210
FXUS64 KLUB 161910
AFDLUB

Area Forecast Discussion
National Weather Service Lubbock TX
210 PM CDT Sun Jun 16 2024

...New SHORT TERM, LONG TERM...

.SHORT TERM...
(This evening through Monday)
Issued at 210 PM CDT Sun Jun 16 2024

A much quieter evening and overnight are in the offing following
last night`s impressive heat burst south of Lubbock. Anticyclonic
flow has since overspread the area within a shortwave ridge that
lingers overnight. In spite of this ridging, strong heating and deep
mixing along a developing dryline in far eastern NM could be enough
to breach a healthy EML by peak heating. However, weak steering flow
and a narrow W-E axis of lower CIN should keep any storms confined
to near the TX-NM border. Addressed this poor coverage and
conditional precip scenario with a 10% PoP until 10 PM.

Southerly winds will remain quite breezy tonight and on Monday as
lee cyclogenesis holds steady across eastern CO under stronger
southwest flow. Tonight`s shortwave ridge will have departed by
daybreak ahead of modest height falls and weakly cyclonic SW flow.
This pattern looks more supportive for isolated storms late Monday
afternoon near a dryline setting up along the TX-NM border. The main
caveat is we`ll have a stronger cap tomorrow running about 1C warmer
than today at 700 mb. Considering highs tomorrow should eclipse
today`s temps and that most CAMs depict CIN eroding to near zero
along the dryline by peak heating, NBM`s silent PoPs were traded for
a sliver of 20s across our far western zones. Limited background
forcing should keep storms very spotty with enough directional shear
supportive of supercells - likely high based given deep and dry sub-
cloud layers.

&&

.LONG TERM...
(Monday night through next Saturday)
Issued at 210 PM CDT Sun Jun 16 2024

At the beginning of the period, isolated to perhaps widely-scattered
thunderstorms may be ongoing across portions of the western South
Plains. In the mid/upper-levels, an amplifying, positively-tilted
trough will encompass the western U.S. interior with the primary
shortwave trough digging into the northern Great Basin where a
cyclonically-curved, 250 mb jet streak near 100 kt rounds its base.
Farther south, coupling of another, more-zonal 250 mb jet streak
branching over the Desert Southwest and northern Mexico will nosing
into western Texas, resulting in a corridor of difluent flow aloft
as a shortwave perturbation ejects overhead after 18/00Z. At the
surface, backed, southeasterly flow is expected to be present as a
984-986 mb cyclone in eastern Colorado drives an isallobaric
response across the dry and moist sectors, with the dryline stalled
near the TX/NM state line. Minimal MLCINH, confluent flow, and
localized areas of convergence in vicinity of the dryline should
result in the formation of a few multi-cellular thunderstorms. The
presence of the cross-boundary shear vectors and moderately long
hodographs aloft will favor supercell wind profiles for right-moving
storms. Inverted-V profiles and LCLs rooted near 700 mb will result
in the potential for localized wind-damage, with gusts in excess of
60 mph expected with multi-cells that merge and transition into a
supercell or two. Warm-cloud depths approaching 13 kft AGL should
temper the risk for severe-caliber hail, and torrential rainfall
will accompany organized storms given the high volume of adiabatic
liquid water content beneath the freezing level. Localized flooding
may occur due to the slow storm motion at around 10-15 kt for cells
that achieve discrete propagation. The potential for thunderstorms
will wane after dark as surface-based inflow trajectories become
undercut from diabatic stabilization/increasing MLCINH. Slight
chance PoPs (10-15 percent) have been maintained for all locations
along and west of the I-27/HWY-87 corridors through tomorrow night
as the spatiotemporal coverage of cells should be limited due to
weak, large-scale forcing for ascent aloft.

Breezy, muggy, and warm conditions will prevail area-wide heading
into the morning hours Tuesday as the lee cyclone rotates towards
western Kansas beneath the amplified troughing aloft. Low stratus
fields may develop as the backed, low-level jet strengthens to near
30-35 kt amidst and a clear sky (less any residual anvil debris)
causes the boundary-layer to reach its saturation point. Advection
fog is not expected to form, however. Hot, dry, and breezy
conditions continue to be forecast for Tuesday as the airmass
remains capped beneath the slight increase in geopotential heights
as the northern-stream shortwave trough ejects into southern
Manitoba and the subtropical ridge over the eastern U.S. expands
with latitude. The orientation of these features will maintain the
broadly cyclonic flow over the region, with the coupling of the 250
mb jet streaks upstream of the CWA beginning to phase and eject
northeastward into the central Great Plains by Wednesday. Southerly
flow will be intact on Wednesday; however, it is forecast to dampen
in magnitude to around 10-15 mph as cessation of lee cyclogenesis
occurs to the north of the CWA. It is counterintuitive to have
cooler temperatures forecast beneath slightly positive geopotential
height tendencies, but this is the case for Wednesday as 850 mb
temperatures cool via adiabatic expansion from the easterly fetch
along the northern periphery of a tropical disturbance moving
northwestward out of the Gulf of Mexico. To the north of the CWA, a
cold front is forecast to stall in the vicinity of the OK/TX PH
region, and further progression to the south should be retarded by
the presence of the barotropic airmass eclipsing the CWA. Presence
of this stalling front to the north may lead to the first of
potentially multiple rounds of showers and thunderstorms for the
latter half of the forecast period, with low PoPs expanding across
the CWA heading into Thursday morning. The best potential appears to
be across the extreme southwestern TX PH nearest the stalled front
as moist, isentropic ascent increases amidst the near-easterly flow
at the surface-to-mid-levels.

The forecast becomes particularly complex by Thursday/D5 as global
NWP guidance remains bifurcated on the track of the tropical
disturbance rotating out of the Gulf of Mexico, with a spread on the
order of 200+ miles. This significant spread among the global NWP
guidance suites should continue until a closed circulation develops
with this disturbance. PoPs have increased by about 10 percent for
Thursday compared to the previous prognostications, and have been
maintained given the uncertainty involved with the track of the
aforementioned tropical system, the position and longitudinal extent
of the amplified ridge over the eastern U.S., and the position of
the entrance region to the 250 mb jet streak over the Rocky
Mountains. There is also a 20 degree spread in temperatures among
the guidance as well, and the trend towards the cooler side of the
envelope is being maintained owing to the expectation of easterly
flow lasting through at least Thursday night. Temperatures on
Thursday may hover in the upper 70s area-wide. On the other hand,
NAEFS and ENS guidance continues to indicate precipitable water
(PWAT) content of two to potentially three standard deviations above
normal advecting into portions of the CWA on Thursday, and forecast
PWAT values remain within or exceed the 99th percentile based off
sounding climatology from WFO MAF. Heavy rain remains a possibility
on Thursday into Friday given the open fetch of anomalously high
moisture content advecting northwestward from the Gulf of Mexico,
but where the heaviest rainfall occurs remains nebulous. The blended
PoPs have been accepted with cool and cloudy conditions forecast
through the end of the week. After internal coordination, the
Marginal Risk for Excessive Rainfall from WPC on Thursday/D5 has
been expanded across the central and southern portions of the CWA.

Sincavage

&&

.AVIATION...
(18Z TAFS)
Issued at 1203 PM CDT Sun Jun 16 2024

VFR with steady S-SE winds of 15-20 knots with higher gusts
through the night and especially after daybreak Monday. Could see
some LLWS at times overnight from a 45 knot LLJ should sustained
winds dip below 15 knots, but winds overall should remain very
breezy. Any TS that manage to develop late today will hold well
west of PVW-LBB before dying around sunset.

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

SHORT TERM...93
LONG TERM....09
AVIATION...93