Storms continue to train over the same areas in Louisiana and South Mississippi and the WPC is started to get concerned about flash flooding across parts of the Pine Belt and the Parishes of Louisiana.
MESOSCALE PRECIPITATION DISCUSSION 0594
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
122 AM EDT SUN JUL 14 2019AREAS AFFECTED…PORTIONS OF EASTERN LA AND CENTRAL/SOUTHERN MS CONCERNING…HEAVY RAINFALL…FLASH FLOODING POSSIBLE
VALID 140520Z – 140930ZSUMMARY…A NARROW TRAINING BAND OF HEAVY SHOWERS WILL BE TRAINING ACROSS THE SAME AREA INVOLVING PORTIONS OF CENTRAL/SOUTHERN MS AND POSSIBLE FAR EASTERN LA OVER THE NEXT FEW HOURS. VERY HEAVY RAINFALL RATES OF NEAR 2 INCHES/HR WILL FOSTER SOME CONCERNS FOR FLASH FLOODING.
DISCUSSION…THE LATEST RADAR IMAGERY SHOWS A RATHER NARROW AXIS OF SHOWERS TRAINING FROM SOUTH TO NORTH ACROSS CENTRAL/SOUTHERN MS. THE ACTIVITY IS WARM-TOPPED IN NATURE AND IS FOCUSING WITHIN MODESTLY CONFLUENT LOW-LEVEL SOUTHERLY FLOW AROUND THE FAR EASTERN SEMICIRCLE OF T.S. BARRY’S CIRCULATION. THE CONVECTION IS ALSO ALIGNED WITH A RATHER STRONG INSTABILITY GRADIENT.
GIVEN THE WARM-TOPPED NATURE OF THE CONVECTION, AND PRESENCE OF A DEEP TROPICAL ENVIRONMENT AS SEEN IN THE LATEST CIRA-LPW IMAGERY, WARM RAIN PROCESSES WILL DOMINATE AND THIS WILL YIELD ENHANCED RAINFALL RATES. EXPECT RAINFALL RATES OF AS MUCH AS 2 INCHES/HR.
THE LATEST HRRR GUIDANCE SUPPORTS AS MUCH AS 2 TO 4 INCHES OF RAIN GOING THROUGH 09Z, AND THE POTENTIAL WILL EXIST FOR ADDITIONAL CONVECTIVE BANDS TO DEVELOP AND TRAINING NORTHWARD OVER THE SAME AREA BEYOND THIS TIME FRAME GIVEN THE EXPECTED PERSISTENCE OF RELATIVELY CONFLUENT LOW-LEVEL FLOW AND THE PROXIMITY OF THE AFOREMENTIONED INSTABILITY GRADIENT.
GIVEN THE SHORT-TERM RAINFALL RATES OVER THE NEXT FEW HOURS, SOME FLASH FLOODING WILL BE POSSIBLE.
