Area Forecast Discussion Issued by NWS Little Rock, AR
000
FXUS64 KLZK 221944
AFDLZK
Area Forecast Discussion
National Weather Service Little Rock AR
244 PM CDT Fri Mar 22 2024
...New SHORT TERM, LONG TERM...
.SHORT TERM...
(This evening through Sunday)
Issued at 243 PM CDT Fri Mar 22 2024
A shortwave was located over Arkansas this afternoon, with a center
of circulation present on sat imagery across SE Arkansas. At the
surface, a slow-moving cold front was stretched across the state
from SW-NE, roughly from north of DEQ, to near CXW, to near JBR.
Cold front is a relative term, as of this moment temps were actually
warmer behind the front than south of it, as overcast conditions
prevailed along with light to moderate shower activity.
The front will push through the state tonight, and the shortwave
will exit to the east, bringing clearing skies and drier air. A flat
ridge will build in from the west.
Looking ahead, a broad trof will be taking shape across the western
US this weekend, and will start to push east. Cyclogenesis is
expected to spin up a surface low over eastern Colorado, and winds
over Arkansas will swing around to the south during the day. With
the system approaching and moisture levels increasing at the low
levels, some rain chances will start to creep back into the western
portions of the forecast area late Sunday night.
&&
.LONG TERM...
(Sunday Night through next Friday)
Issued at 243 PM CDT Fri Mar 22 2024
A lead shortwave trough ejecting from mean upper troughing over the
Wrn CONUS will move across the Plains/Midwest on Mon with a deep sfc
cyclone initially positioned across Wrn KS translating NEwrd to the
Great Lakes area by Mon evening. As this occurs, an attendant cold
front/dryline will begin sweeping Ewrd with modest thermal and
moisture advection occurring across the pre-frontal warm sector.
Latest guidance maintains a somewhat slower progression with this
system, indicating the potential for somewhat better poleward
moisture return and a related increase in instability across AR,
although confidence in this remains low attm. What remains more
apparent are the impressive dynamics progged to overspread the warm
sector on Mon with guidance showing 150+ kts of flow within a
strong, divergent upper jet and 40 to 50 kts of flow within the low-
level jet. Deep-layer shear will be equally impressive with 60 to 70
kts anticipated.
As with previous fcst cycles, however, significant concerns remain
regarding the quality of moisture and degree of destabilization.
Fcst dewpoint temps may reach the low 60s F over much of Srn AR and
perhaps into central/Ern AR, but it still appears the best fetch of
deep moisture will remain limited to Srn/SErn sections and farther S
into LA/MS. This may yield up to around 500 J/kg of MUCAPE over Srn
AR with some window for CINH erosion during the afternoon hours.
Otherwise, the ample dynamic forcing in place will need to overcome
poor thermodynamics in order to force strong/severe convection,
suggesting convection will only be maximized along/near the front as
it accelerates thru the state from the W on Mon.
Will maintain a conditional severe threat with this package,
primarily for Srn/SErn AR collocated with the best instability,
although the high-shear-low-CAPE nature of this system suggests a
non-zero severe wind threat elsewhere. This will be especially true
if momentum transfer is effective in bringing fast tropospheric flow
to the sfc, although low-level static stability could negate this to
a large degree.
Additionally, PWAT values up to around 1.5 inches will be conducive
for heavy rain, and despite the progressive nature of this front,
will readily support a broad area of 1 to 2 inch totals (locally
higher, especially over the SErn half of the state). Some flooding
will be possible where the heaviest QPF is realized.
Rain and thunder will gradually taper off W to E thru the day Tues
as the front departs and a drier air mass moves in from the NW. Sfc
ridging will prevail for the remainder of the period, although some
precip may work into the area as broad anticyclonic flow funnels
moisture into portions of SWrn/Wrn AR later in the week. Temps will
run slightly below average before moderating back to above average
as upper ridging builds in by the end of the week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Batesville AR 41 61 39 63 / 10 0 0 0
Camden AR 45 64 41 66 / 30 0 0 0
Harrison AR 36 60 40 61 / 30 0 0 10
Hot Springs AR 44 64 42 65 / 10 0 0 10
Little Rock AR 46 64 42 66 / 20 0 0 0
Monticello AR 46 62 42 66 / 50 0 0 0
Mount Ida AR 43 66 42 65 / 10 0 0 10
Mountain Home AR 37 61 38 62 / 10 0 0 0
Newport AR 42 59 39 63 / 10 0 0 0
Pine Bluff AR 45 61 41 64 / 30 0 0 0
Russellville AR 42 65 41 65 / 0 0 0 10
Searcy AR 42 61 38 64 / 10 0 0 0
Stuttgart AR 45 59 41 63 / 30 0 0 0
&&
.LZK WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...53
LONG TERM....69