Mesoscale Precipitation Discussion 0552
NWS Weather Prediction Center College Park MD
815 PM EDT Sat Jul 28 2018

Areas affected...Southeast NC into northeast SC

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

Valid 290015Z - 290315Z

SUMMARY...Slow moving cells in a high moisture environment could
train during the early evening, posing a continued flash flood
threat.

DISCUSSION...Convection continues to form and move in the best
instability axis (with MLCAPE values between 1000-1500 J/KG
extending from central NC into northeast SC). Ahead of the frontal
boundary extending across roughly the same area, scattered storms
are producing hourly rainfall rates over 2.00 inches over Bladen
and Pender counties in NC. The deep moisture source remains in
place, with precipitable water values between 1.75/2.00 inches.

The slow storm motions are the main flash flood threat through the
early evening hours, as storm motions are expected to remain under
10 knots. The most recent HRRR showed local 2.00/3.00 inches of
rainfall (at least locally) east of the front in the moisture
plume through about 29/03z. Heavy rainfall early today has
resulted in wet soils, especially across southeast NC.

Model soundings showed instability waning slowly, finally dropping
below 500 J/KG of MUCAPE by about 29/04z. Despite the overall
weakening trend, based on radar hourly rainfall rates, a flash
flood threat remains in place. Because of the scattered nature of
the activity, flash flooding is considered possible.

Hayes

ATTN...WFO...CAE...ILM...MHX...RAH...

ATTN...RFC...SERFC...

LAT...LON   35587792 35507691 34897700 33757946 34818019
            34878010 35187935