MESOSCALE PRECIPITATION DISCUSSION 0648
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1239 AM EDT WED SEP 07 2016
 
AREAS AFFECTED...NORTHERN KS...SOUTHEAST NEB 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 070435Z - 070845Z
 
SUMMARY...STRONG AND SLOW-MOVING THUNDERSTORMS WILL CONTINUE TO
PRODUCE HEAVY RAINS AND CONCERNS FOR FLASH FLOODING OVER THE NEXT
SEVERAL HOURS. 

DISCUSSION...LOCALIZED STRONG CONVECTION FOCUSED OVER ESPECIALLY
GRAHAM COUNTY AND ADJACENT PORTIONS OF ROOKS AND SHERIDAN COUNTIES
OVER THE LAST COUPLE OF HOURS CONTINUES TO MOVE VERY SLOWLY...BUT
HAS BEEN EXPANDING IN COVERAGE AND ORGANIZATION ESPECIALLY OVER
THE LAST HOUR.

THE ACTIVITY WHICH WAS INITIATED BY PROXIMITY OF A STALLING COLD
FRONT INTERACTING WITH A POOL OF MODERATE INSTABILITY...AND A DEEP
POOL OF MOISTURE...IS EXPECTED TO GAIN SOME ADDITIONAL
ORGANIZATION OVER THE NEXT FEW HOURS AS A MID LEVEL SHORTWAVE
EJECTING EAST ACROSS THE CO HIGH PLAINS INTERACTS WITH THE FRONT
AND AN INCREASINGLY STRONG SOUTHWEST LOW LEVEL JET WHICH IS
ALREADY ON THE ORDER OF 40 TO 45 KTS ACROSS WEST-CENTRAL KS AHEAD
OF THE FRONT AND CURRENT MCS.

PWATS OVER THE REGION ARE CLOSE TO 1.75 INCHES BASED ON THE LATEST
BLENDED-TPW PRODUCT AND PER RAP ANALYSIS. THIS IS FOSTERING VERY
HEAVY RAINFALL RATES...AND DUAL-POL RADAR ESTIMATES HAVE BEEN
REPEATEDLY ON THE ORDER OF 1.75 TO 2 INCHES/HR IN AND AROUND THE
AFOREMENTIONED COUNTIES WHERE STORM TOTALS ARE APPROACHING 5
INCHES LOCALLY.

CONVECTION IS LIKELY TO CONTINUE TO SLOWLY EXPAND NORTHEAST UP
ALONG THE NOW STATIONARY BOUNDARY AS THE SHORTWAVE EJECTS
EAST-NORTHEAST OVERNIGHT...AND WITH THE LOW LEVEL JET PERHAPS
INCREASING A TAD FURTHER AND COUPLING WITH SOME MODEST
RIGHT-ENTRANCE REGION JET FORCING ALOFT...CONVECTION IS EXPECTED
TO ORGANIZE A TAD FURTHER WITH LOCALLY VERY HEAVY RAINFALL AMOUNTS
EXPECTED. THIS MEANS HEAVY CONVECTIVE RAINS APPROACHING THE KS/NEB
BORDER AND GRADUALLY GETTING INTO PARTS OF SOUTHEAST NEB.

ADDITIONAL RAINFALL AMOUNTS OF AS MUCH AS 3 TO 5 INCHES ARE
EXPECTED...WITH LOCALLY HEAVIER STORM TOTALS POSSIBLE WHERE SOME
TRAINING OCCURS. THIS WILL FOSTER ADDITIONAL FLASH FLOODING
CONCERNS THROUGH THE OVERNIGHT HOURS.

ORRISON

ATTN...WFO...DDC...GID...GLD...ICT...OAX...TOP...

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

LAT...LON   40999671 40889597 40229566 39579609 39239662 
            38839762 38609885 38579962 38749990 39060016 
            39340014 39739977 40459867 40959729 
A