MESOSCALE PRECIPITATION DISCUSSION 0071
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
405 PM EST THU MAR 10 2016
 
AREAS AFFECTED...LOWER MS VALLEY...TN VALLEY...OH VALLEY 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 102104Z - 110104Z
 
SUMMARY...FLOODING CONTINUES ACROSS THE AREA...

DISCUSSION...CONVECTION CONTINUES TO STREAM SOUTH TO NORTH
ALONG/AHEAD OF A BOUNDARY THAT IS ONLY SLOWLY PUSHING EAST.
CONTINUE TO SEE NEAR RECORD BREAKING PRECIPITABLE WATER
ALONG/AHEAD OF THIS BOUNDARY FROM AN IMPRESSIVE ATMOSPHERIC RIVER
WITH CONNECTIONS TO BOTH THE TROPICAL PACIFIC AND THE CARIBBEAN. 

TWO MAIN AREAS OF CONCERN. ONE IS ACROSS THE NORTHERN EDGE OF THE
HEAVIER RAINFALL...FROM NORTHERN MS INTO WESTERN TN AND WESTERN
KY. INSTABILITY IS VERY MARGINAL THIS FAR NORTH...HOWEVER THE
ANOMALOUS MOISTURE AND INCREASING FORCING IS OVERCOMING THIS
RESULTING IN A STEADY MODERATE TO LOCALLY HEAVY RAINFALL. THE
APPROACHING NORTHERN STREAM SHORTWAVE IS ALLOWING THE CONVECTIVE
AREA TO BEGIN PROGRESSING EAST AT A BIT OF A QUICKER RATE...BUT IS
ALSO RESPONSIBLE FOR THE INCREASED SYNOPTIC SUPPORT AND LOW LEVEL
FRONTOGENESIS. THIS AREA OF HIGHER RAINFALL RATES IS HOWEVER
BEGINNING TO MOVE OUTSIDE THE REGION OF SATURATED SOILS...WHICH
SHOULD MAKE THE FLASH FLOOD THREAT MORE MARGINAL AS IT HEADS MORE
TOWARDS CENTRAL TN/KY/AL. THREE HOUR AMOUNTS OF 1-2" WILL PROBABLY
BE COMMON...WITH ISOLATED AMOUNTS POSSIBLY NEAR 2.5". RECENT RUNS
OF THE HRRR MAY BE A BIT TOO FAR SOUTHEAST WITH THE HIGHER QPF IN
THIS REGION...WITH THE 16Z AD 17Z RUNS POSSIBLY A BIT BETTER.

THE OTHER AREA OF CONCERN IS ACROSS EASTERN LA INTO SOUTHERN MS.
WHILE STILL NOT GREAT...THIS AREA IS MORE UNSTABLE THAN FURTHER
NORTH. ALSO BEING FURTHER REMOVED FROM THE NORTHERN STREAM
WAVE...THIS PORTION OF THE FRONT/MOISTURE AXIS SHOULD ONLY
PROGRESS EAST VERY SLOWLY...POTENTIALLY BECOMING NEARLY
STATIONARY. CONTINUED DEEP SOUTHERLY FLOW INTO THIS UNSTABLE AND
MOIST AIRMASS WILL RESULT IN CONTINUED TRAINING CONVECTION OVER
THE NEXT SEVERAL HOURS. INFLOW IS EXPECTED TO WEAKEN THROUGH
AFTERNOON...BUT SHOULD REMAINS STRONG ENOUGH TO MAINTAIN
CONVECTION...POSSIBLY JUST SLIGHTLY LESS ROBUST THAN IS CURRENTLY
BEING SEEN. BUT WITH SOILS SATURATING...THIS ADDITIONAL CONVECTION
WILL CONTINUE TO INCREASE THE FLASH FLOOD RISK OVER THIS AREA.
RECENT RUNS OF THE HRRR AND THE 12Z ARW/NMMB ARE DOING A DECENT
JOB WITH THE HANDLING OF THIS CONVECTIVE AREA. THREE HOUR RAINFALL
TOTALS WILL CONTINUE TO BE AROUND 2".

CHENARD

ATTN...WFO...BMX...HUN...JAN...JKL...LCH...LIX...LMK...MEG...
MOB...OHX...PAH...

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

LAT...LON   37988559 37718470 37148481 36688549 35188648 
            34488705 32308840 29588952 29149074 29339149 
            29589180 30539164 32099140 33779069 35438954 
            36978867 37738707 37648676