909
AWUS01 KWNH 011205
FFGMPD
OKZ000-011630-

Mesoscale Precipitation Discussion 0203
NWS Weather Prediction Center College Park MD
804 AM EDT Wed May 01 2024

Areas affected...Central to Eastern Oklahoma...

Concerning...Heavy rainfall...Flash flooding possible

Valid 011205Z - 011630Z

SUMMARY...Increasing warm-advection T`storms capable of 1.5-3"
over sensitive soils may pose increased runoff and spotty flash
flooding incident(s) this morning.

DISCUSSION...GOES-E 10.3um IR shows a well defined MCV from the
decaying MCS over far southeastern OK into western AR.  The MCS
has laid out a well defined outflow boundary from the MCV
along/just north of the Red River before angling back northwest
from Love county toward Custer county, OK.  VWP suite depicts a
stronger than forecast lingering LLJ with FDR suggesting 50+ kts
of south-southwesterly flow with slowly veering flow in the wake
of the MCS across southern and eastern OK.  CIRA LPW also notes an
enhanced pocket of moisture in the 850-700mb layer nearing the Red
River into SW OK which also matches up with MUCAPE axis of 2000
J/kg along the western edge of that outflow.  As such, a gradient
of unstable mid-level air with solid isentropic ascent has sparked
an NW to SE axis of thunderstorms.  Moisture is modest in the
1.25-1.4" range and flux is also supporting of up to 1.5"/hr rates
with occasional localized convergence values that may supports
spots up to 2".

With a veered steering profile, initial cells are lifting
northeastward, but propagation vectors and 500-300mb flow from the
west suggests some eastward/southeastward motions may start to
unfold over the next few hours along/near the outflow boundary.
Given continued upwind ascent (per RADAR suite), redevelopment
along the outflow as the boundary slowly drifts west, may allow
for repeating/back-building even prior to the convergence in
deeper-steering flow.  This may allow for 1 to 2 hours of duration
and allow for spots of 1.5-3" totals.  The bad news, the
placement/track of the southern axis across south-central OK will
cross sensitive, recently flooded areas...where AHPS depicts a
broad area of 250%+ of 7day rainfall anomalies from Cotton to S
Osage county and southeastward, with spots of 500%+ from Love to
Seminole/Hughes county.  So currently, not ideally aligned, but
still concerning enough to suggest spots/localized incidents of
flash flooding are possible through this morning.

Further north near the KS/OK border...Another similar axis has
developed along an exposed area of return southeasterly flow not
generally obstructed by ongoing convection to the south and
southwest.  The surface front is also sagged across this area
while the main LLJ core lifts the warm front further west.  So a
bit of enhanced convergence across areas hit hard last night,
bleeding into Osage county...may see a similar if slightly muted
situation as described above with a spot of flash flooding still
possible as well before diurnal convective minima/stabilization
occurs later this morning.

Gallina

...Please see www.wpc.ncep.noaa.gov for graphic product...

ATTN...WFO...OUN...TSA...

ATTN...RFC...ABRFC...NWC...

LAT...LON   36979725 36879643 36219563 35449513 34869507
            34119534 33889613 33879644 34029699 34509783
            35219842 35579833 36119761 36349758 36719748