MESOSCALE PRECIPITATION DISCUSSION 0140
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
225 PM EDT SUN JUN 30 2013
 
AREAS AFFECTED......CENTRAL NC TO EASTERN PA/WESTERN NJ AND
SOUTHERN NY STATE... 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 301824Z - 302124Z
 
SUMMARY...FLASH FLOODING IS POSSIBLE FROM CENTRAL NC TO PARTS OF
THE NRN MID-ATL STATES... WITH SEVERAL CONVECTVE LINE SEGMENTS
CAPABLE OF PRODUCING 1-3 INCH/HR RAIN RATES... WHILE DRIFTING
SLOWLY OFF TO THE NNE. 

DISCUSSION...A DEEP ANOMALOUS PLUME OF TROPICAL MOISTURE IS
ADVANCING AND EXPANDING NORTH AND WEST INTO THE SOUTHEAST AND
MID-ATL STATES OR AROUND THE WRN PERIPHERY OF AN IMPRESSIVE
BERMUDA RIDGE OUT OVER THE ATLANTIC OCEAN THIS AFTN. GFS AND ECMWF
STANDARDIZED PW ANOMALIES SUGGEST VALUES 4 TO 5 TIMES ABOVE AVG.
WATER VAPOR IMAGERY DETECTS TWO SHORT WAVE IMPULSES RIDING UP A
STATIONARY SURFACE/850MB FRONT IN AN AREA PRIME FOR FAVORABLE
UPPER DIFLUENCE... THUS PRODUCING TWO ORGANIZED AREAS OF
CONVECTION BUT SEVERAL LINE SEGMENTS FROM NC TO PA/NJ. THIS
ACTIVITY IS FLOURISHING THIS AFTN DUE TO THE STRONG
HEATING/DESTABILIZATION AND SHOULD PERSIST FOR THE NEXT FEW HRS...
AS MORNING RAOBS INDICATED ONLY 15KT 850MB SWRLY FLOW AND
SOUNDINGS FAVORABLE FOR SLIGHT BACKBUILDING DEVELOPMENT. THE
LOWEST 1 HRLY FFG IS ACROSS CENTRAL NC... BETWEEN CLT AND RDU...
AND ACROSS PORTIONS OF NJ/ERN PA AND SRN NY STATE... INCLUDING THE
PHL AND EWR METRO AREA AND NEARBY TERRAIN. THE AVAILABLE MOISTURE
CONTENT WILL EASILY ALLOW MORE ORGANIZED ACTIVITY TO PRODUCE 1-3
INCH/HR RAIN RATES FOR POSSIBLE FLASH FLOODING BUT DUE TO
CONVECTIVE ELEMENTS AND SMALL SCALE NATURE OF THE ACTIVITY... NOT
ALL OF THE EXPANDED AREA WILL SEE SUCH CONDITIONS.  

MUSHER

ATTN...WFO...BOX...OKX...ALY...PHI...BGM...AKQ...CTP...LWX...
RAH...RNK...CAE...GSP...

ATTN...RFC...MARFC...NERFC...SERFC...

LAT...LON   39087761 38277841 37627910 36467942 35898051 34908095
            34778088 34728013 35597877 36377807 37147799 38207733
            38717696 39007600 39507487 40557441 41217399 42077298
            42757305 42717375 42137438 41887519 41397607 40477645
            39667700 39087761