MESOSCALE PRECIPITATION DISCUSSION 0437
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
511 PM EDT MON JUL 03 2017

AREAS AFFECTED...NORTHERN MS...NORTHERN AL...NORTHWEST
GA...CENTRAL/EASTERN TN...CENTRAL/SOUTHEAST KY...EXTREME SOUTHWEST
VA...EXTREME SOUTHWEST NC

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

VALID 032110Z - 040015Z

SUMMARY...SCATTERED CLUSTERS OF HEAVY SHOWERS AND THUNDERSTORMS
WILL BE EXPECTED THROUGH THE EARLY EVENING HOURS. SOME LOCALIZED
RUNOFF/FLASH FLOODING CONCERNS WILL EXIST.

DISCUSSION...A VERY WELL-DEFINED A LONG LIVED MCV MOVING ACROSS
FAR NORTHEAST AR CURRENTLY IS HELPING TO FACILITATE SOME
ADDITIONAL DISORGANIZED BANDS/CLUSTERS OF SHOWERS AND
THUNDERSTORMS ACROSS THE TN VALLEY THIS AFTERNOON. THE LOW LEVEL
FLOW IS RATHER CONFLUENT ACROSS THE EASTERN AND ESPECIALLY THE
SOUTHERN FLANK OF THE MCV WHICH IN CONJUNCTION WITH A MODERATELY
UNSTABLE AIRMASS AND MOISTURE-RICH BOUNDARY LAYER IS HELPING TO
PRODUCE SHOWERS AND THUNDERSTORMS WITH INTENSE RAINFALL RATES
REACHING OVER 2 INCHES/HR.

THE CONCERN OVER PARTS OF CENTRAL/SOUTHERN KY IS THE SLOW CELL
MOTION...WHILE FARTHER SOUTH OVER NORTHERN MS/AL IT IS AN
ENVIRONMENT A LITTLE MORE CONDUCIVE FOR REPEATING CELL ACTIVITY
GIVEN THE CONFLUENT LOW LEVEL FLOW RELATIVE TO THE DEEPER MEAN
LAYER FLOW WHICH IS OUT OF THE WEST-SOUTHWEST.

MUCH OF THE CONVECTION WILL BE HEAVILY TIED INTO THE DIURNAL
HEATING CYCLE FOR THE REMAINDER OF THE DAY AS OVERALL FORCING IS
NOT THAT STRONG. THEREFORE...EXPECT SOME WEAKENING OF THE CELLS
TOWARD 00Z. UNTIL THAT TIME...EXPECT SOME POCKETS OF 2 TO 4 INCH
RAINFALL TOTALS WHICH MAY RESULT IN SOME POCKETS OF RUNOFF
PROBLEMS AND/OR FLASH FLOODING. SOME OF THE RECENT HEAVY RAINFALL
AT LEAST LOCALLY MAY TEND TO ALSO ENHANCE THE THREAT A BIT.

ORRISON

ATTN...WFO...BMX...FFC...GSP...HUN...JAN...JKL...LMK...MEG...
MRX...OHX...

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

LAT...LON   37748468 37688389 37238274 36208271 35268363
            34348501 34068581 33838711 33778836 33678968
            34089019 34638997 35038903 34968762 35038680
            35418616 35798578 36508561 37228586 37618548