Mesoscale Precipitation Discussion 0571
NWS Weather Prediction Center College Park MD
755 PM EDT Tue Jul 31 2018
Areas affected...Western North Carolina/South Carolina to
Northeast Alabama
Concerning...Heavy rainfall...Flash flooding possible
Valid 312354Z - 010300Z
Summary...Slow-moving lines of storms will likely continue to
slowly lift northeast from parts of Alabama into the western
Carolinas over the next few hours. The heaviest rainfall and the
greatest possibility of flash flooding is best from western North
Carolina southward to southwest South Carolina and northeast
Georgia where instability is best. The activity should be
diminishing with time but localized rainfall rates at or above 2
inches per hour remain possible.
Discussion...Radars from eastern/northeastern Georgia into South
Carolina showed the most active convection as of 31/2345Z
clustering around the South Carolina/Georgia state line. Rainfall
amounts in excess of 3 inches per hour were observed back around
31/23Z. While the rainfall rates will be decreasing per the HRRR,
RAP and NAM CONEST, the possibility of flash flooding will linger
for another several hours before convection weakens and rates
decrease. Area radars were not showing the same degree of
converging storm cells as were depicted earlier in the day. Flash
Flood Guidance values are likely to be dropping. Still, lingering
slow-moving storms and residual instability around the periphery
of the convective cluster could support localized heavy rainfall
and flash flooding. Certainly any ongoing flash flooding is likely
to continue until between 01/02Z and 01/03Z.
Bann
ATTN...WFO...CAE...CHS...FFC...GSP...RAH...
ATTN...RFC...SERFC...
LAT...LON 35938058 34967997 33398142 32418264 32208351
32938427 33878388 34998287 35308174
Last Updated: 755 PM EDT Tue Jul 31 2018