MESOSCALE PRECIPITATION DISCUSSION 0176
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1242 AM EDT MON MAY 01 2017

AREAS AFFECTED...SOUTHEAST MS...SOUTHWEST AL...FAR WESTERN FL
PANHANDLE

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

VALID 010441Z - 010900Z

SUMMARY...SOME ADDITIONAL SHOWERS AND THUNDERSTORMS WITH SOME
LOCALIZED TRAINING OF CELLS MAY CONTINUE FOR A FEW MORE HOURS.
FLASH FLOODING REMAINS POSSIBLE.

DISCUSSION...A SOMEWHAT FOCUSED AREA OF THUNDERSTORMS REMAINS
INTACT OVER AREAS OF SOUTHEAST MS INVOLVING CLARKE...WAYNE AND
PERRY COUNTIES AS A SURFACE COLD FRONT CONTINUES TO GRADUALLY
ADVANCE EAST AND INTERACTS WITH A NOTABLE INSTABILITY AXIS POOLED
UP ALONG THE BOUNDARY. EXPERIMENTAL GOES-16 10.3 MICRON/IR IMAGERY
HAS SHOWN A GENERAL COOLING OF CLOUD TOPS OVER THIS AREA WITH A
COUPLE OF OVERSHOOTING TOPS. MEANWHILE...THERE HAS BEEN SOME
CONVECTIVE REDEVELOPMENT NOTED OVER AREAS OF FAR SOUTHERN
AL..ESPECIALLY IN AND AROUND MOBILE...IN THE WAKE OF THE EARLIER
BAND OF CONVECTION THAT CROSSED THE REGION.

THE AFOREMENTIONED COLD FRONT HAS BEEN TENDING TO SLOW DOWN
SOMEWHAT OVER THE LAST FEW HOURS...BUT IS EXPECTED TO MAKE MORE
PROGRESS IN ADVANCING EAST OVERNIGHT AS THE DEEP LAYER
TROUGH/CLOSED LOW EXITING THE CENTRAL PLAINS LIFTS TO THE
NORTHEAST. HOWEVER...THE LOW LEVEL FLOW ACROSS THE CENTRAL GULF
COAST REGION REMAINS QUITE CONFLUENT WITH A RELATIVELY DIFFLUENT
UPPER AIR FLOW PATTERN. A 40 TO 45 KT LOW LEVEL JET FROM THE SOUTH
IS ALLOWING A NOSE OF MLCAPE VALUES REACHING 1000 TO 1500 J/KG AND
PWATS OF OVER 1.75 INCHES TO FOCUS OVER THE CENTRAL GULF COAST
REGION AND THIS WILL STILL SUPPORT HEAVY RAINFALL RATES OF OVER 2
INCHES/HR OVER THE NEXT FEW HOURS AS CONVECTION IS LIKELY TO
PERSIST UNTIL THE COLD FRONT PASSES.

SOME ADDITIONAL FLASH FLOODING CONCERNS ARE POSSIBLE GIVEN THE
RAINFALL RATES...AND SOME LOCALIZED TRAINING CONVECTIVE CELL
ACTIVITY. AN ADDITIONAL 3 TO 4 INCHES OF RAIN IS POSSIBLE
LOCALLY...BUT CONDITIONS ARE EXPECTED TO IMPROVE TOWARD DAWN AS
THE COLD SLOWLY CROSSES THE REGION.

ORRISON

ATTN...WFO...BMX...JAN...LIX...MOB...

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

LAT...LON   32948787 32768730 32038738 31218685 30348715
            30098761 30208838 30598860 31098892 31688891
            32198868 32738838