MESOSCALE PRECIPITATION DISCUSSION 0197...CORRECTION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
904 AM EDT MON AUG 05 2013
 
AREAS AFFECTED...SOUTHERN MO AND NORTHEAST AR 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 051303Z - 051603Z
 
SUMMARY...THE CLOUD TOPS OF TRAINING CONVECTION ACROSS
SOUTH-CENTRAL MO HAS SHOWN SOME RECENT COOLING ON SATELLITE
IMAGERY, AND LOW-LEVEL INFLOW HAS SHOWN A RECENT UPTICK IN
INTENSITY.  FLASH FLOODING WILL BE POSSIBLE IN THIS REGION OVER
THE NEXT FEW HOURS.

DISCUSSION...A CONVECTIVE MASS ACROSS SOUTH-CENTRAL MO HAS BEEN
RELATIVELY STEADY STATE OVER THE PAST COUPLE HOURS, WITH SOME
BACKBUILDING ALONG ITS NORTHWEST FRINGE CONTINUING.  DIVERGENCE IS
BEING CAUSED BY THE SOUTHERN FRINGE OF THE WESTERLIES, WITH NO
STRONG SHORTWAVE ALOFT INVOLVED.  LOW-LEVEL INFLOW AT THE 850 HPA
LEVEL HAS RECENTLY INCREASED TO 40-45 KNOTS, IMPORTING MUCAPE
VALUES IN EXCESS OF 2000 J/KG -- WHICH ARE NOT EXPECTED TO
DECREASE -- OVER A SURFACE FRONT WITH CIN FORCING CONVECTION TO BE
ELEVATED NORTHEAST OF A STATIONARY FRONT, WHICH REMAINS WELL TO
THE SOUTHWEST ACROSS OK.  THESE VALUES ARE ENOUGH TO MAINTAIN
ONGOING ORGANIZED CONVECTION.  

RAINFALL RATES OF UP TO 1-1.5 INCHES PER HOUR HAVE BEEN SEEN IN
THE STRONGER ACTIVITY PER NSSL QPE ESTIMATES, WHICH EXCEED HOURLY
FLASH FLOOD GUIDANCE VALUES -- FFGS.  RECENT CLOUD TOP COOLING
SUGGESTS THAT SLIGHTLY HIGHER RAINFALL RATES, ON THE ORDER OF
1.5-2 INCHES PER HOUR, ARE POSSIBLE.  AS THERE IS CELL TRAINING,
THREE HOURLY FFGS ARE EXPECTED TO BE EXCEEDED ON A LOCAL BASIS,
THOUGH THE ACTIVITY SHOULD SHIFT SOMEWHAT SOUTH AND EASTWARD
THROUGH THE REMAINDER OF THE MORNING AS THE BEST 850 HPA INFLOW
VEERS TOWARDS A MORE WEST-EAST AXIS/ORIENTATION.  THE GUIDANCE IS
SHOWING MIXED SIGNALS IN REGARDS TO ITS CONTINUED EXISTENCE, WITH
THE 06Z HRRR SHOWING AN IMMEDIATE COLLAPSE TO THIS ACTIVITY, WHILE
THE 11Z RAP RUN RECENTLY REVERSED ITS FORECAST OF DECREASING
LOW-LEVEL INFLOW, AND NOW MAINTAINS 35+ KNOTS OF LOW-LEVEL INFLOW
THROUGH 17Z, WHICH SUPPORTS RECENT VAD WIND PROFILES ACROSS KS AND
MO.  CLIMATOLOGY FOR THE PRECIPITABLE WATER VALUES INVOLVED --
2.25 INCHES WHICH IS ABOVE THE 90TH PERCENTILE FOR EARLY AUGUST --
SUGGEST ACTIVITY SHOULD KEEP GOING TO 15Z.  AS A COMPROMISE, WILL
ALLOW THE MPD TO BE VALID UNTIL 16Z FOR POSSIBLE REGIONAL FLASH
FLOODING.

ROTH

ATTN...WFO...PAH...MEG...LSX...LZK...SGF...

ATTN...RFC...ABRFC...LMRFC...MBRFC...NCRFC...

LAT...LON   35449040 35219163 35679250 36749309 37759315 38479258
            38559185 38309094 37368997 36038987 35449040