MESOSCALE PRECIPITATION DISCUSSION 0101
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
321 AM EDT THU JUN 13 2013
 
AREAS AFFECTED...EASTERN IN/CENTRAL OH/NORTHERN WV/WESTERN PA... 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 130721Z - 131121Z
 
SUMMARY...FAVORABLE UNIDIRECTIONAL FLOW OUT OF THE WEST-SOUTHWEST
SHOULD MAINTAIN A THREAT FOR FLASH FLOODING ACROSS A BROAD AXIS OF
CONVECTION OVER THE AFFECTED AREAS.
 

DISCUSSION...RADAR IMAGERY DURING THE PAST COUPLE OF HOURS
SUGGESTS BETTER CONVECTIVE ORGANIZATION AS THE LEADING EDGE HAS
BECOME DEFINED BY A BOWING LINE. MEANWHILE...AN ELONGATED
STRATIFORM REGION CONTINUES TO DUMP ADDITIONAL HEAVY RAINFALL
ACROSS CENTRAL IN/OH. FORECAST SOUNDINGS CONTINUE TO INDICATE VERY
FAVORABLE THERMODYNAMICS PROFILES FOR EXCESSIVE RAINFALL GIVEN THE
UNIDIRECTIONAL TROPOSPHERIC FLOW AND TALL/SKINNY CAPE.
ADDITIONALLY...THE DEEP-LAYERED WEST-SOUTHWESTERLY FLOW CONTINUES
TO ADVECT THE HIGHEST PWAT AIR MASS INTO THE OH VALLEY. THE 06Z
RAP SUGGESTS THE ATMOSPHERE IS RELATIVELY UNCAPPED WITH AMPLE
INSTABILITY AS MLCAPE VALUES REACH THE 1000-1500 J/KG RANGE.
THUS...LITTLE CHANGE IN THE INTENSITY OF THE CONVECTION IS TO BE
EXPECTED DURING THE NEXT SEVERAL HOURS.

RADAR-DERIVED QPE SHOWS HOURLY RAINFALL RATES APPROACHING 2 TO 3
INCHES WHICH IS IN AGREEMENT WITH MANY OF THE COOPERATIVE REPORTS
ACROSS WESTERN OH. AS THE SYSTEM PROGRESSES EASTWARD...SUCH
LOCALIZED RATES SHOULD CONTINUE. FURTHER...TRAINING/BACKBUILDING
CONVECTION CAN BE EXPECTED AS CORFIDI VECTORS SHOW STORM MOTIONS
OF LESS THAN 5 KNOTS OUT OF THE WEST TO NORTHWESTERLY DIRECTION.


RUBIN-OSTER

ATTN...WFO...CTP...LWX...PBZ...RLX...CLE...ILN...IWX...IND...

ATTN...RFC...MARFC...OHRFC...

LAT...LON   39818505 40548455 40968288 41218123 41577999 41517952
            41247911 40677878 39937884 39417912 39287965 39078099
            39018252 39138459 39818505