AWUS01 KWNH 231311
FFGMPD
LAZ000-ARZ000-TXZ000-OKZ000-231809-

Mesoscale Precipitation Discussion 0506
NWS Weather Prediction Center College Park MD
909 AM EDT Tue Jun 23 2026

Areas affected...Southeast OK, Northeast TX, Southwest AR

Concerning...Heavy rainfall...Flash flooding likely

Valid 231309Z - 231809Z

Summary...Flash flooding is currently ongoing along the Red River.
Backbuilding convection producing localized 2?3"/hr rainfall rates
will likely persist for at least a few more hours, leading to
additional and potentially significant flash flooding.

Discussion...As of 13z, Regional radar and IR imagery show a
persistent, organized area of robust convection anchored along the
Red River near the intersection of the Texas, Oklahoma, and
Arkansas borders. This backbuilding convection is focused along a
well-defined axis of low-level convergence. The mesoscale
environment remains exceptionally moist and supportive of heavy
rainfall rates, with precipitable water values in excess of 2".
This is driving efficient precipitation production, with localized
rainfall rates of 2-3"/hr within the strongest convective cores.

Recent high-resolution model guidance has suggested that the
low-level jet and its associated low-level convergence should be
on a downward trend this morning. This should result in a gradual
decrease in convective intensity and coverage as the morning
progresses. However, current observations contradict this modeled
weakening from the HRRR, with both radar and IR imagery showing
continued persistence and updraft maintenance. It seems probable
that the ongoing convection is organized enough to have locally
enhanced the low-level convergence via mesoscale boundaries.

The evolution later this morning remains a bit uncertain. MUCAPE
over 2000 J/kg supports deep convective growth; however, how the
low-level convergence evolves will be the key factor. Any subtle
uptick in the low-level jet (as hinted at by recent runs of the
HRRR) could be enough to sustain this activity, with just some
slow southward propagation. Conversely, it is also possible that
the convergence eventually weakens just enough to decrease
convective coverage and organization with time. Given these
conflicting signals, near-term trends will need to be monitored closely.

Either way, at least a few more hours of persistence appears
likely, with training and backbuilding convection continuing. With
highly efficient 2?3"/hr rainfall rates falling over rapidly
saturating ground conditions, and with flash flooding already
ongoing across the region, additional instances of flash flooding
are likely. Given the intense rates and expected accumulations,
some of this flash flooding may become locally significant in
nature over the next few hours.

Chenard

ATTN...WFO...FWD...OUN...SHV...TSA...

ATTN...RFC...ORN...TUA...NWC...

LAT...LON 34599603 33749403 33039351 32719374 33269523
33779622

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