MESOSCALE PRECIPITATION DISCUSSION 0617
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
147 AM EDT MON AUG 29 2016
 
AREAS AFFECTED...FAR SOUTHERN NEB....FAR NORTHERN KS 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 290545Z - 290800Z
 
SUMMARY...CLUSTER OF VERY SLOW MOVING THUNDERSTORMS WILL CONTINUE
TO FOCUS HEAVY RAINFALL OVER THE NEXT COUPLE OF HOURS.

DISCUSSION...VERY COLD TOPPED CONVECTION WITH EMBEDDED
OVERSHOOTING TOPS HAS BEEN PERSISTING OVER FAR SOUTHERN NEB AND
NEAR THE BORDER WITH KS OVER THE LAST COUPLE OF HOURS. THE
CONVECTION IS EMBEDDED WITHIN A RATHER DIVERGENT FLOW PATTERN
ALOFT WELL NORTHEAST OF A MID LEVEL LOW CENTER OVER NORTHERN NM.

THE CONVECTION HAS BEEN STRONG ENOUGH THAT IT HAS PUT DOWN AN
OUTFLOW BOUNDARY WHICH CAN BE SEEN IN THE HASTINGS NE DUAL-POL
ADVANCING OFF TO THE SOUTHWEST. LOW LEVEL SOUTHERLY FLOW WILL BE
OVERRUNNING THIS BOUNDARY AND ASSOCIATED COLD POOL...AND WILL
LIKELY HELP TO REGENERATE CONVECTION OVER AT LEAST THE NEXT COUPLE
OF HOURS.

PWATS IN VICINITY OF THE CONVECTION ARE ON THE ORDER OF 1.5 TO 1.7
INCHES WHICH WILL FACILITATE RAINFALL RATES IN EXCESS OF 2
INCHES/HR. THE OCCASIONAL OVERSHOOTING TOPS WILL ONLY ENHANCE THE
RATES FURTHER....AND GIVEN THE VERY SLOW MOVEMENT OF THE OVERALL
CONVECTIVE CLUSTER...VERY HEAVY RAINFALL AMOUNTS ARE EXPECTED.
ALREADY THERE IS AS MUCH AS 3 TO 5 INCHES OF RAIN LOCALLY VIA
DUAL-POL ESTIMATES.

THE LATEST HRRR GUIDANCE SUGGESTS ANOTHER 2 TO 4 INCHES
LOCALLY...AND THIS WILL SUPPORT SOME RUNOFF/FLASH FLOOD CONCERNS
FOR ANOTHER 2 TO 3 HOURS BEFORE THE CONVECTION THEN WEAKENS. WILL
CONTINUE TO MONITOR.

ORRISON

ATTN...WFO...GID...TOP...

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

LAT...LON   40809833 40679751 39959759 39369853 39849938