MESOSCALE PRECIPITATION DISCUSSION 0260
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
844 AM EDT SUN MAY 29 2016
 
AREAS AFFECTED...PORTIONS OF SC AND EASTERN GA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 291243Z - 291843Z
 
SUMMARY...THUNDERSTORMS NEAR AND WEST OF THE CENTER OF TROPICAL
DEPRESSION BONNIE COULD HAVE HOURLY RAIN RATES UP TO 2.5".  FLASH
FLOODING IS A CONCERN.

DISCUSSION...SHOWERS AND THUNDERSTORMS WITH HEAVY RAIN RATES HAVE
BEEN WITNESSED BETWEEN BEAUFORT SC AND SAVANNAH GA THIS MORNING. 
AN UPPER LEVEL CIRCULATION ACROSS EASTERN GA HAS BEEN INDUCING
SOUTH-SOUTHEAST VERTICAL WIND SHEAR OVER THE CENTER OF BONNIE,
WHICH HAS HELPED DISPLACE CONVECTION TO ITS WESTERN QUADRANT.  AT
LOW-LEVELS, 850 HPA INFLOW OF 25-30 KTS OUT OF THE EAST TO
NORTHEAST HAS BEEN ADVECTING MUCAPES OF 1000-2000 J/KG FROM THE
UPPER SC AND NC COAST.  PRECIPITABLE WATER VALUES BETWEEN 1.6-2.2"
EXIST HERE PER RECENT GPS VALUES AND THE 12Z CHS SOUNDING.  WET
BULB ZERO VALUES ARE BEYOND 14,000 FEET, WHICH ALLOWS WARM RAIN
PROCESSES TO BE IN PLAY.  CIN CONTINUES TO EXIST ACROSS PORTIONS
OF THIS REGION, WHICH IN SOME AREAS COULD PERSIST INTO THE
AFTERNOON HOURS DUE TO PERSISTENT CLOUD COVER.

THE MESOSCALE/CAM GUIDANCE IS NEARLY UNANIMOUS IN  SHOWING HEAVY
RAIN ACROSS THIS REGION.  THERE IS A GENERAL SIGNAL FOR LOCAL
AMOUNTS OF 3-6", WHICH COULD FALL QUICKLY.  THE AVAILABLE
INGREDIENTS SUPPORT HOURLY RAIN RATES UP TO 2.5".  FLASH FLOODING
IS CONSIDERED POSSIBLE WITHIN AND NEAR THE DEFINED AREA.  USED
EXTRAPOLATION FROM THEIR LAST ADVISORY AND THE SYSTEM'S CURRENT
POSITION TO INDICATE WHERE ITS POSITION WOULD BE TOWARDS 19Z.

ROTH

ATTN...WFO...CAE...CHS...FFC...ILM...

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

LAT...LON   34188076 34167952 33147940 32757975 32238061 
            31988126 32068200 32838200 33618164