MESOSCALE PRECIPITATION DISCUSSION 0087
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
957 PM EDT FRI MAY 31 2013
 
AREAS AFFECTED......EASTERN OKLAHOMA ACROSS SOUTHERN
MO...NORTHWEST AR...AND SOUTHERN IL... 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 010157Z - 010757Z
 
SUMMARY...BANDS AND SEGMENTS OF HEAVY SHOWERS AND TRAINING STORMS
WITH A RISK OF FLASH FLOODING WILL MOVE ACROSS EASTERN OKLAHOMA
AND SOUTHERN  MISSOURI INTO SOUTHERN IL.

DISCUSSION...THUNDERSTORMS CONTINUE TO STREAM EAST NORTHEAST
ACROSS SOUTH CENTRAL MO INTO SOUTHERN IL WITH MORE OF AN EAST
SOUTHEAST MOTION IN THE OK PORTION OF THE AREA. 

WINDS FIELDS ARE SUPPORTIVE OF FORWARD MOTION AS NEAR SFC
SOUTHERLY WINDS VEER TO SOUTHWEST AT 850 MB.  ADDITIONAL
DEVELOPMENT IS EXPECTED ALONG OUTFLOW BOUNDARIES TOWARDS THE MOIST
SOUTHERLY INFLOW WITH CORFIDI VECTORS FROM THE 18Z NAM POINTING
FROM NORTHWEST TO SOUTHEAST IN OK AND NORTHWEST AR SUPPORTING
MOTION TOWARDS THE SOUTHEAST.

REDEVELOPMENT SHOULD CONTINUE AS SURFACE LOWER 70S DEWPOINTS AND
PRECIPITABLE WATER VALUES OF  1.5-1.75 INCHES...AND 700-500 MB
LAPSE RATES NEAR 8 DEG C/KM AID STORM DEVELOPMENT.   

THE ECMWF ALSO SHOWS A 300 MB JET MAXIMA AND ASSOCIATED DIVERGENCE
MAXIMA MOVING FROM OK ACROSS MO TO ASSIST IN PRODUCING ASCENT. 
ALSO...THE 12Z ECMWF/18Z NAM SHOW A SEPARATE 700 MB SHORTWAVE
ROTATING TOWARDS THE BASE OF THE TROUGH LATER TONIGHT...AIDING
DEVELOPMENT OF NEW  ACTIVITY OVER EASTERN OK AND SPREADING
DOWNSTREAM FROM THERE INTO NORTHWEST AR. 

THE ACTIVITY OVER THE NEXT SEVERAL HOURS ARE STILL NORTH OF THE
MINIMUM IN THE FLASH FLOOD GUIDANCE VALUES FURTHER SOUTH IN IN
AR...WHERE ACTIVITY SHOULD OCCUR LATER TONIGHT OR EARLY SAT. 1-2
INCHES OF RAIN PER HOUR IS EXPECTED WITH FLOODING POSSIBLE WHERE
LOCAL TRAINING ALLOWS ACTIVITY TO LAST A COUPLE OF HOURS.

PETERSEN


ATTN...WFO...IND...PAH...ILX...LSX...LZK...SGF...TSA...ICT...
OUN...

LAT...LON   35459735 35659674 35829631 35999610 36459550 36779535
            36999512 37229482 37639411 38029317 38509193 38779126
            39159016 39338933 39488878 39488830 39178774 38508764
            38018819 37628876 37298956 37049030 36769097 36539184
            36039326 35539473 35159580 34489711 34509809 35259820
            35459735