MESOSCALE PRECIPITATION DISCUSSION 0171
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
601 PM EDT THU JUN 04 2015
 
AREAS AFFECTED...NE/KS BORDER TO ADJACENT MO/IA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 042200Z - 050400Z
 
SUMMARY...BURSTS OF VERTICAL MOTION NEAR MULTIPLE LOW LEVEL
BOUNDARIES SUPPORTS LINES AND CLUSTERS OF SHOWERS/STORMS, WHICH
WILL LIKELY LEAD TO FLOODING GIVEN OVERLAP WITH EARLIER RAINFALL
AND LOWERED AMOUNTS NEEDED TO PRODUCE FLOODING.

DISCUSSION...A NEW BAND OF HEAVY SHOWERS AND STORMS HAS FORMED
WITHIN A REGION OF LOW-MID LEVEL MOISTURE ADVECTION AND BOUNDARY
LAYER MOISTURE CONVERGENCE.  THIS IS WITHIN A TIGHT TEMPERATURE
GRADIENT AND MOST UNSTABLE CAPES TO NEAR 2000 J/KG. 
SURFACE COOLING FROM EARLIER ACTIVITY HAS LEFT AN EFFECTIVE FRONT
ACROSS NORTHERN KS WITH THE FORECAST SOUNDINGS SHOWING LOW-MID
LEVEL WARM ADVECTION OVER THE LOW LEVEL EFFECTIVE FRONT
PRECIPITABLE WATER VALUES REMAIN NEAR 1.75".

CONTINUING 850-700 MB THETA-E ADVECTION INTO THE REGION COMBINES
WITH 300 MB DIVERGENCE MAXIMA TO SUPPORT MORE SHOWERS AND STORMS
DEVELOPING. CORFIDI VECTORS SHOW AN EAST-SOUTHEAST PROPAGATION
LIKELY, WHICH WOULD LEAD TO CELLS DEVELOPING OR MOVING INTO THE
REGION NEAR THE EASTERN NEBRASKA/KANSAS BORDER AND POSSIBLY INTO
ADJACENT MO. 

CELL TRAINING IS POSSIBLE, LEADING TO A HEAVY RAINFALL THREAT IN A
REGION HIT EARLIER TODAY.  THE 16-21Z HIGH RESOLUTION RAPID
REFRESH RUNS TARGET THE AREA NEAR THE EASTERN NEBRASKA BORDER. 
BANDS OF 2-3" ARE EXPECTED NEAR THE KS/NE BORDER.  WITH 3 HOUR
FLASH FLOOD GUIDANCE UNDER 1.5 INCHES, THE EXPECTED RAIN SHOULD
LEAD TO FLOODING WHERE CELLS TRAIN.  

PETERSEN

ATTN...WFO...EAX...GID...OAX...TOP...

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

LAT...LON   41229873 40779601 40499452 39769429 39119535 
            39129710 39609846 40449923