MESOSCALE PRECIPITATION DISCUSSION 0301
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
212 PM EDT FRI JUN 03 2016
 
AREAS AFFECTED...NORTHWEST MS...FAR EASTERN AR...WESTERN TN...FAR
SOUTHEAST MO 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 031805Z - 032230Z
 
SUMMARY...EXPANDING COVERAGE OF SLOW-MOVING SHOWERS AND
THUNDERSTORMS SHOULD RESULT IN AT LEAST SOME ISOLATED FLASH FLOOD
CONCERNS THIS AFTERNOON.

DISCUSSION...CONVECTION CONTINUES TO GRADUALLY EXPAND IN COVERAGE
ALONG AND ADJACENT THE MS RIVER INCLUDING AREAS OF WESTERN
MS...EASTERN AR AND WESTERN TN. THE ACTIVITY IS FOCUSING WITHIN A
GRADUALLY SHARPENING INSTABILITY GRADIENT AND WITHIN A BROADLY
DIFFLUENT FLOW REGIME ALOFT. THE LOW LEVEL FLOW IS ALSO SOMEWHAT
CONFLUENT ALONG AND JUST EAST OF THE MS RIVER WHICH IS FAVORING A
MODEST DEGREE OF LOW LEVEL FORCING. PROXIMITY OF A FRONT OVER THE
LOWER OH VALLEY AND DOWN ACROSS SOUTHEAST MO AND NORTHWEST AR IS
ALSO A NOTED FORCING MECHANISM.

THE PWATS ARE QUITE HIGH ACROSS THE REGION AS A RESULT OF THE
DEEPER LAYER SOUTHERLY FLOW AROUND THE EASTERN FLANK OF THE DEEP
CLOSED LOW OVER CENTRAL TX. THE BLENDED-TPW IMAGERY INDICATES
PWATS CLOSE TO 1.75 INCHES ACROSS THE REGION AND THIS WILL ENHANCE
THE RAINFALL RATES THROUGH THE AFTERNOON.

THE OVERALL CELL PROPAGATION IS VERY WEAK AND GENERALLY TO THE
NORTH AND NORTHEAST...BUT STORM MOTION VECTORS ARE UNDER 10 KTS.
CONSEQUENTLY...RAINFALL TOTALS ARE EXPECTED TO BE RATHER HEAVY
GIVEN THE INTENSE RATES AND DURATION. 

OVER THE NEXT FEW HOURS WITH ADDITIONAL DIURNAL HEATING...SURFACE
BASED INSTABILITY WILL INCREASE FURTHER AND SO THE COVERAGE OF
CELLS SHOULD INCREASE A BIT MORE. EXPECTING ALSO A FEW
CELL-MERGERS THIS AFTERNOON TOO...AND WITH THE ENVIRONMENTAL
CONDITIONS...EXPECT SOME RAINFALL TOTALS OF 3 TO 4 INCHES AND
POSSIBLY HIGHER. THUS SOME FLASH FLOODING WILL BE POSSIBLE.

ORRISON

ATTN...WFO...JAN...LZK...MEG...PAH...SGF...

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

LAT...LON   36989108 36758960 35888913 34508932 33238999 
            33009091 33299128 34769085 35739100 36499132