Area Forecast Discussion Issued by NWS Shreveport, LA
000
FXUS64 KSHV 241156
AFDSHV
Area Forecast Discussion
National Weather Service Shreveport LA
656 AM CDT Tue May 24 2022
.AVIATION...
For the 24/12Z TAF period, IFR/LIFR cigs cover our airspace with
some patchy areas of fog. Expect these IFR/LIFR cigs to persist
through much of this morning in addition to some patchy drizzle or
light rain. This will occur as a warm front lifts northward from
the coast back into our region this morning through the afternoon.
Meanwhile, an upper level disturbance will be shifting into the
region with convection at most terminals, especially during the
afternoon. Some improvement in cigs is expected but generally no
better than MVFR/low VFR through the afternoon and evening with
increasing convection expected again overnight along a cold front.
E/NE winds will be veering more S/SE as the warm front lifts back
across the region with speeds increasing to 10-15 kts with higher
gusts near 20-25 kts and stronger during periods of convection.
/19/
&&
.PREV DISCUSSION... /issued 440 AM CDT Tue May 24 2022/
SHORT TERM.../Today through Wednesday/
Despite a quiet start early this morning, a very active short-term
period is expected over the next 36 hours. This includes potential
severe weather and flooding across the region in what has become a
rather complex forecast scenario.
First, let`s begin with the warm front to our south that continues
to lag in its northward retreat thus far. However, expect that to
change over the next several hours with rapid warm air advection
spreading into our entire region from mid to late morning through
early afternoon. Warm fropa will likely result in some scattered
showers and isolated thunderstorms this morning, then followed by
additional stronger convection with a potent shortwave lifting NE
from south Texas through this afternoon. Pockets of heavy rainfall
will be possible with this disturbance, which will arrive in the
warm sector air following the warm front. Thus, expect PWATs to
increase throughout the day to between 1.5-2 inches in addition to
the warmer temperatures and dew points with instability increasing
in the broadening warm sector throughout the afternoon and evening
hours. A few strong storms will be possible with this initial wave
of convection today, but the severe threat will increase late this
evening and overnight as an evolving MCS continues to gather steam
over NW Texas this morning. This MCS is expected to closely track
along the middle Red River Valley with a trailing cold front down
across the I-35 corridor of north and central Texas as we approach
midnight.
With additional destabilization expected later this evening after
a brief window of recovery time following the initial convection,
we will reload for what should be a much more significant round
of convection and severe weather. As the cold front shifts east of
I-35, expect the line of thunderstorms to rapidly accelerate
eastward with bowing segments likely embedded within the line.
Given increasing shear values in the 0-1km and 0-3km layers along
with SRH over 200 m2/s2 ahead of the front, the threat of some
embedded tornadoes will be possible in addition to the greater
threat of damaging wind gusts. Large hail will also be possible
within storms along the line and moreso with any individual storms
preceding the line as mid-level lapse rates increase to between
7-8C/km. Finally, the threat we have been discussing for days now
is heavy rainfall and potential flooding with widespread rainfall
amounts of 2-4 inches possible through this event which will carry
into Wednesday before finally beginning to exit the region later
in the week as the cold front and upper trough shift east. With
that said, the Flash Flood Watch has been expanded to include our
entire region through 7AM Thu.
/19/
LONG TERM.../Wednesday Night through Monday Night/
By Wednesday evening, the aforementioned closed upper trough will
continue its eastward push through the Southern Plains, driving a
cool front through the area. The front will likely bisect the region
at this time, with ongoing showers and thunderstorms along and east
of it. This convection should end from west the east near daybreak
Thursday morning, but models are trending a little more southward
with the closed upper trough. This could result in some wrap around
light precip on Thursday across our SE Oklahoma and SW Arkansas
zones, along with areas along and north of the Interstate 20
corridor in East Texas and North Louisiana.
The closed upper trough will eject NE into the Mid South Region and
eventually into the lower Midwest Region by Friday morning. Dry
northwest flow will move into the region, which should result in
mostly sunny skies. By Saturday, northwest flow shift out of the
region as upper ridging builds into the Southern Plains and Lower
Mississippi Valley. This will keep dry and mostly sunny conditions
across the region through the first of next week.
Showers and thunderstorms, along with the post frontal airmass, will
keep below normal temperatures across the region on Thursday.
Afternoon temps will struggle to reach 80 degrees in most locations,
with some areas in our northern zones only climbing into the mid
70s. Below normal temps will continue into Friday morning, with lows
generally in the mid to upper 50s. However, a warming trend is
expected going forward into next weekend. Temperatures on Friday
afternoon and Saturday will be close to climatic normals. With upper
ridging in place, above normal temperatures will return by Sunday
into the first of next week, as afternoon highs will climb into the
lower 90s.
/20/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 83 67 78 60 / 80 70 90 40
MLU 84 69 81 63 / 80 50 100 80
DEQ 77 63 75 54 / 80 90 60 20
TXK 79 66 76 58 / 80 90 80 30
ELD 81 64 76 58 / 80 70 90 50
TYR 80 65 75 57 / 70 90 70 10
GGG 81 65 75 57 / 70 80 80 20
LFK 83 66 77 59 / 70 70 90 40
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...Flood Watch through Thursday morning for ARZ050-051-059>061-
070>073.
LA...Flood Watch through Thursday morning for LAZ001>006-010>014-
017>022.
OK...Flood Watch through Thursday morning for OKZ077.
TX...Flood Watch through Thursday morning for TXZ096-097-108>112-
124>126-136>138-149>153-165>167.
&&
$$
19/20