MESOSCALE PRECIPITATION DISCUSSION 0415
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
149 AM EDT FRI JUN 30 2017

AREAS AFFECTED...CENTRAL AND EASTERN KS

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

VALID 300550Z - 301000Z

SUMMARY...SHORT TERM TRAINING OF CONVECTION OVER CENTRAL AND
EASTERN KS COULD RESULT IN A FLASH FLOOD THREAT EARLY THIS MORNING.

DISCUSSION...REGIONAL RADARS SHOWED CONVECTION INTENSIFYING IN A
MOISTURE AXIS AHEAD OF A COLD FRONT STRETCHING ACROSS CENTRAL AND
WESTERN KS EARLY THIS MORNING. THE EXPERIMENTAL GOES-16 CLEAR IR
LOOP SHOWED COLD CLOUD TOPS IN THE MOISTURE AXIS...WITH BUSTS OF
COLDER CONVECTION REACHING -74 CELSIUS.

THE CONVECTION WAS FEEDING ON AN AXIS OF 2000-3000 J/KG OF
MLCAPE...EMBEDDED IN A STRIPE OF 1.75 INCH PRECIPITABLE WATER AIR.
A LONG TERM RADAR LOOP SHOWED A SLOW SOUTHEAST CREEP WITH THE
CONVECTION AS IT CROSSES CENTRAL AND EASTERN KS...WITH KTWX
SHOWING HOURLY RAINFALL RATES BETWEEN 2.50 AND 3.00 INCHES.
HOWEVER...MESONET OBSERVATIONS SUGGEST THAT THE HOURLY RATES ARE
PROBABLY CLOSER TO 1.50 INCHES...AS STEEPENING LAPSE RATES AND DRY
AIR IN THE MID LEVELS SUPPORT HAIL PRODUCTION...WHICH IS INFLATING
HOURLY RAINFALL RATES.

THE SLOW SOUTHEAST MOVEMENT OF THE CONVECTION COULD ALLOW FOR
SHORT TERM TRAINING AND BACKBUILDING...WHICH IN TURN COULD POSE A
FLASH FLOOD RISK...WITH THE GREATEST THREAT ACROSS PORTIONS OF
EASTERN KS. THE LATEST HRRR SUGGESTS LOCAL 2.00 TO 3.00 INCH
RAINFALL AMOUNTS IN THIS AREA... AND THIS WOULD BE CONTINGENT OF
SHORT TERM TRAINING AND/OR BACKBUILDING OCCURRING.

FALLING MID LEVEL HEIGHTS AHEAD OF POSITIVELY TILTED LONG WAVE
TROUGH OVER THE NORTHERN ROCKIES SHOULD ALLOW THE CONVECTION TO
BECOME MORE OUTFLOW DOMINATED AS A COLD POOL BECOMES ESTABLISHED.
THIS IS DEPICTED WELL BY MOST HIGH RESOLUTION MODEL SOLUTIONS
(INCLUDING THE LATEST HRRR)...SO THE FLASH FLOOD THREAT IS
EXPECTED TO DIMINISH AS THE COLD POOL DEVELOPS...AND THE
CONVECTION ACCELERATES SOUTHEASTWARD.

HAYES

ATTN...WFO...DDC...ICT...TOP...

ATTN...RFC...ABRFC...MBRFC...

LAT...LON   39419597 38399531 37949589 37619663 37339790
            37319889 37329905 37599909 37979878 39209661