MESOSCALE PRECIPITATION DISCUSSION 0099
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
124 AM EDT MON MAY 18 2015
 
AREAS AFFECTED...MS 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 180523Z - 180923Z
 
SUMMARY...CONVECTION CONTINUES TO EXPAND NORTHEASTWARD INTO
NORTHERN MS EARLY MONDAY MORNING.  WITH LOW FFG VALUES AHEAD OF
THIS AREA OF CONVECTION---RUNOFF ISSUES POSSIBLE OVER PORTIONS OF
NORTH CENTRAL MS OVER THE NEXT FEW HOURS.

DISCUSSION...LATEST SATELLITE IMAGERY CONTINUES TO SHOW COOLING
CLOUD TOPS WITH CONVECTION THAT HAS PUSHED OUT OF SOUTHEAST AR AND
INTO NORTHWEST MS.  THIS AREA OF CONVECTION IS FAIRLY
PROGRESSIVE---BUT WITH LOW FFG VALUES OVER PORTIONS OF NORTH
CENTRAL MS---RUNOFF ISSUES ARE POSSIBLE OVER THE NEXT FEW HOURS. 
THE HRR FROM 0300 UTC AND 0400 UTC BOTH APPEAR TO BE TOO SLOW TO
MOVE THIS ACTIVITY NORTHEASTWARD AND BOTH SHOW WEAKENING AFTER
0600-0700 UTC.  WHILE THE WEAKENING IS POSSIBLE---GIVEN THAT THE
HRR IS SLOW WITH THE CURRENT POSITION OF THE CONVECTION--CHANCES
ARE THE ORGANIZED ACTIVITY WILL REACH THE LOWER FFG VALUE AREAS OF
NORTH CENTRAL MS PRIOR TO THIS POSSIBLE WEAKENING.   CONFIDENCE ON
THE WEAKENING HOWEVER IS NOT GREAT AS THE CONVECTION IS IN A
GENERAL FAVORABLE RIGHT ENTRANCE REGION OF THE UPPER JET AND
EMBEDDED IN A VERY MOIST AIRMASS ACROSS THE LOWER MS VALLEY. 
RAINFALL RATES OF 1-2" IN AN HOUR POSSIBLE AS THIS CONVECTION
MOVES NORTHEASTWARD OVER THE NEXT FEW HOURS

ORAVEC

ATTN...WFO...BMX...HUN...JAN...MEG...OHX...

ATTN...RFC...LMRFC...SERFC...

LAT...LON   35798777 35368762 34818748 34668755 34238786 
            33868824 33398898 33258939 33269000 33459033 
            34249072 34929057 35698889