810
FXUS64 KOUN 022337
AFDOUN

Area Forecast Discussion
National Weather Service Norman OK
637 PM CDT Thu May 2 2024

...New AVIATION...

.SHORT TERM...
(This evening through Friday)
Issued at 242 PM CDT Thu May 2 2024

Today`s forecast primarily concerns the potential for severe weather
and flooding especially across western north Texas and southern
Oklahoma. Regional surface observations and satellite data show a
cold front across northern Oklahoma early this afternoon. This front
is expected to advance southward toward a position just north of I-
44 by late afternoon. Despite rather persistent cloud cover south
of the front, rich boundary-layer moisture will still lead to
MLCAPE values around 2,000 across southwest and central Oklahoma,
while somewhat greater heating across western north Texas will
lead to MLCAPE values around 3,500. CAMs are rather bearish on
deep convective development in the face of neutral or slightly
rising heights, but storm initiation is likely across two zones.

The first zone will be just south of the front, particularly in
central Oklahoma. Rather weak deep-layer shear and steering flow
primarily moving the storms eastward will encourage the front to
undercut this convection fairly rapidly. Prior to that, a low-end
risk for damaging winds will occur, as well as the risk for one or
two non-supercellular tornadoes very early in the convective cycle
as storms have the potential to use moderately strong low-level
instability to stretch surface vorticity along the surface front.
This convection will tend to propagate southward along the cold
front over the evening.

The second, and potentially greater severe threat will occur this
afternoon and evening across western north Texas along the triple
point low. There is some uncertainty primarily related to whether or
not the triple point ends up south of our area or not, but one or a
few storms will likely develop by late afternoon. Forecast soundings
show rather straight hodographs with effective deep-layer shear of
about 40-50 knots, sufficient for splitting supercells. Given the
strong instability, large to giant hail is probable. Given the
strong low-level instability in place and the presence of the
surface low, the tornado risk will remain low, but not zero.

The threat for storms to persist overnight tonight will be somewhat
lower than over the previous several days given the lack of a
presence of a low-level jet. However, amalgamation and propagation
of cold pools will probably lead to a cluster of storms or an MCS in
the Red River Valley as the front continues to push south. A low
threat for damaging wind gusts will continue, but the greater
concern will be the potential for flooding as storms move over areas
that have been deluged over the past week. 1-hour gridded flash
flood guidance is below 1 inch across much of the Arbuckles and
surrounding terrain features. Thus, while QPFs will likely remain in
the 0.25-0.75 inch range across much of the region, there will most
likely be a couple of areas that see either training or a stalled
storm, and flash flooding could occur rather rapidly in that area.

Meister

&&

.LONG TERM...
(Friday night through next Wednesday)
Issued at 242 PM CDT Thu May 2 2024

The storm risk will reach a relative minimum for the first time in
days tomorrow, with storms exiting the southeast portion of the area
by early morning and the next round not expected until near of after
sunset out west. In the meantime, enjoy the quiet weather, with
highs reaching into the upper 70s as the moist airmass sloshes back
to the northwest across our area.

The next round of storms comes in tomorrow evening and overnight as
one or more clusters move eastward off of the Caprock and into our
area. A modest low-level jet will be present, so the threat for
damaging winds will be rather modest. The likeliest impact will be
the potential for another round of heavy rainfall across the Red
River region if an MCS is able to sustain itself.

The most widespread round of rain over the next several days will be
Saturday night, as yet another round of storms moves in from the
west. Forecast soundings show deep saturation throughout the
troposphere with rather weak steering flow. Right now, our forecast
QPFs are in the 2-3 inch range along and south of the Red River, and
this will need to be watched very closely in case a serious flash
flood concern develops.

On Monday, the potential exists for a more widespread severe weather
event to occur. Uncertainty is obviously modulated by the multiple
rounds of storms that will occur between now and then, and their
attendant impacts on the boundary layer, as well as the potential
for the primary forcing to remain well to our north across Kansas
and Nebraska. With that said, the environment now appears to support
supercells with a continued severe/flooding threat.

Who knows whether this will last, but there does not appear to be
another evident round of storms after Monday/Monday night. Buckle
up, folks. The risk for high-impact weather is definitely not over
yet.

Meister

&&

.AVIATION...
(00Z TAFS)
Issued at 634 PM CDT Thu May 2 2024

Scattered TSRA will affect all but far northwest and west central
Oklahoma terminals for the first few hours of the forecast. TSRA
chances at KDUA will hold off until late tonight if storms can
continue/redevelop along weak cold front that will stall near
southeast Oklahoma late tonight. Overall, MVFR cigs expected most
of the forecast period with veering low level winds and moist
flow. Return to southerly winds and improving cigs expected
tomorrow afternoon. Another round of TSRA possible just beyond
this forecast cycle, spread west to east.

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  60  77  63  76 /  60  20  40  80
Hobart OK         57  77  60  76 /  20  20  50  80
Wichita Falls TX  60  79  64  79 /  40  20  40  70
Gage OK           48  77  54  71 /  10  20  60  50
Ponca City OK     56  77  60  75 /  30  10  50  80
Durant OK         63  82  66  79 /  40  20  30  60

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Flood Watch until 4 AM CDT Friday for OKZ038-039-041>048-050>052.

TX...Flood Watch until 4 AM CDT Friday for TXZ090.

&&

$$

SHORT TERM...04
LONG TERM....04
AVIATION...11