Graphic for MPD #0319

MESOSCALE PRECIPITATION DISCUSSION 0319
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
942 AM EDT TUE JUN 13 2017

AREAS AFFECTED...PORTIONS OF SOUTHERN OH, EASTERN KY, AND WV

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 131341Z - 131941Z

SUMMARY...THUNDERSTORMS HAVE BEEN INCREASING IN COVERAGE IN AND
NEAR THE UPPER OH VALLEY SINCE 10Z.  HOURLY RAIN RATES UP TO 2"
WITH LOCAL AMOUNTS OF 3-5" ARE EXPECTED INTO THIS AFTERNOON.

DISCUSSION...AN UPPER LOW MOVING INTO SOUTHERN WV APPEARS TO BE
RESPONSIBLE FOR THE EARLY CONVECTIVE UPTICK ACROSS SOUTHERN OH AND
WV SINCE 10Z, HOURS AHEAD OF WHAT HAS BEEN INDICATED ON THE
MESOSCALE GUIDANCE.  RECENT SPC MESOSCALE ANALYSES SHOW CIN
ALREADY ERODING ACROSS KY AND WV.  PRECIPITABLE WATER VALUES OF
1.5-1.75" LURK ACROSS THE REGION PER RECENT GPS DATA.  INFLOW AT
850 HPA IS CONVERGENT FROM THE WEST-NORTHWEST AT 15-20 KTS,
SLIGHTLY EXCEEDING THE MEAN 850-400 HPA WIND, DRAWING IN MLCAPES
OF 1000-2000 J/KG FROM SOUTHERN OH AND KY.  BULK SHEAR ACROSS THE
REGION IS BELOW 25 KTS PER SPC MESOANALYSIS.  DESPITE THAT, SOME
ORGANIZED STRUCTURES HAVE BEEN APPEARING SPORADICALLY IN RADAR
IMAGERY.

LOW-LEVEL INFLOW SHOULD STAY AT THIS MAGNITUDE OVER THE NEXT
SEVERAL HOURS, IMPLYING THAT MOST CONVECTION SHOULD BE PULSE --
CELL MERGERS SHOULD BE THE MAIN SOURCE FOR LOCALLY HEAVY RAINFALL.
 INCREASING INSTABILITY WITH TIME DUE TO DAYTIME HEATING SHOULD
ALLOW FOR ANOTHER 1000+ J/KG OF MLCAPE AND FOR THUNDERSTORMS TO
CONTINUE TO BUILD EAST OF THE INSTABILITY POOL ACROSS
NORTH-CENTRAL KY ACROSS SOUTHERN OH, EASTERN KY, AND SOUTHERN WV. 
MESOSCALE BOUNDARIES -- ONE ENTERING WESTERN WV AND NORTHEAST KY
AT THIS TIME -- SHOULD PUSH FARTHER INTO EASTERN KY AND EVENTUALLY
SOUTHWEST VA WITH TIME, INITIATING NEW CONVECTION LATER THIS
MORNING AND THIS AFTERNOON.  PER COORDINATION WITH RNK, WILL
RE-EVALUATE THE RISK IN SOUTHWEST VA LATER TODAY.  HOURLY RAIN
RATES UP TO 2", WITH LOCAL AMOUNTS OF 3-5", COULD LEAD TO
LOCALIZED ISSUES.

ROTH

ATTN...WFO...CLE...ILN...JKL...LMK...PBZ...RLX...RNK...

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

LAT...LON   40338229 39738116 38787967 38527972 37878018
            37428084 37318140 37398294 37768394 38098449
            38738509 39358468 40148329


Last Updated: 942 AM EDT TUE JUN 13 2017