MESOSCALE PRECIPITATION DISCUSSION 0365
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
125 AM EDT TUE JUN 21 2016
 
AREAS AFFECTED...NORTHWEST INTO CENTRAL MO 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 210530Z - 210930Z
 
SUMMARY...NEWLY FORMED CONVECTION OVER NORTHWEST MO COULD TRAIN
AND BACKBUILD ACROSS AREAS THAT RECEIVED HEAVY RAINFALL MON
EVENING...RESULTING IN A FLASH FLOOD THREAT THROUGH THE EARLY
MORNING HOURS. 

DISCUSSION...CONVECTION CONTINUES TO FIRE AND TRACK SOUTHEAST
ACROSS PORTIONS OF NORTHWEST MO EARLY THIS MORNING. THE CONVECTION
IS FORMING IN AN AXIS OF 1000-1500 K/JG MLCAPE...AND A POOL OF
NEARLY 2.20 INCH PRECIPITABLE WATER AIR (PER THE 04Z RAP
ANALYSIS...WHICH IS ABOUT TWO STANDARD DEVIATIONS ABOVE THE MEAN).
SYNOPTIC SCALE ASCENT IS PROVIDED VIA A SHORT WAVE MOVING ACROSS
SOUTHWEST IA (PER THE LATEST WATER VAPOR IMAGERY).

THE KEAX RADAR SHOWED HOURLY RAINFALL RATES IN EXCESS OF 2.00
INCHES OVER CLAY COUNTY MO...BUT GIVEN THE AMOUNT OF DRY AIR IN
THE MID LEVELS ON THE LATEST RAP SOUNDINGS...THOSE ESTIMATES COULD
BE HAIL CONTAMINATED. A RECENT MESONET OBSERVATION NEAR ST JOSEPH
MO SHOWED HOURLY VALUES CLOSER TO 1.25 TO 1.50 INCHES. THE HEAVY
RAIN WITH CURRENT CONVECTION IS FALLING OVER AREAS THAT RECEIVED
BETWEEN 2.00 AND 3.00 INCHES OF RAINFALL MON EVENING (PER THE KEAX
DUAL POL STORM TOTAL PRECIPITATION PRODUCT).

THERE IS A DECENT SIGNAL IN THE HIGH RESOLUTION GUIDANCE
(INCLUDING THE LATEST HRRR/EXPERIMENTAL HRRR/RAP) FOR CONVECTION
TO CONTINUE THROUGH 09Z. HOWEVER...THERE IS SOME SPREAD CONCERNING
RAINFALL AMOUNTS DURING THAT TIME. GIVEN THE INSTABILITY AND
MOISTURE IN PLACE...THE 04Z HRRR AMOUNTS OF LOCAL 2 INCH AMOUNTS
SEEMS REASONABLE. THESE RAINFALL AMOUNTS COULD RESULT IN A FLASH
FLOOD THREAT... ESPECIALLY WHERE BACKBUILDING OR TRAINING
OCCURS...AS THE 04Z RAP SHOWED CORFIDI VECTORS NEAR THE CONVECTION
DROPPING TO UNDER 10 KNOTS FOR A TIME BETWEEN 05 UTC AND 08 UTC. 

HAYES

ATTN...WFO...EAX...LSX...SGF...

ATTN...RFC...MBRFC...NCRFC...

LAT...LON   40439491 40329384 39509237 39189171 38749144 
            38389170 38179200 38149256 38279347 38529390 
            39089447 39589498 39589498 39859504