Mesoscale Precipitation Discussion 0041
NWS Weather Prediction Center College Park MD
246 PM EST Sat Feb 15 2025

Areas affected...Portions of the OH/TN Valleys and Central
Appalachians

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

Valid 151945Z - 160145Z

SUMMARY...Locally significant flash flooding is expected going
into the evening hours from persistent heavy rainfall over
saturated soils.

DISCUSSION...The latest GOES-E IR satellite imagery along with
dual-pol radar shows an expansive area of heavy rain continuing to
advance west to east across central and eastern KY and into
southwest VA and southern WV. The activity continues to be
associated with strong warm air advection which is being aided by
a powerful southwest low-level jet of 40 to 60+ kts overrunning a
strong frontal zone.

This is driving very strong moisture transport with magnitudes in
the SFC/850 mb layer of as much as 320 kg/m/s aiming across much
of western and central TN and toward southern KY as seen in the
experimental CIRA-LVT (Layered Vapor Transport) imagery. Some very
modest instability with MUCAPE values of as much as 100 to 250
J/kg is noted over the region and this has been supporting some
occasional elevated convective elements.

Over the next several hours heading into the evening, there will
continue to be a west to east axis of heavy rainfall given the
level of strong isentropic ascent and frontogenetical forcing, but
as a warm front lifts north with time, this band of heavy rainfall
should also gain latitude with the rain eventually getting into
more of north-central to northeast KY and central WV.

The rainfall rates should be able to at least occasionally reach
into the 0.50" to 0.75"/hour range, and especially with any
stronger convective elements that continue to materialize. These
rates and overall persistence of heavy rainfall should support
additional rainfall totals by early this evening of 1 to 2 inches
with locally higher amounts.

Many areas have ongoing areal flooding and flash flooding, and
with extremely sensitive/saturated soil conditions and very high
streamflows, much of the additional rainfall will lead to
immediate runoff and potentially support significant flash
flooding for some locations. This will include areas of the
central Appalachians for locations that currently also have a
melting snowpack and thus added water runoff concerns.

Orrison

ATTN...WFO...ILN...JKL...LMK...LWX...MRX...OHX...RLX...RNK...

ATTN...RFC...LMRFC...MARFC...OHRFC...SERFC...NWC...

LAT...LON   38868096 38507991 38007962 37197993 36698093
            36348411 36568591 37358642 37988611 38578432
            38848255