MESOSCALE PRECIPITATION DISCUSSION 0350
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
248 AM EDT TUE JUL 14 2015
 
AREAS AFFECTED...SOUTHERN INDIANA...SOUTHERN OHIO...WEST
VIRGINIA...WESTERN VIRGINIA...EASTERN KENTUCKY...NORTHEAST
TENNESSEE...WESTERN NORTH CAROLINA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 140648Z - 141248Z
 
SUMMARY...LARGE AREA OF SATURATED SOILS IN BROADLY CONVECTIVE
ENVIRONMENT ACROSS OHIO RIVER VALLEY TO CONTINUE LIKELY FLASH
FLOODING THREAT. IN PARTICULAR...TWO CORRIDORS OF TRAINING
CONVECTION CAPABLE OF INCREASED THREAT. 

DISCUSSION...SYNOPTIC SETUP PER 0451Z SPENES MESSAGE DESCRIBES
WELL THE LARGE CONVECTIVE COMPLEX ACROSS OHIO RIVER VALLEY. 
RECENT TRENDS ARE BEGINNING TO EVOLVE INTO A BROAD THREAT OF
CONTINUED CONVECTION BUT WITH TWO MORE NARROWLY FOCUSED CORRIDORS
OF CONVECTION.  THE FIRST ACROSS SOUTHERN OHIO INTO WEST VIRGINIA
IS IN ASSOCIATION WITH ENHANCED LOW TO MID-LEVEL FLOW IN ADVANCE
OF WELL DEFINED MCV JUST SOUTH OF CMH.  THIS ASCENT ALONG THE
EFFECTIVE WARM FRONT OF THE MCV HAS LEAD LARGE OVERTURNING ACROSS
WEST VIRGINIA UNDER BETTER LEFT EXIT JET DYNAMICS AND PULSES OF
INCREASED DIVERGENCE ACROSS THE STATE FORECAST BY THE RAPID IN THE
DIFFLUENT REGION...SHOULD SUPPORT CONTINUED CONVECTION.  THOUGH
INSTABILITY IS LESS THAN 500 J/KG IN WV AND MUST BE TRANSPORTED IN
FROM EASTERN KENTUCKY WHERE MUCAPES ARE 2000-3000 J/KG.  RATES OF
1-1.5"/HR ARE LIKELY IN THE NEAR TERM. WITH UPSTREAM CONVECTION
FLOW MAY BE ROBBED ENOUGH OVER THE LONGER TERM TO REDUCE
CONVECTIVE DEVELOPMENT BUT MAINTAIN VERY EFFICIENT MODERATE SHIELD
PRECIPITATION AS IT ROLLS INTO WESTERN VIRGINIA TOWARD MORNING. 
STILL GIVEN LOW GUIDANCE HERE...EVEN RATES OF .5-.75"/HR WILL POSE
CONTINUED FLASH FLOOD THREAT.

INDIANA/KENTUCKY...
STRONG 30-40KT LOW LEVEL JET CONTINUES TO FOCUS CONVECTION WITH
STRONG MOISTURE CONVERGENCE ALONG WARM FRONT DRAPES ACROSS CENTRAL
INDIANA.  HIGH MUCAPES IN EXCESS OF 4000 J/KG AND WITH TOTAL PWATS
JUST ABOVE 2" CELL EFFICIENCY SHOULD SUPPORT RATES OF 2-2.5"/HR TO
CONTINUE.  UPPER LEVEL JET SPEED MAX UPSTREAM IN DIFFLUENT FLOW
ACROSS THE DISCUSSION AREA WILL CONTINUE TO SUPPORT BACKBUILDING
CELLS THAT HAVE THE POTENTIAL FOR SOME TRAINING ESPECIALLY AS NEW
CELLS OUT OF EASTERN ILLINOIS INTERSECT THE FRONTAL BOUNDARY FROM
NEAR TERRA HAUTE TOWARD LOUISVILLE AND INTO CENTRAL KENTUCKY. 
TOTALS OF 3-5" ARE POSSIBLE ALONG THE TRAINING TRACK. 


THERE IS LIMITED HI-RESOLUTION MODEL SUPPORT FOR A BEST
SOLUTION...BUT THERE ARE MODELS WITH GOOD IDEA OF THE TRACK OF THE
CORRIDOR SUCH AS THE FSL HRRR BUT HAS NOT HANDLED THE MAGNITUDE OF
THE RAINFALL. THE 00Z NMMB MAY BE THE BEST COMBINATION OF
MAGNITUDE AND TRACK THOUGH APPEARS TO BE UNDERPLAYING THE
CONVECTIVE STRENGTH WITH THE WESTERN CONVECTION. OVERALL...THIS
DOES NOT PROVIDE MUCH CONFIDENCE FOR THE LONGER TERM CONFIDENCE AS
THE CONVECTION REACHES THE HIGHER TERRAIN ACROSS SOUTHEAST
KENTUCKY/WESTERN VIRGINIA AND NORTHEAST TENNESSEE BY EARLY MORNING
HOURS...THOUGH WOULD SUSPECT CONVECTION WILL MAINTAIN STRENGTH
LONGER THAN HI-RES MODELS SUGGEST. 


GALLINA

ATTN...WFO...GSP...ILN...IND...JKL...LMK...MRX...OHX...PAH...
PBZ...RAH...RLX...RNK...

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

LAT...LON   39958564 39548440 39288336 39408212 39898096 
            39338045 38618004 37567936 36667985 35768068 
            35278311 36538530 38068690 38828744 39228737