MESOSCALE PRECIPITATION DISCUSSION 0214
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
955 AM EDT MON MAY 28 2018

AREAS AFFECTED...EASTERN SC...SOUTHEAST NC

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 281355Z - 281950Z

SUMMARY...BANDS OF VERY HEAVY RAINFALL ADVANCING SLOWLY NORTH THIS
MORNING WILL ENCOURAGE RUNOFF PROBLEMS AND SOME FLASH FLOODING.

DISCUSSION...A DEEP LAYER SOUTHERLY TRANSPORT OF TROPICAL MOISTURE
CONTINUES NORTHWARD THIS MORNING INTO THE SC/NC COASTAL
PLAIN...WITH THE LATEST GOES-16 CLEAN IR SATELLITE IMAGERY
DEPICTING MULTIPLE EMBEDDED CONVECTIVE BANDS WITH SOME CLOUD-TOP
COOLING ACROSS AREAS OF FAR EASTERN SC INVOLVING GEORGETOWN AND
HORRY COUNTIES...AND ALSO OVER SOUTHEAST NC INVOLVING COLUMBUS AND
BRUNSWICK COUNTIES.

THE CONVECTION IS FOCUSING WITHIN AN AREA OF FOCUSED LOW LEVEL/850
MB CONVERGENCE AND RELATIVELY DIVERGENT FLOW ALOFT AROUND THE FAR
NORTHEASTERN PERIPHERY OF SUBTROPICAL STORM ALBERTO THAT IS
CURRENTLY APPROACH THE FL PANHANDLE. THE DEEP SOUTHERLY TROPICAL
FETCH OF MOISTURE IS CHARACTERIZED BY PWATS OF 2.2 TO 2.4 INCHES
AS PER 12Z RAOB AND GPS-DERIVED PWATS...AND GIVEN A HIGHLY
CONCENTRATED MOISTURE IN THE 500/300 MB LAYER...THE ENVIRONMENT IS
HIGHLY CONDUCIVE FOR EXTREME RAINFALL RATES THAT MAY EXCEED 3
INCHES/HR.

THE LATEST HRRR/HRRRX GUIDANCE IS SHOWING A LIKELIHOOD OF TRAINING
CONVECTIVE BANDS LIFTING UP NORTH IN OFF THE ATLANTIC OCEAN AND
INLAND ACROSS THE IMMEDIATE SC/NC COASTAL PLAIN OVER THE NEXT
SEVERAL HOURS WITH SOME EXTREMELY HEAVY RAINFALL POTENTIAL. IN
FACT...THE 12Z RUNS OF THESE MODELS ARE SHOWING AS MUCH AS 5 TO 8
INCHES OF RAINFALL POTENTIAL GOING THROUGH MID-AFTERNOON...WITH
SOME OF THE GREATEST POTENTIAL EXPECTED TO BE AROUND THE MYRTLE
BEACH SC AREA ALONG WITH ADJACENT TOWNS TO THE NORTH INTO
SOUTHEAST NC WEST OF THE WILMINGTON AREA. ENHANCED RUNOFF PROBLEMS
AND FLASH FLOODING WILL BE POSSIBLE.

ORRISON

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

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

LAT...LON   35077685 34617644 34467716 34327744 33907770
            33847812 33727851 33387885 32877918 32497952
            32588004 33148021 33888021 34208006 34577975
            34787931 34917877 35007779