Mesoscale Precipitation Discussion 1075
NWS Weather Prediction Center College Park MD
854 AM EST Fri Dec 28 2018

Areas affected...Northern GA...Western NC...Southwest VA...Eastern
KY

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

Valid 281354Z - 281854Z

Summary...Widespread moderate to locally heavy rainfall over
saturated soils could lead to flooding across the area through
this afternoon, especially over sensitive locations in low lying
areas.

Discussion...Broad southwest flow aloft has continued to surge a
plume of highly anomalous moisture into the southern and central
Appalachians, evident by the blended GPS product showing PWATs
1.2-1.3" as far north as southwest VA. This should continue to
advect northward into the afternoon hours. A mesoanalysis showed
MUCAPE of 500 J/kg extending as far north toward the NC/VA border.
850 mb flow remains strong (40-50 kts) with some upslope component
that should favor rainfall across the terrains areas. With these
ingredients in place, widespread moderate to locally heavy
rainfall is likely to continue into the afternoon.

Soils are extremely saturated given 24-hr rainfall totals as high
as 2-4" across portions of the southern/central Appalachians.
14-day departures from normal are running 200-400 percent of
normal.

Radar imagery shows pockets of hourly rates exceeding 0.5", which
is likely to initiate problems for sensitive and low-lying areas.
Hi-res models show the potential for additional amounts of 1-2"
with some local amounts as high as 3" possible in some of the
favored upslope areas.

As a result, flooding is possible across much of the southern and
central Appalachians into the afternoon hours.

Taylor

ATTN...WFO...FFC...GSP...JKL...MRX...RAH...RLX...RNK...

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

LAT...LON   37738122 37537975 37227900 36587925 35318075
            34308208 32888510 34868535 35848454 36968368
            37478273