MESOSCALE PRECIPITATION DISCUSSION 0519
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
530 PM EDT FRI SEP 25 2015
 
AREAS AFFECTED...EASTERN NC 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 252130Z - 260230Z
 
SUMMARY...ADDITIONAL CONVECTION TRACKING NORTH ACROSS EASTERN NC
COULD PRODUCE HEAVY RAINFALL AND FLASH FLOODING INTO THE EVENING
HOURS. 

DISCUSSION...THE IR SATELLITE LOOP AND MHX RADAR CONTINUE TO SHOW
CONVECTION BLOOMING IN THE HIGH MOISTURE CONTENT AIR (THE LATEST
BLENDED TOTAL PRECIPITABLE WATER IMAGES SHOWING VALUES AS HIGH AS
2.50 INCHES... WHICH IS BETWEEN TWO AND THREE STANDARD DEVIATIONS
ABOVE THE MEAN) OFF THE EASTERN NC COAST. THUS FAR...THE BEST
INSTABILITY HAS REMAINED JUST OFFSHORE OF THE NC/SC... WITH MUCAPE
VALUES OF 500-1000 J/KG REMAINING FURTHER SOUTH INTO CENTRAL SC.
RAINFALL RATES IN THE MAINLY STRATIFORM AREA OVER EASTERN NC HAVE
BEEN AROUND 0.50 INCHES.

THROUGH THE EVENING HOURS...CONVECTION IS EXPECTED TO TRACK
NORTHWARD ACROSS EASTERN NC...AND BASED ON THE FORECAST MUCAPE
PLACEMENT...THE STRONGEST CONVECTION SHOULD REMAIN OVER/CLOSE TO
THE NC OUTER BANKS. THE 19Z HRRR/RAP SHOWED 3-5 INCHES OF RAINFALL
OVER THE OUTER BANKS...STRETCHING BACK ACROSS THE NORTHERN PAMLICO
SOUND INTO DARE AND TYRELL COUNTIES IN NC. 

BASED ON THE FORECAST INSTABILITY PROFILES AND THE TRACK OF
CONVECTION SO FAR LATE THIS AFTERNOON...THAT PLACEMENT MAY BE TOO
FAR WEST. AT THIS POINT...BASED ON RADAR/SATELLITE INTERPOLATION
AND HIGH RESOLUTION QPF MAXIMA PLACEMENT...THE HIGHEST RAINFALL
RATES ARE EXPECTED OVER THE OUTER BANKS AND NEAR THE PAMLICO
SOUND. 

IN THESE AREAS...AN ADDITIONAL 2-4 INCHES OF RAINFALL CAN BE
EXPECTED. THERE IS A POSSIBILITY THAT THE HEAVIEST RAINFALL COULD
REMAIN JUST OFFSHORE...BASED ON RADAR AND SATELLITE TRENDS.
HOWEVER...PORTIONS OF EASTERN NC BETWEEN ILM AND NKX HAS RECEIVED
5-7 INCHES OF RAINFALL IN THE PAST 24 HOURS...SO ANY ADDITIONAL
HEAVY RAIN COULD RESULT IN FLASH FLOODING. 

HAYES

ATTN...WFO...MHX...

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

LAT...LON   36057566 35667523 35237523 34877553 34747596 
            34807639 35337615 35827601