph today. High temperatures this afternoon to
range from around 70 near De Queen to near 80 in Lufkin. Chance of
showers and thunderstorms persisting overnight with lows in the
Severe thunderstorms possible on Tuesday evening into Wednesday
morning across the entire ArkLaTex with an enhanced threat
focused mainly north of Interstate 20. Ingredients supporting
severe weather threat are a moist unstable airmass, an approaching
upper-level trough, a strong low-level jet, and an approaching
surface cold front to focus convection. However, despite these
several ingredients supporting the possibility of severe weather,
other inhibiting factors somewhat complicate the forecast.
First, warm sector diurnally driven storm development may be
limited by the lack of a surface focus. Second, clouds will
likely limit the heating necessary to initiate convection. Thus,
it appears that severe weather threat will be confined to
approaching frontal boundary late in the evening in conjunction
with 500 mb height falls. Damaging winds and hail will be the
biggest threat with isolated tornadoes possible due to strong
shear just ahead of frontal boundary where southerly flow
interacts with eastern migration of front.
Severe weather threat pushes east on Wednesday morning as squall
line develops along front and spreads east across southern
Arkansas and north Louisiana. Front should exit the region by
midday Wednesday with high pressure building in its wake.
Temperatures behind the front to range from highs in the 60s to
lows in the 40s though Saturday. Surface high to shift east of the
region on Saturday evening bringing a return flow of gulf moisture
and increased chances for showers and thunderstorms for Sunday.
.PREV DISCUSSION... /issued 1159 PM CST Sun Feb 26 2017/
For the 27/06Z TAFs, MVFR conditions overtaking most terminals to
begin this period as ceilings lower in locations with showers and
thunderstorms. Thunder is still best handled with TEMPO conditions
but could become better organized on through Monday morning as an
upper level disturbance shifts eastward across TX into our region.
Ceilings will likely continue to deteriorate with mostly MVFR and
occasional IFR conditions possible through much of Monday morning
as convection increases and expands farther east into the region.
Convection should begin to wane during Monday afternoon with just
isolated activity still possible through the end of the TAF cycle.
Otherwise, mainly sely winds between 5-10 kts to prevail with some
occasional higher gusts invof on convection.
.PRELIMINARY POINT TEMPS/POPS...
SHV 76 65 82 65 / 60 30 30 30
MLU 75 65 83 67 / 70 30 30 30
DEQ 69 58 76 56 / 40 30 40 60
TXK 71 62 78 60 / 50 30 40 50
ELD 72 62 80 63 / 50 30 40 40
TYR 77 64 80 59 / 60 20 40 50
GGG 77 65 81 62 / 50 20 40 40
LFK 80 66 83 65 / 60 20 30 30