MESOSCALE PRECIPITATION DISCUSSION 0216
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
240 PM EDT MON JUL 21 2014
 
AREAS AFFECTED...CNTR/ERN GA INTO CNTRL/ERN SC AND SERN NC 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 211839Z - 220039Z
 
SUMMARY...SLOW MOVING THUNDERSTORMS ARE EXPECTED TO INCREASE IN
COVERAGE ACROSS GA AND ERN SC WITHIN A REGION OF VERY HIGH
MOISTURE...LOCATED EAST OF A SLOW MOVING MID-LEVEL LOW THROUGH
00Z. DESPITE HIGH FLASH FLOOD GUIDANCE...SLOW MOVING STORMS COULD
ALLOW 4-6 INCHES OF RAIN IN A FEW LOCATIONS CAUSING A THREAT FOR
FLASH FLOODING THROUGH 00Z.

DISCUSSION...VISIBLE SATELLITE IMAGERY FROM 18Z SHOWED A RELATIVE
REGION OF CLEAR SKIES LOCATED SOUTH OF A QUASI-STATIONARY FRONT
EXTENDING WWD ACROSS THE CAROLINAS AND NORTH OF A WEAK 850-700 MB
CONVERGENCE AXIS SLOWLY DRIFTING NORTH ACROSS SWRN GA. THE REGION
HAS LITTLE TO NO CAP AND NUMEROUS TCU ARE EVIDENT ON SATELLITE
WITH SEVERAL THUNDERSTORMS VISIBLE ON RADAR IMAGERY. 

GIVEN BLENDED TOTAL PRECIPITABLE WATER VALUES OF OVER 2 INCHES
EXTENDING INLAND ROUGHLY 100 MILES FROM THE SOUTHEAST
COASTLINE...WHICH IS ABOUT 2 STANDARD DEVIATIONS ABOVE THE
MEAN...RAINFALL RATES OF 1 TO 2 IN/HR WILL BE POSSIBLE. 850-200 MB
MEAN WIND VECTORS ARE VERY WEAK...LESS THAN 15 KTS WHICH WILL
PROMOTE SLOW MOVEMENT OF STORMS AND BACKBUILDING WITH THE
POTENTIAL FOR A QUICK 4 TO 6 INCHES OF RAINFALL OVER A 3 TO 4 HOUR
PERIOD. SEVERAL OF THE 12Z HI-RES MODELS AND RECENT RUNS OF THE
HRRR ARE HINTING AT THIS REGION THROUGH 00Z WHICH MAY CAUSE A FEW
FLASH FLOOD PROBLEMS...ESPECIALLY NEAR AND EAST OF THE I-95
CORRIDOR.

OTTO

ATTN...WFO...RAH...ILM...CHS...CAE...JAX...FFC...TAE...

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

LAT...LON   30818143 31258276 32058410 33308402 33228222 33888115
            34368022 34917905 34257767 33167870 31948049 30818143