MESOSCALE PRECIPITATION DISCUSSION 0460
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
341 AM EDT WED JUL 13 2016
 
AREAS AFFECTED...NORTHEAST CO INTO NORTHWEST KS 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 130740Z - 131240Z
 
SUMMARY...TRAINING ALONG AN INSTABILITY AXIS ACROSS NORTHEAST CO
INTO NORTHWEST KS SHOULD RESULT IN A CONTINUING FLASH FLOOD THREAT
THROUGH THE EARLY MORNING HOURS.

DISCUSSION...KFTG RADAR CONTINUES TO SHOW CONVECTION
DEVELOPING/MOVING ALONG AN INSTABILITY AXIS ROUGHLY ORIENTED ALONG
40N. A 25 KNOT LOW LEVEL SOUTHEAST INFLOW (AS DEPICTED BY THE KGLD
VWP) IS TRANSPORTING 1.00 TO 1.25 INCH PRECIPITABLE WATER INTO THE
CONVECTION. KFTG AND KGLD RADARS HAVE INDICATED HOURLY RAINFALL
RATES AS HIGH AS 2.00 INCHES... AND WHILE THERE COULD BE SOME HAIL
CONTAMINATION...THE KDP PRODUCTS SHOWED STRONG HEAVY RAIN CORES
MOVING INTO NORTHWEST KS. 

A SHORT WAVE OVER NORTHEAST CO WILL TRACK EAST DURING THE PREDAWN
HOURS...ALLOWING THE CONVECTIVE ORGANIZATION TO CONTINUE. AS THE
SHORT WAVE PASSES...MID LEVEL WINDS WILL SHIFT TO THE NORTHWEST.
THIS SHOULD ALLOW THE CONVECTION TO BEGIN DROPPING SOUTHEAST WITH
TIME...AS CORFIDI VECTORS SUGGEST JUST SUCH A SHIFT. THIS IS
EXPECTED TO BRING THE HEAVY RAIN CORES OVER MORE OF NORTHWEST KS
BEFORE 10Z.

AFTER THAT TIME...CAPPING SHOULD BEGIN TO ELEVATE THE CONVECTION
ACROSS NORTHEAST CO...AS THE LOW LEVEL INFLOW WEAKENS. THE FLASH
FLOOD THREAT THERE SHOULD BEGIN TO DROP OFF. JUST HOW FAR SOUTH
INTO NORTHWEST KS THE FLASH FLOOD THREAT GETS IS PROBLEMATIC, RAP
MODEL SOUNDINGS SHOWED FAIRLY STRONG CAPPING AT 700 MB SOUTH OF
KGLD (ON THE ORDER OF 5 DEGREES CELSIUS)...WHICH SHOULD PRODUCE A
SOUTHERN EDGE TO THE STRONGER CONVECTION.

THE 06Z HRRR INDICATES THAT THE HEAVIEST RAIN CORES REMAIN IN
NORTHWEST KS THROUGH 10Z...THEN DROP SOUTHEAST INTO THE CAPPED
AREA. BY CONTRAST...THE 00Z WRF ARW DROPS 2-4 INCH RAINFALL
AMOUNTS SOUTH OF KGLD INTO WESTERN AND PORTIONS OF CENTRAL KS.
CONSIDERING THE STRENGTH OF THE CAPPING EXPECTED TO BE IN
PLACE...THIS IS PROBABLY TOO FAR SOUTH,

LOCAL 2-3 INCH RAINFALL AMOUNTS ARE POSSIBLE WHERE TRAINING
OCCURS... ESPECIALLY OVER NORTHWEST KS...AND THESE AMOUNTS AGREE
WITH THE LATEST HRRR. ONE AND THREE HOUR FLASH FLOOD GUIDANCE
BECOMES HIGHER SOUTH OF KGLD...SO FLASH FLOODING IS CONSIDERED
POSSIBLE THROUGH THE EARLY MORNING HOURS THAT FAR SOUTH.

HAYES

ATTN...WFO...DDC...GID...GLD...

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

LAT...LON   40260215 39980049 39900012 39579947 38959930 
            38759967 38800015 39460235 39630260 39700264 
            39700265 40000269 40190250